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Objective: Assess whether horizontal ridge augmentation with guided bone regeneration (GBR) using deproteinized bovine bone mineral (DBBM), autologous bone, and a resorbable collagen membrane supports successful implant placement., Materials and Methods: This open, prospective, single-cohort, multicenter clinical study included patients with ridge defects that required GBR prior to implant insertion. The primary endpoint was radiologically assessed bone gain after 8 months post-GBR, measured at the center of planned implant sites. Secondary endpoints included implant survival and success, marginal bone levels (MBLs), MBL changes, and soft tissue health., Results: Of 45 patients evaluated 8 months post-GBR, nine experienced dehiscence in the first 3 weeks of the healing period. GBR led to radiologically determined mean bone width gain of 4.0 ± 1.5 mm and 4.8 ± 1.7 mm, measured 1 and 3 mm from the top of the crest, respectively, allowing successful implant placement in 44 patients (97.8%). The cumulative implant survival and success rates were 98.9% and 95.5%, respectively. MBLs were stable: -1.18 ± 0.64 mm at definitive prosthesis placement (DPP) and - 1.07 ± 0.74 mm at 1 year. Soft tissue health and esthetics (plaque and bleeding indices, papilla, keratinized mucosa, and pink esthetic score) improved from DPP to 1 year. Patients were highly satisfied with implant function and esthetics, and their oral health-related quality of life improved., Conclusions: GBR using DBBM and a collagen membrane offered a safe and effective treatment option for horizontal ridge augmentation sufficient to support implant-based tooth rehabilitation., Trial Registration: Registered at ClinicalTrials.gov NCT03028922 (registrations sites, as above listed affiliations, first posted January 23, 2017)., (© 2024 The Author(s). Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Objectives: The aim of the present review and meta-analysis was to evaluate the influence of soft tissue thickness on initial bone remodeling after implant installation., Materials and Methods: A literature search was conducted by two independent reviewers on electronic databases up to May 2022. Randomized controlled trials (RCTs) and controlled clinical trials (CCTs) performed on human subjects were included. The risk of bias was evaluated using Cochrane Collaboration's tool. Meta-analysis and Trial Sequential Analysis (TSA) were performed on the selected articles. The primary outcome was marginal bone loss., Results: After screening, 6 studies were included in the final analysis, with a total of 354 implants, and a follow-up from 10 to 14 months. 194 implants were placed in a ≥ 2 mm soft tissue thickness, while 160 had <2 mm soft tissue thickness before implant placement. The included studies had a high level of heterogeneity (I 2  > 50%). The meta-analysis indicated a statistically significant difference between the two groups (0.54; p = .027) and the TSA analysis confirmed the results, despite the limited number of dental implants. Additional analysis showed that age and follow-up parameters were not statistically significant factors influencing the bone loss (p = .22 and p = .16, respectively)., Conclusions: Based on the available RCTS and CCTs, initial soft tissue thickness seems to influence marginal bone loss after a short follow-up period. Based on TSA analysis, further studies are needed to assess the influence of the soft tissue thickness on marginal bone loss. PROSPERO registration number: CRD42021235324., (© 2023 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Objective: To evaluate the potential benefit of the use of a bone substitute material in the reconstructive surgical therapy of peri-implantitis., Methods: In this multicenter randomized clinical trial, 138 patients (147 implants) with peri-implantitis were treated surgically, randomized by coin toss to either a control (access flap surgery) or a test group (reconstructive surgery using bone substitute material). Clinical assessments, including probing pocket depth (PPD), bleeding and suppuration on probing (BOP & SOP) as well as soft tissue recession (REC), were recorded at baseline, 6 and 12 months. Marginal bone levels (MBL), measured on intra-oral radiographs, and patient-reported outcomes (PROs) were recorded at baseline and 12 months. No blinding to group allocation was performed. The primary outcome at 12 months was a composite measure including (i) implant not lost, (ii) absence of BOP/SOP at all aspects, (iii) PPD ≤5 mm at all aspects and (iv) ≤1 mm recession of mucosal margin on the buccal aspect of the implant. Secondary outcomes included (i) changes of MBL, (ii) changes of PPD, BOP%, and buccal KM, (iii) buccal REC and (iv) patient-reported outcomes., Results: During follow-up, four implants (one in