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Aim: To compare implant survival and complication rates between shorter and standard‐length implants with sinus augmentation and restored with single crowns, at 10 years of loading. Materials and Methods: One‐hundred and one patients (137 implants) with a ridge height of 5–7 mm in the posterior maxilla were randomly assigned to two treatment modalities: shorter implants (6 mm) (group short [GS]) or standard‐length implants (11–15 mm) with sinus grafting (group graft [GG]). Following the insertion of final restorations, patients were regularly recalled for up to 10 years. Assessed outcomes encompassed implant survival, marginal bone levels (MBLs), biological and technical parameters and patient‐reported outcome measures (OHIP‐49 = Oral Health Impact Profile). Non‐parametric statistical analysis was used to analyse the data. Results: For the 5‐ to 10‐year follow‐up period, 77 patients with 105 implants (GS: 36 patients/48 implants; GG: 41/57) were available for re‐examination (drop‐out rate 21%). Implant survival rates at the patient level were 96.0% (GS; 2 failures) and 100% (GG) (inter‐group p =.24). Median MBLs amounted to 0.00 mm (min 0.00; max 3.25; GS) and 0.00 mm (min 0.00; max 4.55; GG) (inter‐group p =.73). Technical complications predominantly occurred within the first 5 years (inter‐group p >.05). Peri‐implantitis rates were 4.2% (GS) and 13.3% (GG) (intergroup p =.37). Median OHIP‐49 scores were 7.00 (0.00; 39.00; GS) and 9.00 (0.00; 196; GG) (inter‐group p =.61) at 10 years. Conclusions: Based on similar 10‐year implant survival rates, reduced patient morbidity and lower costs, the use of shorter dental implants might well serve as an alternative treatment concept to longer implants placed in conjunction with sinus grafting for patients with a limited ridge height in the posterior maxilla. Study register: https://clinicaltrials.gov/ct2/show/NCT01030523. [ABSTRACT FROM AUTHOR]

Statement of Problem: Emerging evidence indicates that the emergence profile and subsequent restorative angle play a crucial role in clinical outcomes and can potentially affect the development and progression of peri‐implant diseases. However, the traditional evaluation of the emergence profile and angle has been limited to mesial and distal sites using periapical x‐rays, without considering the buccal sites. Purpose: To describe a novel 3D method to estimate the emergence profile and restorative angles around single implant‐supported crowns including buccal sites. Materials and Methods: A total of 30 implant‐supported crowns (11 molars, 8 premolars, 8 central incisors and 1 canine) were extra‐orally scanned using an intraoral scanner and the STL files produced were imported into a 3D software. The crown/abutment interface of each crown was delineated, and apico‐coronal lines were automatically drawn following the shape of the crown. Three reference points were defined on the apico‐coronal lines at the transition edge of the biological (BC) and the esthetic zone (EC) and the resulting angles were then calculated. The reliability of the measurements (2D and 3D) were assessed using the intraclass correlation coefficient (ICC). Results: In anterior restorations, the mean angle of the esthetic zone amounted to 162 ± 14° at mesial sites, to 140 ± 10° at buccal sites and to 163 ± 11° at distal sites. The corresponding angles at the biological zones, amounted to 155 ± 13° at mesial sites, 139 ± 15° at buccal sites and 157 ± 5° at distal sites. In posterior restorations, the mean angle of the esthetic zone amounted to 162 ± 12° at mesial sites, to 157 ± 13 at buccal sites and to 162 ± 11 at distal sites. The corresponding angles at the biological zone, amounted to 158 ± 8 at mesial sites, 150 ± 15° at buccal sites and 156 ± 10 at distal sites. The ICC for all measurements ranged between 0.77 and 0.99 indicating a good intra‐examiner reliability. Conclusion: Within the limitations of the present study, the 3D analysis seems to be a reliable and applicable method for the quantitative evaluation of the emergence profile in daily practice. Future randomized clinical trials are needed to assess whether a 3D analysis with the ensuing the emergence profile serves as a predictor for clinical outcomes. Clinical Significance: The development and implementation of a 3D workflow will provide technicians and dentists with the ability to assess the restorative angle of implant‐supported restorations during the provisional phase and the final restoration. This approach may help achieve an aesthetically pleasing restoration while minimizing potential clinical complications. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare patient‐reported outcome measures (PROMs) of soft tissue substitutes versus autogenous grafts for soft tissue augmentation procedures at implant sites. Comprehensive and systematic literature searches were performed until December 2021. A focused question was formulated based on the Population, Intervention, Comparison and Outcome criteria (PICO): In patients with dental implants undergoing soft tissue augmentation (P), do soft tissue substitutes (I) compared to autogenous soft tissue graft (SCTG [subepithelial connective tissue graft]) (C) limit the post‐operative morbidity and other patient reported‐outcomes measures (O). Randomized controlled clinical trials, prospective‐, retrospective‐ and case‐series studies were included. Meta‐analyses were performed whenever possible and the results were expressed as weighted mean differences (WMD). A total of 29 clinical studies were included. For mucosal thickness gain, soft tissue substitutes significantly reduced the pain perception compared to SCTG (n = 4; WMD = 14.91 Visual Analog Scale [VAS] units; 95% confidence interval [CI] 6.42‐23.40; P <.0006) based on a 0‐100 VAS scale. Based on a 0‐10 VAS scale, a borderline significance of pain reduction was found when soft tissue substitutes were applied (n = 4; WMD = 1.62 VAS units; 95% CI 0.01‐3.23; P =.05). For keratinized tissue gain, soft tissue substitutes significantly reduced the pain perception after keratinized tissue augmentation compared to SCTG based on a 0‐100 VAS scale (n = 2; WMD = 21.43 VAS units; 95% CI 12.58‐30.28; P <.0001). Based on the 0‐10 VAS scale, soft tissue substitutes significantly reduced the pain as compared to SCTG (n = 4; WMD = 1.65 VAS units; 95% CI 0.66‐2.64; P =.001). Regarding pain medication, soft tissue substitutes required less painkillers (n = 6; WMD = 1.56 tablets; 95% CI 1.22‐1.91; P <.00001) after soft tissue augmentation. The surgery time was significantly reduced when soft tissue substitutes were used (n = 5; WMD = 10.9 minutes; 95% CI 4.60‐17.19; P <.00001). There were no significant differences in satisfaction, aesthetics, and quality of life (OHIP‐14) between soft tissue substitutes and autogenous grafts following soft tissue augmentation at implants sites. Soft tissue substitutes, compared to autogenous grafts, significantly improve PROMs following soft tissue augmentation at implant sites. Soft tissue substitutes can reduce pain perception, amounts of painkillers and surgery time while achieving similar levels of patient´s satisfaction as autogenous grafts without impairing the clinical outcomes. The current evidence indicates that they constitute a valid and reliable alternative to minimize the invasiveness in soft tissue augmentation procedures at implant sites. [ABSTRACT FROM AUTHOR]

The management and prevention of soft tissue complications is of key importance in modern implant dentistry and influences biologic and esthetic outcomes. The assessment of the soft tissue conditions from a quantitative and qualitative perspective should, therefore, be part of the overall treatment plan. Such an assessment dictates a potential indication as well as an ideal time point for additional soft tissue management. A proper risk assessment and management of the soft tissues at the planned implant site are of key importance prior to any implant-related surgery. Cases with peri-implant soft tissue complications generally involve: (a) a lack of attached and keratinized mucosa; (b) insufficient volume; (c) development of mucosal dehiscences; or (d) a combination of (a), (b), and (c). In case of soft tissue deficiencies, these should be addressed as early as possible to increase the predictability of the surgical interventions. This article reviews the main causes for peri-implant soft tissue complications and presents different therapeutic options for the management of various clinical scenarios. [ABSTRACT FROM AUTHOR]

Aim: To test whether or not the use of a short implant with a cantilever results in similar clinical and radiographic outcomes compared to two adjacent short implants with single tooth reconstructions. Materials and methods: Thirty‐six patients with two adjacent missing teeth in the posterior region were randomly assigned to receive either a single 6‐mm implant with a cantilever (ONE‐C) or two 6‐mm implants (TWO). Fixed reconstructions were inserted 3–6 months after implant placement and patients were re‐examined up to 5 years (FU‐5). Results: A total of 26 patients were available for re‐examination at FU‐5. The survival rate amounted to 84.2% in ONE‐C and to 80.4% in TWO (inter‐group: p =.894). Technical complication rates amounted to 64.2% (ONE‐C) and to 54.4% (TWO) (inter‐group: p = 1.000). From baseline to FU‐5, the median changes of the marginal bone levels were 0.13 mm in ONE‐C and 0.05 mm in TWO (inter‐group: p =.775). Probing depth, bleeding on probing, and plaque control record values showed no significant differences between the two treatment modalities (p >.05). Conclusions: Short implants with a cantilever render similar clinical and radiographic outcomes compared to two adjacent short implants at 5 years, however, they tend to fail at earlier time points suggesting an overload of the implants. Considering the modest survival rates, the clinical indication of either treatment option needs to be carefully evaluated. ClinicalTrials.gov (NCT01649531). [ABSTRACT FROM AUTHOR]

Objectives: The task of working Group 2 at the 6th Consensus Meeting of the European Association for Osseointegration was to comprehensively assess the effects of soft tissue augmentation procedures at dental implant sites on clinical, radiographic and patient‐reported outcome measures (PROMs) including an overview on available outcome measures and methods of assessment. Materials and methods: Three systematic reviews and one critical review were performed in advance on (i) the effects of soft tissue augmentation procedures on clinical, radiographic and aesthetic outcomes, (ii) reliability and validity of outcome measures and methods of assessment and (iii) PROMs applied in clinical studies for soft tissue augmentation procedures at dental implant sites. Major findings, consensus statements, clinical recommendations and implications for future research were discussed in the group and approved during the plenary sessions. Results: The four reviews predominantly revealed: Soft tissue augmentation procedures in conjunction with immediate and delayed implant placement result in superior aesthetic outcomes compared to no soft tissue augmentation in the zone of aesthetic priority.Soft tissue augmentation procedures have a limited effect on marginal bone level changes compared to implant sites without soft tissue augmentation. Clinically relevant parameters (gingival index, mucosal recession) and plaque control improve at implant sites when the width of keratinised mucosa is increased.A variety of aesthetic indices have been described with good reliability. Pink Esthetic Score and Complex Esthetic Index are the most validated aesthetic indices for single implants, though. Superimposed digital surface scans are most accurate to assess profilometric tissue changes.PROMs following soft tissue augmentation procedures have been assessed using various forms of questionnaires. Soft tissue augmentation had a limited effect on PROMs. Conclusions: Soft tissue augmentation procedures are widely applied in conjunction with implant therapy. Depending on the indication of these interventions, clinical, radiographic and aesthetic outcomes may improve, whereas the effect on PROMs is limited. [ABSTRACT FROM AUTHOR]

Objectives: The task of working Group 2 at the 6th Consensus Meeting of the European Association for Osseointegration was to comprehensively assess the effects of soft tissue augmentation procedures at dental implant sites on clinical, radiographic and patient‐reported outcome measures (PROMs) including an overview on available outcome measures and methods of assessment. Materials and methods: Three systematic reviews and one critical review were performed in advance on (i) the effects of soft tissue augmentation procedures on clinical, radiographic and aesthetic outcomes, (ii) reliability and validity of outcome measures and methods of assessment and (iii) PROMs applied in clinical studies for soft tissue augmentation procedures at dental implant sites. Major findings, consensus statements, clinical recommendations and implications for future research were discussed in the group and approved during the plenary sessions. Results: The four reviews predominantly revealed: Soft tissue augmentation procedures in conjunction with immediate and delayed implant placement result in superior aesthetic outcomes compared to no soft tissue augmentation in the zone of aesthetic priority.Soft tissue augmentation procedures have a limited effect on marginal bone level changes compared to implant sites without soft tissue augmentation. Clinically relevant parameters (gingival index, mucosal recession) and plaque control improve at implant sites when the width of keratinised mucosa is increased.A variety of aesthetic indices have been described with good reliability. Pink Esthetic Score and Complex Esthetic Index are the most validated aesthetic indices for single implants, though. Superimposed digital surface scans are most accurate to assess profilometric tissue changes.PROMs following soft tissue augmentation procedures have been assessed using various forms of questionnaires. Soft tissue augmentation had a limited effect on PROMs. Conclusions: Soft tissue augmentation procedures are widely applied in conjunction with implant therapy. Depending on the indication of these interventions, clinical, radiographic and aesthetic outcomes may improve, whereas the effect on PROMs is limited. [ABSTRACT FROM AUTHOR]

Objective: To determine whether combining cross‐linked (CL) collagen‐integrated xenogeneic bone blocks stabilized with the fixation of resorbable collagen membranes (CM) can enhance guided bone regeneration (GBR) in the overaugmented calvarial defect model. Materials and Methods: Four circular defects with a diameter of 8 mm were prepared in the calvarium of 13 rabbits. Defects were randomly assigned to receive one of the following treatments: (i) non‐cross‐linked (NCL) porcine‐derived collagen‐embedded bone block covered by a CM without fixation (NCL + unfix group); (ii) NCL bone block covered by CM with fixation using bone‐tack (NCL + fix group); (iii) cross‐linked (CL) porcine‐derived collagen‐embedded bone block covered by CM without fixation (CL + unfix group); and (iv) CL bone block covered by CM with fixation using bone‐tack fixation (CL + fix group). The efficacy of GBR was assessed through histological and molecular analyses after 2 and 8 weeks. Results: At 2 weeks, there were no significant differences in histologically measured areas of newly formed bone among the groups. At 8 weeks, however, the CL + fix group exhibited a larger area of new bone (5.08 ± 1.09 mm2, mean ± standard deviation) compared to the NCL + unfix (1.62 ± 0.42 mm2; p <.0083), NCL + fix (3.97 ± 1.39 mm2) and CL + unfix (2.55 ± 1.04 mm2) groups. Additionally, the expression levels of tumour necrosis factor‐alpha, fibroblast growth factor‐2, vascular endothelial growth factor, osteocalcin and calcitonin receptor were significantly higher in the CL + fix group compared to the other three groups (p <.0083). Conclusion: Cross‐linked bone blocks stabilized with collagen membrane fixation can significantly enhance GBR. [ABSTRACT FROM AUTHOR]

Information regarding profilometric changes at a soft tissue level following implant placement with different protocols is insufficient. Therefore, this study aimed to comparatively investigate the profilometric tissue changes with respect to late implant placement following alveolar ridge preservation (LP/ARP) and early implantation (EP) in periodontally compromised non-molar extraction sites. Sixteen patients were randomly assigned to the following groups: implant placement 4 months post-ARP (group LP/ARP) and tooth extraction and implant placement 4–8 weeks post-extraction (group EP). Dental impressions were obtained immediately after final prosthesis insertion and at 3, 6, and 12 months. At the time of implant placement, bone augmentation was performed in the majority of the patients. Profilometric changes of the tissue contour were minimal between the final prosthesis insertion and 12 months in the mid-facial area (0.04–0.35 mm in group LP/ARP, 0.04–0.19 mm in group EP). The overall tissue volume increased in both groups (1.70 mm3 in group LP/ARP, 0.96 mm3 in group EP). In conclusion, LP/ARP and EP led to similar stability of the peri-implant tissue contour between the final prosthesis insertion and at 12 months. Moreover, the change of peri-implant tissue on the soft tissue level was minimal in both modalities. [ABSTRACT FROM AUTHOR]

Objectives: To compare two ridge preservation techniques and spontaneous healing in terms of soft tissue thickness, contour changes, and soft tissue handling two months after tooth extraction. Methods: Thirty‐six patients were included with buccal bone plate dehiscences of up to 50% after single‐tooth extraction in the esthetic zone. They were randomly assigned to receive one of three procedures: a deproteinized bovine bone mineral with 10% collagen (DBBM‐C) covered with a collagen matrix (DBBM‐C/CM), DBBM‐C alone, or spontaneous healing (SH). Two months later, the status of soft tissue healing was assessed, and the thickness of the mucosa was measured at the center of the site. Thereafter, implants were placed and the need for further guided bone regeneration (GBR) to cover exposed implant surfaces was assessed. Results: Thirty‐six patients were evaluated at the day of implant placement. An invagination of the soft tissues was recorded in 41.7% (n = 12), 53.8% (n = 13), and 90.9% (n = 11) of the sites in groups DBBM‐C/CM, DBBM‐C, and SH, respectively. The median thickness of the mucosa measured was 3.0 mm in group DBBM‐C/CM, 2.1 mm in group DBBM‐C, and 1.5 mm in group SH. Additional GBR was necessary in 66.7% (n = 12), 53.8% (n = 13), and 90.9% (n = 11) of the sites in groups DBBM‐C/CM, DBBM‐C, and SH, respectively. Conclusions: The present explorative study revealed slight tendencies for more favorable soft tissue conditions with less invaginations as well as increased soft tissue volume and thickness in groups having received an alveolar ridge preservation procedure compared to spontaneously healed sites at 8 weeks of healing. [ABSTRACT FROM AUTHOR]

Aim: To assess mid‐term clinical, radiographic and profilometric outcomes at implant sites, previously grafted with a volume‐stable collagen matrix (VCMX) or an autogenous subepithelial connective tissue graft (SCTG). Methods: VCMX or SCTG were randomly applied to single implant sites in 20 patients. Following abutment connection and insertion of final reconstructions (baseline), patients were re‐examined at 6 months (6M), at 1 year (FU‐1) and at 3 years (FU‐3). Measurements included the following: clinical data, radiographic measurement of first bone to implant contact (fBIC), soft tissue thickness and volumetric outcomes. Non‐parametric tests and estimates were applied for the statistical analysis. Results: The median buccal mucosal thickness increased by 0.5 mm (Q1: ‐0.5; Q3: 1.25) (VCMX) (p =.281) and by 0.8 mm (Q1: 0.0; Q3: 2.5) (SCTG) (p =.047) between BL and FU‐3 (intergroup p =.303). The profilometric changes of the buccal soft tissues demonstrated a median decrease between BL and FU‐3 of −0.2 mm (Q1: −0.5; Q3: −0.1) (p =.039) for VCMX and a decrease of −0.1 mm (Q1: −0.8; Q3: 0.1) (p =.020) for SCTG, respectively (intergroup p =.596). Peri‐implant soft tissues and bone levels remained healthy throughout the entire study period. PROMs did not show any significant differences between the groups nor significant changes over time. Conclusion: Minimal changes of the peri‐implant tissue contour as well as of the soft tissue thickness were observed at implant sites previously grafted with VCMX or SCTG. [ABSTRACT FROM AUTHOR]

Aim: To investigate the effect of three treatment modalities on the gain of keratinized tissue (KT) at tooth and implant sites in dogs. Materials and Methods: In five dogs, the distal roots of the mandibular second, third and fourth premolars were extracted, while the mesial roots were maintained. After 2 months of healing, implants were placed with KT excision. After another 2 months of healing, free gingival grafts, collagen‐based matrices and apically positioned flap only were applied. The height of KT was measured during implant placement, immediately before soft‐tissue grafting and after 10, 30 and 60 days. Results: Two months after KT excision, spontaneous KT regrowth was greater at tooth sites than at implant sites (median, 2.0 mm vs. 1.1 mm). The outcomes of soft‐tissue grafting at implant sites favoured the free gingival graft treatment, with a greater final median height (5.0–5.5 mm) and increase in KT (4.0–4.2 mm). Locations of the recipient sites significantly influenced KT regeneration at both tooth and implant sites. Conclusions: At implant sites, the free gingival graft treatment led to higher KT regeneration. At tooth sites, however, the differences between the three treatment modalities seemed clinically irrelevant. [ABSTRACT FROM AUTHOR]

Objectives: To test whether or not the use of a xenogeneic block loaded with rhBMP‐2 results in superior radiological and profilometric outcomes compared to an autogenous bone block. Materials and methods: Twenty‐four patients randomly received a xenogeneic block loaded with rhBMP‐2 (test) or an autogenous bone block (control) for primary augmentation. The ridge width (RW) was evaluated by means of a CBCT scan after augmentation surgery and at 4 months, prior to implant placement. Surface scans were taken prior to augmentation and at 4 months for profilometric analyses. Data were analyzed with Wilcoxon‐signed rank test, Mann–Whitney test, or nonparametric ANOVA models. Results: The median RW after augmentation amounted to 7.13 mm (Q1 = 6.02; Q3 = 8.47) for test and 6.86 mm (Q1 = 5.99; Q3 = 8.95) for control. During 4 months of healing, the total RW decreased statistically significantly and measured 5.35 mm (Q1 = 4.53; Q3 = 6.7) for test and 5.15 mm (Q1 = 3.57; Q3 = 7.24) for control (p = 0.0005). The differences between the groups were not statistically significant (p > 0.5899). The buccal soft tissue contour slightly increased for test (0.83 mm; Q1 = 0.62; Q3 = 1.87) and control (1.16 mm; Q1 = 0.50; Q3 = 1.44). Conclusions: Both treatment modalities successfully increased the ridge width to a similar extent. The shrinkage during healing was not greater in the test than in the control group. The impact of hard tissue augmentation on the soft tissue contour was, however, minimal. [ABSTRACT FROM AUTHOR]