the test group, three in the control group) in four patients were removed due to disease progression. At 12 months, a total of 69 implants in the test and 68 implants in the control group were examined. Thus, 16.4% and 13.5% of implants in the test and control group, respectively, met all predefined criteria of the composite outcome. PPD reduction and MBL gain were 3.7 mm and about 1.0 mm in both groups. Reduction in mean BOP% varied between 45% (test) and 50% (control), without significant differences between groups. Buccal REC was less pronounced in the test group (M = 0.7, SD = 0.9 mm) when compared to controls (M = 1.1, SD = 1.5 mm). PROs were favorable in both groups without significant differences. One case of allergic reaction to the antibiotic therapy was recorded. No other adverse events were noted., Conclusions: Surgical therapy of peri-implantitis effectively improved the clinical and radiographic status at 12 months. While the use of a bone substitute material did not improve reductions of PPD and BOP, buccal REC was less pronounced in the test group. Patient satisfaction was high in both groups., (© 2022 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Objectives: To evaluate patients' perceptions regarding implant treatment and maintenance., Material and Methods: A semi-structured questionnaire was developed focusing on 4 main domains: (a) information regarding possible complications received before implant therapy; (b) information received after treatment regarding maintenance; (c) self-performed daily home care; and (d) implant maintenance received at the dental office. Adult patients, restored with implant-supported prosthesis by at least 6 months, were recruited between June 2016 and December 2017., Results: The study population consisted of 522 patients with a mean age of 61 years. The majority of the participants referred to have received information about the need of periodical check-ups (91.6%). However, only 58.9% declared to have been informed about complications and failures before treatment commencement. Even though 91.2% of the participants declared to have received instruction about cleaning measures around implants, less than half of the sample reported to have been asked to try the cleaning tools at the office (40.4%). Even though patients' awareness about implant treatment and maintenance resulted to be low in a consistent part of the sample, patients' satisfaction level about information received regarding implant care was high (Visual Analogue Scale 8.18)., Conclusions: Most patients appeared to be informed about the importance of specific oral hygiene measurements and recall programs. However, an unsatisfactory level of knowledge about implant-related complications was evidenced. Improvements in time and energy employed by dentists and hygienist in communication with patients are needed, in order to enhance health outcomes and compliance both to the treatment and to the maintenance., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: The purpose of this prospective, single-center randomized pilot study was to histologically evaluate and compare vital bone development in premolar and molar-extraction sites grafted with two different bovine-derived xenografts. The secondary outcome of interest was implant survival in the grafted sites., Materials and Methods: Adult patients in need of at least two tooth extractions were enrolled. A paired design was used; each patient received at least one of each type of graft at different sites. Each extraction site was randomized to one of two xenograft treatment groups. A resorbable membrane was always placed, and primary intention soft tissue closure was achieved. Four months later, implants were placed and a trephine drill was used to remove bone cores for histologic and histomorphometric analysis., Results: Sixteen patients with 40 extraction sites were enrolled; 20 sites were grafted with one type of xenograft and 20 with another. Mean patient age was 53.5 years, and 65% of patients were male. Evaluation of bone core samples taken from grafted sites showed no significant difference in the mean value of percentage of new bone formation between the different grafted sites (33.4% and 32.4%, p = .76). Cumulative implant survival was 97.5% at the 24-month follow-up visit., Conclusion: Within the limitations of this pilot study, no statistically significant differences in new bone growth between sites grafted with two different types of xenograft were found. Both graft materials promoted the formation of new bone and provided osseous support for implant placement after socket grafting., (© 2020 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: The aim of the present clinical trial was to analyze, through spectrophotometric digital technology, the influence of the abutment material on the color of the