Objective: To histologically and radiographically evaluate soft (primary outcome) and hard tissue integration of two‐piece titanium and zirconia dental implants with/without buccal dehiscence defects. Materials & methods: In six dogs, five implants were randomly placed on both sides of the mandible: (a) Z1: a zirconia implant (modified surface) within the bony housing, (b) Z2: a zirconia implant (standard surface) within the bony housing, (c) T: a titanium implant within the bony housing, (d) Z1_D: a Z1 implant placed with a buccal bone dehiscence (3 mm in height, identical width to implant body), and (e) T_D: a titanium implant placed with a buccal bone dehiscence. Two weeks of healing and 6 months of loading were applied on each hemi‐mandible, respectively. Results: The median level of the margo mucosae shifted more apically over time in all groups (borderline statistical significance in groups Z1_D: −0.52 mm and T_D: −1.26 mm). The median height of the peri‐implant mucosa in groups Z1_D and T_D was greatest at 2 weeks and 6 months, but the linear change in the peri‐implant mucosa was statistically significant only for group T_D over time (−1.45 mm). Z1 demonstrated a higher bone‐to‐implant contact compared to Z2 and T. Minimal change of radiographic marginal bone levels in all groups was observed (<1 mm). Conclusion: When buccal dehiscence was presented, titanium implants presented significant loss of peri‐implant mucosal height compared to zirconia implants with a modified surface, due to greater apical shift of the margo mucosae. A modified zirconia surface enhanced osseointegration. [ABSTRACT FROM AUTHOR]

Objectives: To analyse the evidence regarding the efficacy of lateral bone augmentation procedures in terms of defect resolution in cases of horizontal ridge deficiencies after implant placement. Materials and Methods: Included studies met the following inclusion criteria: randomized controlled trials (RCTs) or controlled clinical trials (CCTs), re‐entry procedure to assess defect resolution, minimum of 10 patients (5 per group). Meta‐analyses were performed whenever possible, including subgroup analysis based on membranes and grafting materials. Results: Twenty‐eight publications (20 short‐term, 8 follow‐up studies) were included. The most often used type of intervention was a xenogeneic particulated grafting material (XE) and a resorbable collagen membrane (CM). The mean defect height at baseline amounted to 5.1 mm (range 2.4–7.8) and decreased to a mean of 0.9 mm (range 0.2–2.2) at re‐entry, and the mean defect resolution was 81.3% (range 56.4%–97.1%). Defect height reduction was not significantly different using CM+XE as control treatment compared to the combined data of the respective test groups [n = 11; weighted mean difference (WMD) = −0.006 mm; 95% CI, −0.61, 0.60; p = 0.985]. The absence of any lateral bone augmentation was less favourable than the conjunction of a membrane and a bone grafting material (n = 1; MD = −1.96 mm; 95% CI, −3.48, −0.44; p = 0.011). The lack of a grafting material was less favourable than the conjunction of grafting material and membrane (n = 1; MD = −2.44 mm; 95% CI, −4.53, −0.35; p = 0.022), and the addition of a membrane compared to a grafting material alone was more favourable (n = 3; WMD = 0.97 mm; 95% CI, 0.31, 1.64; p = 0.004). Conclusions: Lateral bone augmentation is a successful treatment modality. For optimal defect height reduction, a barrier membrane and a grafting material should be combined. [ABSTRACT FROM AUTHOR]

Aims: To compare the radiographic marginal bone levels of implants placed in sites previously augmented with autogenous bone grafts and implants placed in native bone. Secondary outcomes included: implant survival, periodontal/peri‐implant parameters as well as short‐ and long‐term patient‐reported outcome measures. Materials and methods: The study was designed as a case–control study including 38 patients equally distributed into two groups (previously augmented with autogenous bone blocks [AB] and implants placed in native bone [NB]). In total, 67 implants were placed. Clinical, radiographic and patient‐reported outcome measures (PROMs), and complication rates were assessed based on a chart review and at a follow‐up examination (≧5 years after implant placement). Nonparametric mixed models were applied for the comparison of the two groups because of the clustered data. The data were analyzed descriptively, and p‐values were calculated using nonparametric mixed models to account for the clustered data. Results: The mean follow‐up time was 10.2 years (range 6–13 years; AB) and 8.3 years (range 5–16 years; NB). One implant was lost in group NB (97.5% survival rate) and none in group AB (100%). Following primary augmentation, six major complications (wound dehiscences, acute pulpitis, intra‐ and extraoral sensitivity disturbances) were observed at the donor sites. At time of implant placement, only minimal complications occurred and only in group NB. Median marginal bone levels at the follow‐up were significantly higher in group NB (1.15; Q1: 0.50 mm/Q3: 1.83 mm) than in group AB (1.58; Q1: 1.01 mm/Q3: 2.40 mm; p = 0.0411). Probing depth, bleeding on probing and recession values were similar in both groups. PROMs revealed high visual analog scale values (i.e., high satisfaction) for both procedures. Conclusions: Dental implants placed in sites augmented with autogenous bone or in native bone revealed healthy peri‐implant tissues after 5–16 years. Marginal bone levels were significantly higher for implant placed in native bone. Complications following primary augmentation encompassed every third patient but were mostly transient. [ABSTRACT FROM AUTHOR]

Objective: To test whether or not topically administered recombinant human epidermal growth factor (rhEGF) accelerates the early healing phase of oral soft tissue wounds. Methods: One day following the creation of palatal defects (n = 6/animal), 14 dogs were allocated to one of the following five groups: spontaneous healing (SH), vehicle ointment (V), vehicle ointment + rhEGF at concentrations of 1 μg/g (EGF1), 10 μg/g (EGF10) or 50 μg/g (EGF50). Topical administration of ointments was repeated twice per day until sacrifice at days 8 and 16. Wound area was clinically monitored. Keratinocytes proliferation (Ki67‐immunolabelling), inflammatory response (IR) and areas of collagen (C) and granulation tissue (GT) were histologically measured. Kruskal–Wallis test with Dunnett correction was used for multiple group statistical comparisons. Results: Clinically, in comparison with SH, a significantly smaller wound area was observed in groups EGF1 and EGF10 at day 8 (p < 0.05). At day 16, wound closure reached 97.8% in group EGF1 compared to 83.2% in group SH, albeit no statistically different. Histologically, at day 8, significantly more GT was observed in group EGF10 compared to all other groups (p < 0.05). At day 16, in addition to a higher Ki67‐immunolabelling, groups EGF1 and EGF10 demonstrated a significant decrease in GT and IR with more deposition of C compared to the other groups (p < 0.05). Conclusion: Application of rhEGF enhanced the early healing of acute oral soft tissue wounds compared to SH, predominantly at concentrations of 1 and 10 μg/g. [ABSTRACT FROM AUTHOR]

Objectives: To analyze the effect of veneering of the submucosal part of zirconia abutments and the type of retention (cemented vs screw‐retained) on clinical, microbiological, and histological outcomes of single‐tooth implant crowns. Material and Methods: A total of 44 patients with a single missing tooth to be replaced by an implant in the anterior region participated in the study. Implants were randomly assigned to receive zirconia‐based CAD/CAM reconstructions using either one of four treatment modalities: cement‐retained with submucosal veneering (CR‐P), cement‐retained without submucosal veneering (CR‐W), screw‐retained with submucosal veneering (SR‐P), and screw‐retained without submucosal veneering (SR‐W). Clinical parameters were assessed at baseline (after crown insertion), at 6 and 12 months. Histological and microbiological analyses were performed at 6 months. Descriptive statistics and the Kruskal‐Wallis test were applied. Results: The clinical evaluation revealed, in general, stable peri‐implant soft tissues with minimal differences for all measured parameters between the four groups, except for bleeding on probing with the two cemented groups exhibiting higher values at 12 months (35.0% ± 26.5% for CR‐W and 25.0% ± 38.8% for CR‐P versus 13.1 ± 14.8 for SR‐W and 13.0 ± 18.2 for SR‐P). The descriptive and semi‐quantitative histology showed a trend for a higher inflammatory reaction in the two cemented (a medium to high number of inflammatory cells) compared to the screw‐retained groups (low number of inflammatory cells) at 6 months. The microbiological test demonstrated low bacterial counts and a similar distribution in between the groups except for two species (Tannerella forsythia and Peptostreptococcus micros) that were found in higher counts in the cemented groups at 6 months. Conclusion: Submucosal veneering of zirconia abutments did not negatively affect the health of the peri‐implant tissues. The cemented groups, though, did show a clinical and histological trend to higher levels of inflammation. [ABSTRACT FROM AUTHOR]

Aim: To compare the implant survival rate between short dental implants and standard length implants placed in combination with bone grafting at 5 years of loading. Methods: This multicentre study enrolled 101 patients (137 implants) with a posterior maxillary bone height of 5–7 mm. Patients randomly received either short implants (6 mm; GS) or long implants (11–15 mm) with sinus grafting (GG). Six months later, implants were loaded with single crowns and patients re‐examined at 1, 3 and 5 years of loading. Outcomes included: implant survival, marginal bone levels (MBLs), biological and technical parameters and patient‐reported outcome measures (OHIP‐49 = Oral Health Impact Profile). Statistical analysis was performed using a non‐parametric approach. Results: At 5 years, 90 patients (124 implants; GS: 60; GG: 64) were re‐examined (drop‐out rate 10%). Patient‐level implant survival rates were 98.5% (GS; 1 implant failure) and 100% (GG; p = 0.49). Mean MBLs were 0.54 mm ± 0.87 (GS) and 0.46 mm ± 1.00 (GG; p = 0.34). Biological and technical parameters were not significantly different (p > 0.05). Median overall OHIP‐49 scores improved significantly up to 5 years in both groups (GS: p = 0.03; GG: p = 0.00; intergroup comparison p = 0.11). Conclusions: Both treatment modalities were suitable for implant therapy in the atrophied posterior maxilla revealing no differences in terms of survival rates, marginal bone levels (changes), patient‐reported outcomes and technical/biological complications. [ABSTRACT FROM AUTHOR]

Objectives: To assess the early histological, microbiological, radiological, and clinical response to cemented and screw‐retained all‐ceramic single‐tooth implant‐supported reconstructions. Materials and methods: Patients with single‐tooth implants were randomly allocated to receive a cemented lithium disilicate crown on a customized zirconia abutment (CEM) or a screw‐retained crown with a directly veneered zirconia abutment (SCREW). At the screening visit, at crown insertion and at the 6‐month follow‐up, clinical parameters were measured at the implant and the contralateral tooth. Marginal bone levels, technical parameters, and esthetic outcomes were measured at the implants. At the 6‐month follow‐up, a microbiological test was performed and a soft tissue biopsy was harvested at the implants for histological analysis. Inflammatory cells and fibroblasts/‐cytes were analyzed at the level of the sulcular epithelium, junctional epithelium, and connective tissue. The histological parameters were analyzed by means of a linear mixed model. Results: Thirty‐three patients completed the study, and implant and crown survival rates were 100% at 6 months. Histologically, the number of inflammatory cells tended to be higher in group CEM (p > 0.05). Moreover, significantly less inflammatory cells and fibroblasts/‐cytes were found in the sulcular epithelium compared to the junctional epithelium and supracrestal connective tissue (p < 0.001). Four patients were tested positive for periodontal marker pathogens at the 6‐month follow‐up, and three of them belonged to group CEM. From crown insertion to the 6‐month follow‐up, median marginal bone levels changed only minimally and measured 0.31 and 0.32 mm in group CEM and 0.47 and 0.36 mm in group SCREW, respectively. Clinical and esthetic parameters remained stable over time and were comparable between natural teeth and implants as well as between the groups. Conclusions: Cemented reconstructions were associated with more inflammatory cells, and more patients were diagnosed with periodonto‐pathogens. Both types of reconstructions resulted in similar radiological (marginal bone levels) and clinical outcomes (bleeding on probing and probing depth). [ABSTRACT FROM AUTHOR]

Objectives: This work aimed to investigate the effectiveness and predictability of different treatment modalities for gain of keratinized tissue (KT) in fully edentulous jaws prior to dental implant placement: apically positioned flap (APF), APF plus xenogeneic collagen matrix (XCM), and APF plus free gingival graft (FGG).Materials and methods: In fully edentulous patients with insufficient zones of KT at the prospective implant positions, four treatment modalities were performed in the lower jaw: APF, XCM, FGG, and an untreated control group (control). APF and XCM were applied in the first molar positions, FGG and control in the canine positions. Assessed outcomes up to 3 months post-surgery included changes in width of KT (over a 3-month period), histomorphometric analysis of harvested soft-tissue biopsies (at 3 months postoperatively), and patient-reported outcomes measures (PROMs).Results: For the primary outcome, changes in KT width demonstrated an increase of 1.93 ± 1.6 mm (APF), whereas XCM and FGG showed an increase of 4.63 ± 1.25 mm and 3.64 ± 2.01, respectively. Histomorphometric analyses revealed a thickness of the epithelium ranging between 375 ± 122 μm (APF), 410 ± 116 μm (XCM), 336 ± 122 μm (FGG), and 413 ± 109 μm (control). All biopsies showed a regular muco-periosteal structure with a keratinized epithelium of comparable thickness in all groups.Conclusion: All three methods were suitable to increase the width of KT, although APF alone rendered roughly 50% less gain compared to XCM and FGG.Clinical relevance: The use of XCM in conjunction with an APF represents a valuable treatment option for the gain of keratinized tissue in edentulous sites. [ABSTRACT FROM AUTHOR]

The aim of the present study was to investigate the effect of hypoxia-inducible factor 1α (HIF1A) on the early healing (4 weeks) of extraction sockets exhibiting partial loss of the labial bone. Two extraction sockets of the maxillary incisors from each of six dogs were assigned to two treatment modalities: deproteinized bovine bone mineral (i) with 10% collagen (DBBM-C) soaked with HIF1A and covered by a collagen membrane (CM) (HIF group) or (ii) treated with DBBM-C only and covered by a CM (control group). Microcomputed tomography revealed some degree of collapse of the labial contour. The totally augmented volume and new bone volume did not differ significantly between two groups (P>0.05). The histological analysis revealed that the apical area of the socket was mostly filled with newly formed bone, while there was less newly formed bone in the coronal area and incomplete cortex formation. The histomorphometric analysis revealed that the area of newly formed bone was significantly larger in the HIF group than the control group (12.16±3.04 versus 9.48±2.01 mm2, P<0.05), while there was no significant intergroup difference in the total augmented area. In conclusion, even though DBBM-C soaked with HIF1A enhanced histomorphometric bone formation, this intervention did not demonstrate superiority in preventing ridge shrinkage compared to DBBM-C alone. Clinical relevance of these findings should be further studied. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To review the dental literature in terms of soft tissue augmentation procedures and their influence on peri‐implant health or disease in partially and fully edentulous patients. Methods: A MEDLINE search from 1966 to 2016 was performed to identify controlled clinical studies comparing soft tissue grafting versus no soft tissue grafting (maintenance) or two types of soft tissue grafting procedures at implant sites. The soft tissue grafting procedures included either an increase of keratinized tissue or an increase of the thickness of the peri‐implant mucosa. Studies reporting on the peri‐implant tissue health, as assessed by bleeding or gingival indices, were included in the review. The search was complemented by an additional hand search of all selected full‐text articles and reviews published between 2011 and 2016. The initial search yielded a total number of 2,823 studies. Eligible studies were selected based on the inclusion criteria (finally included: four studies on gain of keratinized tissue; six studies on gain of mucosal thickness) and quality assessments conducted. Meta‐analyses were applied whenever possible. Results: Soft tissue grafting procedures for gain of keratinized tissue resulted in a significantly greater improvement of gingival index values compared to maintenance groups (with or without keratinized tissue) [n = 2; WMD = 0.863; 95% CI (0.658; 1.067); p < .001]. For final marginal bone levels, statistically significant differences were calculated in favor of an apically positioned flap (APF) plus autogenous grafts versus all control treatments (APF alone; APF plus a collagen matrix; maintenance without intervention [with or without residual keratinized tissue]) [n = 4; WMD = −0.175 mm; 95% CI: (−0.313; −0.037); p = .013]. Soft tissue grafting procedures for gain of mucosal thickness did not result in significant improvements in bleeding indices over time, but in significantly less marginal bone loss over time [WMD = 0.110; 95% CI: 0.067; 0.154; p < .001] and a borderline significance for marginal bone levels at the study endpoints compared to sites without grafting. Conclusions: Within the limitations of this review, it was concluded that soft tissue grafting procedures result in more favorable peri‐implant health: (i) for gain of keratinized mucosa using autogenous grafts with a greater improvement of bleeding indices and higher marginal bone levels; (ii) for gain of mucosal thickness using autogenous grafts with significantly less marginal bone loss. [ABSTRACT FROM AUTHOR]

Objectives: The objective of this study was to determine the validity of a graft-free sinus floor elevation (SFE) procedure with simultaneous placement of recombinant morphogenetic protein-2 (rhBMP-2)-coated implants compared to uncoated control implants.Methods: In 10 rabbits, SFE was performed on both sides. Dental implants were randomly placed in the sinus filled with a blood clot. Test implants were coated with rhBMP-2, whereas in the control group, implants were uncoated. Micro-computed tomographic and histomophometric analyses were performed at 4 and 8 weeks, including measurement for newly formed bone height (NBHm).Results: Bone formation was evident along the implant surfaces up to the apex in test, but limited in control implants at 4 weeks. NBHm amounted to 5.1 mm (Q1 = 4.1; Q3 = 5.3) for test implants and to 3.4 mm (2.6; 3.7) for control implants at 4 weeks. NBHm then decreased to 8 weeks (3.4 mm (3.3; 3.7)) for test implants, whereas in control sites, NBHm increased slightly to 4.4 mm (4.1; 4.5) (p = 0.1250; p = 0.6250).Conclusions: Implants coated with rhBMP-2 presented a strong osteogenic reaction at 4 weeks with more favorable outcomes in terms of bone formation along the implant surface up to the apex compared to uncoated control implants. Remodeling and resorption process between 4 and 8 weeks did not further improve the outcomes in the test, but in the control group.Clinical relevance: The use of rhBMP-2-coated implants in a graft-free SFE might show an advantage in early implant stability to prevent collapse of membrane. However, a potential clinical benefit still needs to be proven. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To test whether or not the use of a xenogeneic block loaded with recombinant human bone morphogenetic protein‐2 (rhBMP‐2) results in different bone quantity and quality compared to an autogenous bone block. Materials and Methods: Twenty‐four patients with insufficient bone volume for implant placement were randomly assigned to two treatment modalities: a xenogeneic bone block loaded with rhBMP‐2 (test) and an autogenous bone block (control). The horizontal ridge width was evaluated prior to augmentation, after augmentation and at 4 months. Patient‐reported outcome measures (PROMs) were assessed at suture removal and at 4 months. Biopsies were obtained at 4 months and histologically evaluated. Intergroup comparisons were tested by a two‐sided Wilcoxon–Mann–Whitney test, intra‐group comparisons were performed with Wilcoxon‐signed rank test, and all categorical variables were tested with Chi‐squared tests. Results: One autogenous bone block failed. This patient was replaced, and in all subsequently treated 24 patients, implant placement was possible 4 months later. The median ridge width increased from 4.0 mm (Q1 = 2.0; Q3 = 4.0) (test) and 2.0 mm (Q1 = 2.0; Q3 = 3.0) (control) to 7.0 mm (Q1 = 6.0; Q3 = 8.0) (test) and 7.0 mm (Q1 = 6.0; Q3 = 8.0) (control) at 4 months (intergroup p > .05). A higher morbidity was reported at the augmented site in the control group during surgery. Sensitivity was more favourable in the test than that in the control group at 4 months. The biopsies revealed more mineralized tissue in the control group (p < .0043). Conclusions: Both treatment modalities were successful in regenerating bone to place dental implants. PROMs did not reveal any significant differences between the groups except for pain during surgery at the recipient site (in favour of the test group). Histologically, a higher amount of mineralized tissue was observed for the control group at 4 months. [ABSTRACT FROM AUTHOR]