peri-implant soft tissue in patients with thin gingival biotype., Material and Methods: Thirty-seven patients received an endosseous dental implant in the anterior maxilla. At time of each definitive prosthesis delivery, an all-ceramic crown has been tried on gold, titanium and zirconia abutment. Peri-implant soft-tissue color has been measured through a spectrophotometer after the insertion of each single abutment. Also facial peri-implant soft-tissue thickness was measured at the level of the implant neck through a caliper. A specific software has been utilized to identify a standardized tissue area and to collect the data before the statistical analysis in Lab* color space. ΔE parameters of the selected abutments were tested for correlation with mucosal thickness. Pearson correlation test was used., Results: Only 15 patients met the study inclusion criteria on peri-implant soft-tissue thickness. Peri-implant soft-tissue color was different from that around natural teeth, no matter which type of restorative material was selected. Measurements regarding all the abutments were above the critical threshold of ΔE 8.74 for intraoral color distinction by the naked eye. The ΔE mean values of gold and zirconium abutments were similar (11.43 and 11.37, respectively) and significantly lower (P = 0.03 and P = 0.04, respectively) than the titanium abutment (13.55). In patients with a facial soft-tissue thickness ≤2 mm, the ΔE mean value of gold and zirconia abutments was significantly lower than that of titanium abutments (P = 0.03 and P = 0.04, respectively) and much more close to the reference threshold of 8.74., Conclusions: For peri-implant soft tissue of ≤2 mm, gold or zirconia abutments could be selected in anterior areas treatment. Moreover, the thickness of the peri-implant soft tissue seemed to be a crucial factor in the abutment impact on the color of soft tissues with a thickness of ≤2 mm., (© 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: Aim of this study was to verify if the type of implant abutment manufacturing, stock or cad-cam, could influence the maintenance of stable gingival margins around single restorations in anterior areas., Methods: After 16 weeks of healing, implants (Osseospeed, Astra Tech Dental Implant) were positioned. Depending on the different fixture inclination and the thickness of buccal peri-implant soft tissue, abutment selection resulted in four groups: Group 1 (patients with zirconia ZirDesign(®) stock abutments), Group 2 (titanium stock TiDesign(®) abutments), Group 3 (zirconia cad-cam abutments), and Group 4 (titanium cad-cam abutments). The following parameters were assessed: buccal gingival margin modification (BGM). The modification of the implant gingival margin was followed at 1 and 2 years of follow-up. A computerized analysis was performed for measurements. Differences between soft tissue margin at baseline and after 2 years measured the gingival margin recession. A general linear model was used to evaluate each group in relation to gingival recession after two years. Tukey's post hoc test was used to compare the mean REC indexes of each group of abutments., Results: Seventy-two healthy patients (39 males and 33 females; mean age of 46 years) scheduled for single gap rehabilitation in anterior areas were enrolled. A 100% of implant survival rate was observed after 24 months of function. One failure occurred due to fracture of a Zirconia cad-cam abutment. Moreover, two abutment screw unscrewing were observed. Both for zirconia and titanium stock abutments (Group 1 and 2), the mean recession of implant buccal soft tissue was of 0.3 mm (SD of 0.3 and 0.4 mm, respectively). Soft tissue mean recession of zirconia and titanium cad-cam abutments (Group 3 and 4) was of 0.1 and -0.3 mm, respectively (SD of 0.3 and 0.4 mm, respectively). REC values of cad-cam titanium abutments (Group 4) were significantly lower than that of Group 1 (-0.57 mm), Group 2 (-0.61 mm), and Group 3 (-0.40 mm), respectively (Table 4)., Conclusion: In the anterior area, the use of cad-cam abutments is related to a better soft tissue stability. Such a relationship is significant if cad-cam titanium abutments are compared to both titanium and zirconia stock abutments., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To determine the dimensions of the soft tissue cuff present at various aspects of teeth and to compare these dimensions to those of the mucosa surrounding single implants., Material and Methods: Fifty volunteers were recruited that were ≥25 years of age and exhibited no signs of (i) untreated caries; (ii) loss of periodontal tissue support in the incisor, canine, and premolar regions; (iii) systemic or local disease. Furthermore, among the 50 patients recruited (iV), 27 had one single implant in the maxilla with teeth present mesial and/or distal to the