Aim To test whether guided bone regeneration ( GBR) of peri-implant defects at zirconia (ZrO2) implants differs from GBR at titanium (Ti) implants regarding the bone integration of the implant and of the grafting material. Materials and methods Maxillary premolars and molars were extracted in seven dogs. After 5 months, four semi-saddle bone defects were created in each maxilla. Implant placement and simultaneous GBR were performed using the following randomly assigned modalities: (1) ZrO2 implant + deproteinized bovine bone mineral ( DBBM) granules + a collagen membrane ( CM), (2) ZrO2 implant + DBBM with 10% collagen matrix + CM, (3) ZrO2 implant + DBBM block + CM, and (4) Ti implant + DBBM granules + CM. After 3 months, one central histological section of each site was prepared. Histomorphometrical assessments were performed evaluating the augmented area ( AA) within the former bone defect (primary outcome), the area of new bone ( NB), bone substitute ( BS), and non-mineralized tissue ( NMT) within AA in mm2. In addition, the distance between the most coronal bone-to-implant contact and the margin of the former bone defect ( fBIC- DEF), and the bone-to-implant contact fraction ( BIC) were measured in mm. Results AA measured 8.6 ± 4.0 mm2 for ZrO2 implant + DBBM granules, 4.7 ± 1.6 mm2 for ZrO2 implant + DBBM-collagen, 5.1 ± 1.9 mm2 for ZrO2 implant + DBBM block, and 7.6 ± 2.8 mm2 for Ti implant + DBBM granules. There were no statistically significant differences between the treatment modalities ( P > 0.05). NB reached 2.0 ± 1.7 mm2 for ZrO2 implant + DBBM granules, 0.9 ± 0.9 mm2 for ZrO2 implant + DBBM-collagen, 2.1 ± 0.9 mm2 for ZrO2 implant + DBBM block, and 0.8 ± 0.6 mm2 for Ti implant + DBBM granules. fBIC- DEF amounted to 2.1 ± 1.7 mm2 for ZrO2 implant + DBBM granules, to 2.7 ± 1.1 mm2 for ZrO2 implant + DBBM-collagen, to 2.9 ± 1.2 mm2 for ZrO2 implant + DBBM block, and to 3.4 ± 0.4 mm2 for Ti implant + DBBM granules. BIC measured 70 ± 19% for ZrO2 implant + DBBM granules, 69 ± 22% for ZrO2 implant + DBBM-collagen, 77 ± 30% for ZrO2 implant + DBBM block, and 66 ± 27% for Ti implant + DBBM granules. Conclusions The findings of the present pilot study suggest that zirconia and titanium implants grafted with DBBM granules and covered with a collagen membrane do not perform differently regarding the augmented ridge contour, the NB formation, and the implant osseointegration. [ABSTRACT FROM AUTHOR]

Objectives Improvement in localized bone regeneration is needed to avoid the use of autogenous tissue. For that purpose, the use biologic mediators was proposed. The aim was to test whether or not one of two biologic mediators, recombinant human bone morphogenetic protein-2 (rh BMP-2) or recombinant platelet-derived growth factor (rh PDGF- BB), is superior to the other and to control groups for localized bone regeneration. Materials and Methods Four cylinders (height: 5 mm; diameter: 7 mm) were screwed on the parietal and frontal bones at the cranium in 12 rabbits. The cylinders either received (i) deproteinized bovine bone mineral ( DBBM) mixed rh BMP-2 ( DBBM/ BMP-2), (ii) DBBM mixed with rh PDGF- BB ( DBBM/ PDGF), (iii) DBBM ( DBBM), and (iv) empty control (control). Rabbits were euthanized at 2 and 8 weeks ( n = 6, respectively). Conventional histomorphometric and micro- CT analyses were performed. Parametric linear mixed models were applied for the analyses with Bonferroni correction for the multiple group comparisons. Results The area of bone regeneration (histology; AAHisto) at 2 weeks peaked for DBBM (41.91%) with statistically significantly greater values compared to DBBM/ PDGF and the control group ( P < 0.05). At 8 weeks, mean AAHisto values were 96.29% ( DBBM/ BMP-2), 46.37% ( DBBM/ PDFG), 39.66% ( DBBM), and 35.98% (control) ( DBBM/ BMP-2 vs. all groups ( P < 0.05)). At 8 weeks, bone regeneration was greatest for DBBM/ BMP-2 (35.62%) with statistically significant differences compared to all other groups ( P < 0.05). The area of bone regeneration (micro- CT; AAm- CT) at 2 weeks amounted to 43.87% ( DBBM/ BMP-2), 42.81% ( DBBM/ PDFG), 48.71% ( DBBM), and 0.96% (control). The control group demonstrated statistically significantly less AAm- CT compared to all groups ( P < 0.05). At 8 weeks, mean AAm- CT values were 63.65% ( DBBM/ BMP-2), 50.21% ( DBBM/ PDFG), 44.81% ( DBBM), and 4.57% (control) ( P > 0.05). Conclusions The use of rh BMP-2 significantly enhanced bone regeneration compared to all other groups including the group with rh PDGF- BB . [ABSTRACT FROM AUTHOR]

Objectives To test whether or not chemical and/or physical modifications of polyethylene glycol ( PEG) hydrogels influence degradation time, matrix/membrane stability, and integration into surrounding hard and soft tissues. Material and methods In 28 rabbits, six treatment modalities were randomly applied to six sites on the rabbit skull: a dense network PEG hydrogel ( PEG HD), a medium-dense network PEG hydrogel ( PEG MD), a medium-dense network PEG hydrogel modified with an RGD sequence ( PEG MD/ RGD), a medium-dense network PEG hydrogel modified with RGD with reduced carboxymethyl cellulose ( PEG MD/ RGD_ LV), a loose network PEG hydrogel modified with RGD ( PEG LD/ RGD), and a collagen membrane ( BG). Descriptive histology and histomorphometry were performed at 1, 2, 4, and 6 weeks. Results PEG HD revealed the highest percentage of residual matrix at all time points starting with 47.2% (95% CI: 32.8-63.8%) at 1 week and ending with 23.4% (95% CI: 10.3-49.8%) at 6 weeks. The hydrogel with the loosest network ( PEG LD/ RGD) was stable the first 2 weeks and then degraded continuously with a final area of 8.3% (95% CI: 3.2-21.2%). PEG HD was the most stable and densely stained membrane, whereas PEG MD and PEG LD matrices integrated faster, but started to degrade to a higher degree between 2 and 4 weeks. PEG MD degradation was dependent on the addition of RGD and the amount of CMC. Conclusions Chemical and/or physical modifications of PEG hydrogels influenced matrix stability. PEG MD/ RGD demonstrated an optimal balance between degradation time and integration into the surrounding soft and hard tissues. [ABSTRACT FROM AUTHOR]

Objectives The objective of this systematic review was to assess the 5-year and 10-year survival of resin -bonded fixed dental prostheses ( RBBs) and to describe the incidence of technical and biological complications. Materials and Methods An electronic MEDLINE search complemented by manual searching was conducted to identify prospective and retrospective cohort studies and case series on RBBs with a mean follow-up time of at least 5 years. Patients had to have been examined clinically at the follow-up visit. Assessment of the identified studies and data extraction were performed independently by two reviewers. Failure and complication rates were analyzed using robust Poisson regression models to obtain summary estimates of 5- and 10-year proportions. Results The search provided 367 titles and 87 abstracts. Full-text analysis was performed for 22 articles resulting in seven studies that met the inclusion criteria. Five articles were found through manual search, and 17 studies were provided from (Pjetursson et al. 2008, Clinical Oral Implants Research, 19, 131), resulting in an overall number of included studies of 29. Meta-analysis of these studies reporting on 2300 RBBs indicated an estimated survival of resin-bonded bridges of 91.4% (95 percent confidence interval [95% CI]: 86.7-94.4%) after 5 years and 82.9% (95% CI: 73.2-89.3%) after 10 years. A significantly higher survival rate was reported for RBBs with zirconia framework compared with RBBs from other materials. RBBs with one retainer had a significantly higher survival rate ( P < 0.0001) and a lower de-bonding rate ( P = 0.001) compared with RBBs retained by two or more retainers. Moreover, the survival rate was higher for RBBs inserted in the anterior area of the oral cavity compared with posterior RBBs. The most frequent complications were de-bonding (loss of retention), which occurred in 15% (95% CI: 10.9-20.6%) and chipping of the veneering material that was reported for 4.1% (95% CI: 1.8-9.5%) of the RBBs over an observation period of 5 years. Conclusion Despite the high survival rate of RBBs after 5 and 10 years, technical complications like de-bonding and minor chipping were frequent. RBBs with zirconia framework and RBBs with one retainer tooth showed the highest survival rate. [ABSTRACT FROM AUTHOR]

Objectives To test whether or not one of two biological mediators (recombinant human bone morphogenetic protein-2 (rhBMP-2) and recombinant human platelet-derived growth factor (rhPDGF-BB)) is superior to the other and compared with control groups for bone regeneration around implants based on histomorphometrical outcome measures. Materials and methods Box-type defects (10 × 5 × 5 mm) were prepared on the buccal sides of the left and right edentulous ridge in ten mongrel dogs. Implants were placed at each site, the defects either received (i) bovine-derived particulated bone mineral (DBBM) mixed with rhBMP-2 and a collagen membrane (CM) (DBBM/BMP-2), (ii) DBBM mixed with rhPDGF-BB and CM (DBBM/PDGF), (iii) DBBM and CM (DBBM) and (iv) empty control (control). Animals were euthanized post-surgery at 8 weeks and 16 weeks. Histomorphometrical analyses were performed. Results The mean percentages of regenerated area within total defect area amounted to 56.95% for DBBM/BMP-2, 48.86% for DBBM/PDFG, 33.44% for DBBM and 1.59% for control at 8 weeks, and 26.79% for DBBM/BMP-2, 23.78% for DBBM/PDFG, 30.21% for DBBM and 5.07% for control at 16 weeks with no statistically significant differences between the groups ( P > 0.05). The mean amount of regenerated bone was 26.97% for DBBM/BMP-2, 22.02% for DBBM/PDFG, 5.03% for DBBM and 1.25% for control at 8 weeks, and at 16 weeks, these values were lower in the two groups with biological mediators (DBBM/BMP-2 = 13.35%; DBBM/PDGF = 6.96%) and only slightly increased in group DBBM (10.68%) and the control group (4.95%) compared with 8 weeks. The first bone-to-implant contact values on the buccal side were minimal for DBBM/BMP-2 (0.57 mm) and maximal for control (3.72 mm) at 8 weeks. Conclusions The use of biological mediators (rhBMP-2 and rhPDGF-BB) can increase the amount of bone regeneration at dehiscence-type defects compared with controls at 8 weeks, but not at 16 weeks due to enhanced hard tissue remodeling processes. [ABSTRACT FROM AUTHOR]

Aim To test whether an equine bone substitute block used for guided bone regeneration ( GBR) of peri-implant defects differs from bovine block or particulate bone substitutes regarding the hard and soft tissue contours of the augmented ridge. Material & Methods Two semi-saddle bone defects were prepared in each side of the mandible of eight dogs, and one titanium implant was inserted into every defect. The defects were randomly allocated to receive one of the following treatments: bone augmentation by GBR using (1) particulate deproteinized bovine bone mineral ( DBBM) + a collagen membrane ( CM), (2) block DBBM + CM, (3) equine bone substitute block + CM, and (4) empty controls. After 4 months, the jaws were scanned by means of cone beam computed tomography ( CBCT). CBCT analysis was performed in one central and two lateral (mesial and distal) regions of interest ( ROI) of each site evaluating the horizontal thickness of the augmented hard tissue ( HThard tisue) and the total thickness of hard and soft tissue ( HTtotal). The Wilcoxon-Pratt signed rank test was used for statistical analysis. Results In the majority of ROIs, equine and bovine blocks rendered significantly higher values in HThard tissue and HTtotal than controls ( P < 0.05). Generally, equine blocks reached the highest values in HThard tissue and HTtotal followed by DBBM blocks and particulate DBBM. The differences in HThard tissue and HTtotal between GBR groups were not statistically significant ( P > 0.05). In the central ROI, HThard tissue at the level of the implant shoulder measured 1.7 ± 1.4 mm for equine blocks, 1.7 ± 1.0 mm for DBBM blocks, 0.9 ± 1.2 mm for particulate DBBM, and 0 ± 0 mm for controls. The corresponding values in the lateral ROI reached 1.9 ± 1.1 mm for equine blocks, 1.2 ± 0.8 mm for DBBM blocks, 1.0 ± 0.9 mm for particulate DBBM, and 0 ± 0 mm for controls. Conclusions GBR with bone substitute blocks lead to higher ridge dimensions than empty controls. The equine block with CM rendered the most favorable outcomes in hard and soft tissue contours followed by DBBM block and DBBM granulate with CM. [ABSTRACT FROM AUTHOR]

Background Zirconia abutments are frequently used for implant-supported single crowns. Even though demonstrating esthetic benefits compared to metal abutments, zirconia abutments lead to an increased brightness of the peri-implant mucosa compared to natural teeth and are not ideal from an esthetic point of view. Purpose To test whether or not a fluorescent hybrid zirconia abutment offers superior esthetics compared to a non-fluorescent one-piece zirconia abutment based on spectrophotometric analysis. Materials and Methods In 24 patients with 24 single-tooth implants, 2 types of reconstructions were fabricated: a directly veneered one-piece zirconia abutment/crown (control) and a directly veneered fluorescent hybrid zirconia abutment/crown (test). Spectrophotometric assessment was performed: prior to abutment insertion (WA), at abutment try-in (A), at the try-in of the final crowns (C). Color differences (Δ E) were assessed compared to the gingiva of natural teeth (T) and between the reconstructions. Results At abutment try-in, Δ E values were 8.49 ± 3.59 for AControl and 8.27 ± 4.03 for ATest compared to T. At crown insertion, Δ E values were 7.61 ± 4.03 for CControl and 8.32 ± 3.57 for CTest compared to T. The difference in Δ E values between AControl and ATest was 0.23 ± 2.54 ( P = .37), whereas the difference in Δ E values between CControl and CTest was −0.66 ±3.45 ( P = .48). For all cases with a mucosal thickness ≤2 mm, the comparison between CControl and CTest was significant in favor of the control group ( P = .03). Conclusions Both types of reconstructions were similar in terms of esthetics. Incases with a mucosal thickness of <2 mm, the soft tissue discoloration compared to the natural gingiva was more pronounced for the fluorescent hybrid zirconia reconstructions. [ABSTRACT FROM AUTHOR]

Objectives The aim of the study was to test whether or not the use of a polyethylene glycol (PEG) hydrogel with or without the addition of an arginylglycylaspartic acid (RGD) sequence applied as a matrix in combination with hydroxyapatite/tricalciumphosphate (HA/TCP) results in similar peri-implant bone regeneration as traditional guided bone regeneration procedures. Material and methods In 12 beagle dogs, implant placement and peri-implant bone regeneration were performed 2 months after tooth extraction in the maxilla. Two standardized box-shaped defects were bilaterally created, and dental implants were placed in the center of the defects with a dehiscence of 4 mm. Four treatment modalities were randomly applied: i)HA/ TCP mixed with a synthetic PEG hydrogel, ii)HA/ TCP mixed with a synthetic PEG hydrogel supplemented with an RGD sequence, iii)HA/ TCP covered with a native collagen membrane ( CM), iv)and no bone augmentation (empty). After a healing period of 8 or 16 weeks, micro- CT and histological analyses were performed. Results Histomorphometric analysis revealed a greater relative augmented area for groups with bone augmentation (43.3%-53.9% at 8 weeks, 31.2%-42.8% at 16 weeks) compared to empty controls (22.9% at 8 weeks, 1.1% at 16 weeks). The median amount of newly formed bone was greatest in group CM at both time-points. Regarding the first bone-to-implant contact, CM was statistically significantly superior to all other groups at 8 weeks. Conclusions Bone can partially be regenerated at peri-implant buccal dehiscence defects using traditional guided bone regeneration techniques. The use of a PEG hydrogel applied as a matrix mixed with a synthetic bone substitute material might lack a sufficient stability over time for this kind of defect. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether N-methyl-2-pyrrolidone (NMP) can decrease the dose of recombinant human bone morphogenetic protein-2 (rhBMP-2) in sinus augmentation of rabbits. In each of 15 rabbits, 2 sinuses were randomly grafted using 1 of 3 treatment modalities: (i) biphasic calcium phosphate (BCP; control), (ii) rhBMP-2-coated BCP (BMP), or (iii) rhBMP-2-coated BCP soaked in NMP solution (BMP/NMP). The rabbits were sacrificed 2 weeks postoperatively. Histologic and histomorphometric analyses were performed. Bone formation in all groups was predominantly located close to the access window and the lateral walls. Newly formed bone within the total augmented area (NBTA) was greatest in BMP/NMP (1.94±0.69 mm2), followed by BMP (1.50±0.72 mm2) and BCP (1.28±0.52 mm2) (P>0.05). In the center of the augmentation (NBROI_C) and the area close to the sinus membrane (NBROI_M), BMP/NMP produced the largest area of NB (NBROI_C: 0.10±0.11 mm2; NBROI_M: 0.17±0.08 mm2); the corresponding NB values for BCP were 0.05±0.05 mm2 and 0.08±0.09 mm2, respectively (P>0.05 for all comparisons). The effect of NMP on bone regeneration was inconsistent between the specimens. Adding NMP as an adjunct to rhBMP-2-coated BCP produced inconsistent effects on bone regeneration, resulting in no significant benefit compared to controls. [ABSTRACT FROM AUTHOR]

Aim To assess (i) bone regeneration around implants placed early in sites with or without ridge preservation and (ii) if the bone substitute material ( DBBM-C) has to be removed at implant placement. Materials and methods In eight beagle dogs, three sites were randomly assigned to ridge preservation ( DBBM-C plus collagen matrix ( CMX)) (two sites; RP) or spontaneous healing (1 site; SH). Four weeks later, in one of the RP sites, dental implants were placed without removing the DBBM-C ( RP1), whereas in RP2 and SH sites all non-integrated DBBM-C and/or granulation tissue were removed before implant placement and concomitant GBR. Histomorphometric outcomes were assessed at 4 and 12 weeks. Results The median buccal fBIC (first bone-to-implant contact) was located more apical in groups RP1: 1.34 mm (0.09; 2.96) and RP2: 1.41 mm (0.54; 2.72) than in group SH: 0.79 mm (0.26; 1.50) ( p = 0.452) at 4 weeks. At 12 weeks, median buccal fBIC values were for RP1: 0.88 mm (0.00; 2.33), for RP2: 0.16 mm (0.00; 1.33) and for SH: 0.00 mm (0.00; 0.98) ( p = 0.362). BIC values increased over 12 weeks in all groups. Conclusions Ridge preservation followed by early implant placement led to higher BIC values at 12 than at 4 weeks. There is no need to remove the biomaterial at implant placement to ensure osseointegration. No relevant differences were observed between the three groups for any outcome measure. [ABSTRACT FROM AUTHOR]

Aim To test whether the use of short dental implants (6 mm) results in an implant survival rate similar to that with longer implants (11-15 mm) in combination with sinus grafting. Methods This multicentre study enrolled 101 patients with partial edentulism in the posterior maxilla and a remaining bone height of 5-7 mm. Included patients were randomly assigned to receive short implants (6 mm; GS/group short) or long implants (11-15 mm) simultaneously with sinus grafting ( GG/group graft). Six months after implant placement ( IP), implants were loaded with single crowns ( PR) and patients were re-examined yearly thereafter. Assessed outcomes included: implant survival, marginal bone level changes ( MBL), probing pocket depth ( PPD), bleeding on probing (BoP) and plaque accumulation ( PCR) during 3 years of loading as well as recording of any adverse effects. In addition to descriptive statistics, statistical analysis has been performed for the two treatment modalities using a non-parametric approach. Results In 101 patients, 137 implants were placed. At the 3-year follow-up ( FU-3), 94 patients with 129 implants were re-examined. The implant survival rate was 100% in both groups. MBL at FU-3 was 0.45 mm ( GG) and 0.44 mm ( GS) ( p > 0.05). A statistically significant loss of MBL was observed in both GG (−0.43 ± 0.58 mm) and GS (−0.44 ± 0.56 mm) from IP to FU-3, and from PR to FU-3 in GG (−0.25 ± 0.58 mm) but not in GS (−0.1 ± 0.54 mm). PCR and BoP at FU-3 did not show any difference between the groups but for PPD ( p = 0.035). Conclusions Within the limitations of this study, implants with a length of 6 mm as well as longer implants in combination with a lateral sinus lift may be considered as a treatment option provided a residual ridge height of 5-7 mm in the atrophied posterior maxilla is present. [ABSTRACT FROM AUTHOR]

In recent years the scientific community has shown a clear interest in the esthetic outcome of implant treatment. The present paper provides an overview of the esthetic ratings that have been used in implant dentistry. A distinction can be made between objective evaluations by clinicians and subjective evaluations by patients. The former mainly include: midfacial and interproximal soft-tissue levels; two-dimensional/three-dimensional soft-tissue alterations; assessment of the color match between the natural dentition, on the one hand, and the peri-implant tissues and the reconstruction, on the other hand; and ordinal indices, such as the pink and white esthetic score. Patient's needs and judgment may differ from objective indicators of implant success and esthetics. As a result, assessing treatment on the basis of patient-reported outcomes measures should be considered important. Validated questionnaires have been used that mainly assess the impact of oral health on the overall well-being of individuals. The esthetic judgment of patients is usually based on nonstandardized questions with varying scoring methods, including visual analog scales, Likert and other category scales and open questions. The heterogeneity in scoring systems between studies may compromise proper comparison of objective and subjective esthetic outcomes between studies and therapeutic concepts. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to test whether or not soft tissue augmentation with a collagen matrix ( VCMX) leads to a similar increase in ridge width around dental implants compared to the use of an autogenous subepithelial connective tissue graft ( SCTG). Materials and Methods In 12 dogs, immediate dental implants were placed with simultaneous guided bone regeneration. Three months later, soft tissue volume augmentation was performed by randomly allocating three treatment modalities to these sites [ VCMX, SCTG, sham-operated group (control)]. Dogs were sacrificed at 1 ( n = 4), 2 ( n = 4) or 6 months ( n = 4). Descriptive histology and histomorphometric measurements for soft tissue thickness were performed on non-decalcified sections. Results The horizontal soft tissue thickness was maximal at the most coronal level (alveolar crest) at 1 month ( VCMX: 2.1 ± 1.6 mm; SCTG: 2.5 ± 1.7 mm; p = 0.877) and decreased until 6 months. At 6 months, the greatest mucosal thickness was at a level 3.5 mm below the crest ( VCMX: 0.8 ± 0.3 mm; SCTG: 0.7 ± 0.2 mm) ( p = 0.754). Control sites revealed no relevant soft tissue augmentation at any level and any time-point. Tissue integration for VCMX and SCTG were favourable with minimal inflammatory reactions. Conclusions Soft tissue volume augmentation at implant sites was obtained to a similar extent using VCMX and SCTG up to 2 months. Thereafter, degradation and remodelling processes were enhanced leading to a minimal increase in soft tissue thickness at 6 months for VCMX and SCTG. [ABSTRACT FROM AUTHOR]

Purpose The purposes of this study were to test whether or not veneering of the submucosal part of zirconia abutments can positively influence the esthetic outcome compared with nonveneered zirconia abutments; to evaluate the influence of the mucosal thickness on the esthetic outcomes of the veneered and nonveneered abutments; and to evaluate the thickness of the peri-implant mucosa compared with the thickness of the gingiva of contralateral tooth sites. Materials and Methods Forty-four single-tooth implants in 44 patients were randomly restored with either cemented ( CR) or screw-retained ( SR) reconstructions based on white zirconia abutments ( CR- W, SR- W) or pink-veneered zirconia abutments ( CR- P, SR- P). Esthetic outcome measurements were performed based on a spectrophotometric evaluation of the peri-implant mucosal color. In addition, the thickness of the mucosa was measured. A two-way analysis of variance was conducted to test the effect of veneering (pink vs white) and mucosa thickness (<2 mm vs ≥2 mm) on the calculated color difference Δ E for pooled data of CR and SR reconstructions ( p < .05). Results Analyses grouping the sites according to veneering of the abutments and mucosal thickness demonstrated less discoloration for sites with a veneered abutment irrespective of the mucosal thickness: ΔE 4.50 ± 1.93 (<2 mm) and ΔE 6.88 ± 2.45 (≥2 mm); CR- P, SR- P) compared with sites without veneering ΔE 9.72 ± 3.82 (<2 mm; CR- W, SR- W) and ΔE 8.31 ± 2.98 (≥2 mm). The differences between veneered and nonveneered abutments were significant ( p = .032). Conclusions Veneering of zirconia abutments with pink veneering ceramic positively influenced the peri-implant mucosal color. [ABSTRACT FROM AUTHOR]

Aim The aim of this study was to test whether or not a collagen matrix can improve early wound healing compared to spontaneous healing based on histological and immunohistologic analyses. Methods In 20 volunteers, 6 mm punch biopsies were harvested at the palate. A xenogeneic collagen matrix ( XCM) was sutured in one site; the other one was left untreated (control). Biopsies with a diameter of 8 mm were subsequently obtained at 4, 8, 15 and 29 days and histological and immunohistologic analyses were performed. Results At day 4, wound bed keratinization amounted to 12.4 ± 7.5% (control) and 18.0 ± 10.2% ( XCM). This increased up to day 8 (19.7 ± 25.5% control; 29.1 ± 8.0% XCM) and reached complete keratinization at day 15 in both groups. The quantitative analyses of the superficial compartment measured an increase in the amount of granulation tissue (32-88% control; 14-41% XCM) from day 4 to day 8. Angiogenesis was first detected at 8 days. At day 29, the amount of connective tissue in all compartments reached values similar to the native tissue at baseline. Conclusions The application of a XCM as a wound dressing on palatal wounds might be beneficial in the early stages of wound healing. Further research with a larger sample size is needed to confirm these results. [ABSTRACT FROM AUTHOR]

Aim To test whether or not the use of a collagen matrix ( VCMX) results in short-term soft tissue volume increase at implant sites non-inferior to an autogenous subepithelial connective tissue graft ( SCTG), and to evaluate safety and tissue integration of VCMX and SCTG. Methods In 20 patients with a volume deficiency at single-tooth implant sites, soft tissue volume augmentation was performed randomly allocating VCMX or SCTG. Soft tissue thickness, patient-reported outcome measures ( PROMs), and safety were assessed up to 90 days ( FU-90). At FU-90 (abutment connection), tissue samples were obtained for histological analysis. Descriptive analysis was computed for both groups. Non-parametric tests were applied to test non-inferiority for the gain in soft tissue thickness at the occlusal site. Results Median soft tissue thickness increased between BL and FU-90 by 1.8 mm (Q1:0.5; Q3:2.0) ( VCMX) ( p = 0.018) and 0.5 mm (−1.0; 2.0) ( SCTG) ( p = 0.395) (occlusal) and by 1.0 mm (0.5; 2.0) ( VCMX) ( p = 0.074) and 1.5 mm (−2.0; 2.0) ( SCTG) ( p = 0.563) (buccal). Non-inferiority with a non-inferiority margin of 1 mm could be demonstrated ( p = 0.020); the difference between the two group medians (1.3 mm) for occlusal sites indicated no relevant, but not significant superiority of VCMX versus SCTG (primary endpoint). Pain medication consumption and pain perceived were non-significantly higher in group SCTG up to day 3. Median physical pain ( OHIP-14) at day 7 was 100% higher for SCTG than for VCMX. The histological analysis revealed well-integrated grafts. Conclusions Soft tissue augmentation at implant sites resulted in a similar or higher soft tissue volume increase after 90 days for VCMX versus SCTG. PROMs did not reveal relevant differences between the two groups. [ABSTRACT FROM AUTHOR]

Purpose This study aims to test whether or not veneering of the submucosal part of zirconia abutments with pink dental ceramic affects radiographic and technical outcomes of implant-supported single crowns (ISSC). Materials and Methods Single tooth implants were randomly restored with either pink-veneered zirconia abutments (test; n = 10) or non-veneered zirconia abutments (control group; n = 10) and all-ceramic crowns. At baseline (crown insertion), and 6- and 12-month radiographic and technical evaluations were performed including standardized x-rays and modified United States Public Health Service criteria (technical). Survival and complication rates were assessed for implants and restorations. Robust linear mixed model analysis was performed to investigate the effect of group and time-point on radiographic outcomes. Results At 1 year, the survival rate for implants was 100% and 95% for ISSC. Most of the implants were placed subcrestally. Therefore, mean marginal bone levels decreased in both groups between implant insertion and baseline ( p < .05), but then remained stable up to 1 year (test: 0.15 mm ± 0.42 mm; control 0.23 mm ± 0.63 mm) ( p > .005). At 6 months, one minor chipping occurred in the test group. At 1 year, three crowns (control) exhibited occlusal roughness. In addition, one abutment fracture occurred (test). The differences between test and control group were not statistically significantly different for any of the evaluated outcome measures ( p > .05). Conclusions Veneering of the submucosal part of zirconia abutments did not affect biological and technical outcomes of ISSCs. Technical complications of the reconstructions, however, were frequent, resulting in a rate of 75% of the crowns being complication free. [ABSTRACT FROM AUTHOR]

Aim To test whether an equine bone substitute block used for guided bone regeneration ( GBR) of peri-implant defects renders different results from bovine block or particulated bone substitutes regarding the dimensions of the augmented ridge and the amount of new bone. Material and methods Mandibular premolars and molars were extracted in eight dogs. After 4 months, four semi-saddle bone defects were created in each mandible and one titanium implant was inserted into every site. Bone augmentation by GBR was attempted using the following randomly assigned modalities: (i) particulated deproteinized bovine bone mineral ( DBBM) + a collagen membrane ( CM), (ii) block DBBM + CM, (iii) equine bone substitute block + CM, and (iv) empty controls. After 4 months, one central and two lateral sections of each site were prepared. Descriptive histological and histomorphometrical assessments were performed evaluating the augmented area ( AA) within the former bone defect, the area of mineralized tissue ( MT), non-mineralized tissue ( NMT), and residual bone substitute ( BS) within AA, the horizontal thicknesses of the augmented region ( HTaugm) and of the mucosa ( HTmucosa). Results At the central sections, AA measured 11.2 ± 3.3 mm2 for the equine block, 9.5 ± 2.6 mm2 for DBBM block, 7.9 ± 4.8 mm2 for particulated DBBM, and 2.4 ± 2.1 mm2 for the empty control. All GBR groups rendered significantly higher values of AA in comparison with control ( P ≤ 0.05). The differences in AA between GBR groups did not reach statistical significance ( P > 0.05). The equine block rendered the highest values in HTaugm, although only the differences between equine block and control as well as equine block and DBBM block were statistically significant ( P ≤ 0.05). With respect to HTmucosa, all GBR groups reached significantly higher values compared to control ( P ≤ 0.05). The equine block revealed the most pronounced signs of graft degradation. Conclusions Guided bone regeneration lead to higher ridge dimensions and thicker covering mucosa than empty controls. The equine block with CM resulted in the most favorable outcomes regarding the maintenance of ridge contour. There were no significant differences regarding amount of new bone between GBR treatments. [ABSTRACT FROM AUTHOR]

Objectives The aim was to test whether or not the marginal bone-level alterations of loaded zirconia implants are similar to the bone-level alterations of a grade 4 titanium one-piece dental implant. Materials and methods In six dogs, all premolars and the first molars were extracted in the mandible. Four months later, three zirconia implants ( BPI, VC, ZD) and a control titanium one-piece ( STM) implant were randomly placed in each hemimandible and left for transmucosal healing (baseline). Six months later, CAD/ CAM crowns were cemented. Sacrifice was scheduled at 6-month postloading. Digital X-rays were taken at implant placement, crowns insertion, and sacrifice. Marginal bone-level alterations were calculated, and intra- and intergroup comparisons performed adjusted by confounding factors. Results Implants were successfully placed. Until crown insertion, two implants were fractured (one VC, one ZD). At sacrifice, 5 more implants were (partly) fractured (one BPI, four ZD), and one lost osseointegration ( VC). No decementation of crowns occurred. All implant systems demonstrated a statistically significant (except VC) loss of marginal bone between baseline and crown insertion ranging from 0.29 mm ( VC; P = 0.116) to 0.80 mm ( ZD; P = 0.013). The estimated marginal bone loss between baseline and 6 months of loading ranged between 0.19 mm ( BPI) and 1.11 mm ( VC), being statistically significant for STM and VC only ( P < 0.05). The changes in marginal bone levels were statistically significantly different between zirconia implants and control implants ( STM vs. BPI P = 0.007; vs. VC P = 0.001; vs. ZD P = 0.011). Conclusions Zirconia implants were more prone to fracture prior to and after loading with implant-supported crowns compared to titanium implants. Individual differences and variability in the extent of the bone-level changes during the 12-month study period were found between the different implant types and materials. [ABSTRACT FROM AUTHOR]

Aim: To compare, clinically and radiographically, short dental implants (6 mm) to long implants (11-15 mm) placed with sinus grafting. Methods: Participants with 5-7 mm of bone height in the posterior maxilla were randomly allocated to receive short implants (GS) or long implants with sinus grafting (GG). Implants were loaded with single crowns 6 months after placement (PR). Patients were re-evaluated 12 months after loading (FU-1). Outcome variables included: Implant survival rate (CSR), marginal bone level alteration (MBL), periodontal probing depth (PPD), bleeding on probing (BoP), plaque control record (PCR) and crown-to-implant ratios (C/I). Statistical analysis was performed using parametric tests. Results: In 97 subjects, 132 implants were re-evaluated at FU-1. The CSR was 100%. The MBL from implant placement (IP) to (PR) was -0.22 ± 0.4 mm for GG and -0.3 ± 0.45 mm for GS (p < 0.001). MBL from IP to FU-1 was -0.37 ± 0.59 mm for GG and -0.22 ± 0.3 mm for GS (p < 0.001). Intergroup comparisons showed non-significant differences for MBL (p > 0.05), PPD (p = 1) and PCR (p = 0.09). BoP was higher in the GS (p = 0.04). The C/I was 0.99 ± 0.17 for GG and 1.86 ± 0.23 for GS (p < 0.001). No correlation was observed between C/I and MBL, (GG: p = 0.13; GS: p = 0.38). Conclusions: Both treatment modalities provided similar outcomes. [ABSTRACT FROM AUTHOR]

Objective: To assess whether or not peri-implant soft tissue dimensions and hard tissue integration of loaded zirconia implants are similar to those of a titanium implant. Materials and methods: In six dogs, two one-piece zirconia implants (VC, ZD), a two-piece zirconia implant (BPI) and a control one-piece titanium implant (STM) were randomly placed. CAD/CAM crowns were cemented at 6 months. Six months later, animals were killed and histomorphometric analyses were performed, including: the level of the mucosal margin, the extent of the peri-implant mucosa, the marginal bone loss and the bone-to-implant contact (BIC). Means of outcomes variables were calculated together with their corresponding 95% confidence intervals. Results: In general, the mucosal margin was located coronally to the implant shoulder. The buccal peri-implant mucosa ranged between 2.64 ± 0.70 mm (VC) and 3.03 ± 1.71 mm (ZD) (for all median comparisons p > 0.05). The relative marginal bone loss ranged between 0.65 ± 0.61 mm (BPI) and 1.73 ± 1.68 mm (ZD) (buccal side), and between 0.55 ± 0.37 mm (VC) and 1.69 ± 1.56 mm (ZD) (lingual side) (p > 0.05). The mean BIC ranged between 78.6% ± 17.3% (ZD) and 87.9% ± 13.6% (STM) without statistically significant differences between the groups (p > 0.05). Conclusions: One- and two-piece zirconia rendered similar peri-implant soft tissue dimensions and osseointegration compared to titanium implants that were placed at 6 months of loading. Zirconia implants, however, exhibited a relatively high fracture rate. [ABSTRACT FROM AUTHOR]

Aim To test whether or not the network structure and the addition of recombinant human platelet-derived growth factor- BB (rh PDGF- BB) to a chemically cross-linked collagen matrix ( CCM)- and a non-cross-linked collagen matrix ( NCCM)-influenced tissue integration, angiogenesis, and matrix degradation. Materials and methods Four treatment modalities were randomly assigned to four unconnected pouches in the back of 50 rats: (i) CCM- S (soaked in saline), (ii) CCM- P (plus rh PDGF- BB), (iii) NCCM- S (soaked in saline), and (iv) NCCM- P (plus rh PDGF- BB). The animals were sacrificed at 2, 4, 8, 16, and 24 weeks. Descriptive histology and histomorphometric assessments were performed thereby evaluating matrix thickness, the number of vessels (angiogenesis), and connective tissue formation. Means and standard deviations were calculated. Robust linear mixed modeling was used to test the effect of group ( NCCM vs CCM), rh PDGF- BB, and time point of sacrifice (2, 4, and 8 weeks). Results The thickness of NCCM groups revealed stability (range 440-570 μm) over 8 weeks, while the matrices were no longer present at 16 and 24 weeks. CCM matrices demonstrated a maximal thickness at 2 weeks (2689 ± 187 μm for CCM- S and 2693 ± 389 μm for CCM- P), a decrease of roughly 40% at 8 weeks, but were still present at 16 and 24 weeks. Vascularization of NCCM gradually increased over time with a peak (mean 17.0; SD 1.7) for NCCM-S and NCCM- P (22.0 ± 34.8) at 8 weeks. Angiogenesis in CCM was significantly more pronounced at early time points with a peak at 2 weeks (29.3 ± 16.8 for CCM- S and 30.3 ± 18.4 for CCM- P). No statistically significant effect of rh PDGF- BB was observed for any of the evaluated parameters (all P > 0.05). Conclusions The compact layer (in NCCM) delayed angiogenesis and connective tissue formation, while the spongeous cross-linked matrix of CCM facilitated early vascularization and demonstrated network presence over a longer time span. [ABSTRACT FROM AUTHOR]

Aim To test whether or not the use of short dental implants (6 mm) results in an implant survival rate similar to long implants (11-15 mm) in combination with sinus grafting. Methods This multicentre study enrolled 101 patients with a posterior maxillary bone height of 5-7 mm. Patients randomly received short implants (6 mm) (group short) or long implants (11-15 mm) with sinus grafting (group graft). Six months later, implants were loaded with single crowns and patients re-examined at 1 year of loading. Outcomes included treatment time, price calculations, safety, patient-reported outcome measures ( OHIP-49 = Oral Health Impact Profile) and implant survival. Statistical analysis was performed using a non-parametric approach. Results In 101 patients, 137 implants were placed. Mean surgical time was 52.6 min. (group short) and 74.6 min. (group graft). Mean costs amounted to 941 EUR (group short) and 1946 EUR (group graft). Mean severity scores between suture removal and baseline revealed a statistically significant decrease for most OHIP dimensions in group graft only. At 1 year, 97 patients with 132 implants were re-examined. The implant survival rate was 100%. Conclusions Both treatment modalities can be considered suitable for implant therapy in the atrophied posterior maxilla. Short implants may be more favourable regarding short-term patient morbidity, treatment time and price. [ABSTRACT FROM AUTHOR]

Dental implants have proven to be a successful treatment option in fully and partially edentulous patients, rendering long‐term functional and esthetic outcomes. Various factors are crucial for predictable long‐term peri‐implant tissue stability, including the biologic width; the papilla height and the mucosal soft‐tissue level; the amounts of soft‐tissue volume and keratinized tissue; and the biotype of the mucosa. The biotype of the mucosa is congenitally set, whereas many other parameters can, to some extent, be influenced by the treatment itself. Clinically, the choice of the dental implant and the position in a vertical and horizontal direction can substantially influence the establishment of the biologic width and subsequently the location of the buccal mucosa and the papilla height. Current treatment concepts predominantly focus on providing optimized peri‐implant soft‐tissue conditions before the start of the prosthetic phase and insertion of the final reconstruction. These include refined surgical techniques and the use of materials from autogenous and xenogenic origins to augment soft‐tissue volume and keratinized tissue around dental implants, thereby mimicking the appearance of natural teeth. [ABSTRACT FROM AUTHOR]

Objective i) To test whether or not pH modifications of a PEG hydrogel matrix influence degradation time and bone regeneration in acute and unprepared (chronic) defects; and ii) to test whether or not the addition of a PEG hydrogel to hydroxyapatite/tricalciumphosphate (HA/TCP) can further enhance bone regeneration compared to HA/TCP alone in acute defects. Materials and methods In 11 mini-pigs, three acute standardized defects and one chronic site were prepared in each hemi-mandible. The following treatment modalities were applied in acute defects: PEG hydrogel regular (PEG 8.7), PEG hydrogel pH-modified plus (PEG 9.0), PEG hydrogel pH-modified minus (PEG 8.4), PEG 8.7 mixed with HA/TCP granules (PEG-HA/TCP), HA/TCP granules (HA/TCP), and empty control (control). In chronic sites, PEG 8.7 and PEG 9.0 were applied. Subsequently primary wound closure was obtained and animals sacrificed at 10 ( n = 6) and 21 days ( n = 5). Descriptive histology and histomorphometric analyses were performed including measurements for newly formed bone, remaining hydrogel, and percent defect fill. Standard descriptive statistics were calculated, and regression analysis used to determine the difference between treatments, taking into account relevant factors and correction for multiple comparisons. Results In acute defects, the amount of newly formed bone increased statistically significantly over time for all treatments. The increase was higher for PEG 8.7 (35.9%) compared with PEG 8.4 and PEG 9.0 and was higher for PEG- HA/ TCP (24.7%) than for HA/ TCP (14.6%). The remaining hydrogel ranged between 7.6 ± 13.3% for PEG 8.4 and 17.7 ± 12.8% for PEG 8.7 at 10 days. At 21 days, no remaining hydrogel was found except for PEG- HA/ TCP (11.5 ± 10.4%). In chronic sites, at 10 days, the remaining hydrogel covered 29.5 ± 10.3% ( PEG 9.0) and 25.6 ± 21.8% ( PEG 8.7) of the area. At 21 days, the amount of hydrogel (29.7 ± 31.7% for PEG 9.0; 1.4 ± 2.5% for PEG 8.7) decreased, while the amount of bone increased to 14.0 ± 16.3% for PEG 9.0 and to 37.9 ± 15.7% for PEG 8.7. Conclusions The PEG hydrogel matrix with a mid-range pH (PEG 8.7) may serve as a matrix for localized bone regeneration with or without the addition of a bone substitute material. This was demonstrated by enhanced bone regeneration in acute and chronic defects compared with control hydrogels and HA/TCP alone. [ABSTRACT FROM AUTHOR]