implant. Probing pocket depth (PPD) and transmucosal sounding depth (TS) were assessed by five experienced, carefully calibrated examiners and with the use of a periodontal probe at the proximal (mesial, distal) and flat (facial, buccal and palatal/lingual) surfaces of all teeth/implants. The width of the keratinized mucosa (KM) was also determined., Results: It was demonstrated that (i) PPD and TS were greater at proximal than at flat surfaces at both tooth and implant sites. In addition, both PPD and TS were deeper at implant than at tooth sites. The TS values documented that the cuff of healthy soft tissue that surrounded a tooth varied between 2 mm at flat surfaces and 4 mm at proximal surfaces, while at implant sites, the mucosa at proximal as well as flat surfaces was 1-1.5 mm greater., Conclusion: The probing pocket depth (PPD) and the transmucosal sounding depth (TS) values were greater at proximal than at flat, that is, facial/palatal (lingual) surfaces at tooth sites and frequently also at implant sites. Furthermore, the PPD and the TS dimensions were greater at implant than at adjacent tooth sites., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: To address the criticisms raised by Anitua et al. (European Journal of Oral Implantology, 6, 2013, 9-11) to the article "Plasma Rich in Growth Factors (PRGF) in Human Post-Extraction Sockets: an Histological and Histomorphometric Study.", recently published by Farina and colleagues (Clinical Oral Implants Research 2012; doi: 10.1111/clr.12033)., Methods: All the methodological aspects criticized in the letter by Anitua et al. were thoroughly reconsidered and discussed in a structured short communication. When indicated, pertinent, additional material was included to reinforce our considerations., Results: As most clinical studies in implant dentistry, including previous studies evaluating the efficacy/effectiveness of PRGF, the study by Farina et al. has some limitations. However, it is currently the only published controlled trial using quantitative parameters related to PRGF-induced early bone formation., Conclusions: Despite all limitations, the results of the study by Farina et al., which were based on different quantitative parameters (micro-CT scan, immunohistochemical markers of wound healing and bone deposition), indicated a limited effect of PRGF on early bone formation in extraction sockets., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: To evaluate the influence of the configuration of the marginal aspect of implants placed immediately into extraction sockets on peri-implant hard tissue adaptation., Material and Methods: In 6 Labrador dogs, endodontic treatments of the mesial roots of 1 M1 were performed and the distal roots were removed. 2 P2 was extracted as well. Implants were immediately placed in the center of the distal alveoli. Cylindrical straight implants were installed in the right side of the mandible (Control), while, in the left side, implants with a reduced diameter in the coronal portion, yielding an indentation in the surface continuity (Test), were installed. Cover screws were affixed, and the flaps were sutured to allow non-submerged healing. After 4 months of healing, histological slides were obtained for assessments., Results: A buccal resorption of 1.58 ± 1.28 and 1.90 ± 1.93 mm at the control and of 0.26 ± 0.90 and 0.14 ± 0.66 mm at the test sites was observed at the premolar and molar regions, respectively. The buccal coronal level of osseointegration was located apically to the margin of the smooth/rough surface border by 2.40 ± 0.90 and 3.70 ± 0.87 mm at the control sites and 1.19 ± 0.45 and 2.16 ± 0.96 mm at the test sites at the premolar and molar sites, respectively. All differences yielded statistical significance., Conclusions: The use of implants with a reduced diameter in their coronal aspect may contribute to preservation of the buccal bony crest in a more coronal level compared with conventional implants. Thus, the study confirmed the efficacy of the "platform switching" concept., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Purpose: While extensive references are present in the literature dealing with the correlation between subjective and objective evaluation of tooth shade, there is a lack of information on this correlation regarding the soft tissue color. The purpose of this experimental study was to verify whether a correlation between the objective and subjective evaluation exists in analyzing soft tissue color., Material and Methods: A total of 39 patients with at least one implant-supported restoration in the anterior maxilla were included in the study. The shade of the peri-implant mucosa was compared with the shade of the gingiva at the adjacent tooth in a subjective and in an objective manner. The subjective evaluation was performed by five dental professionals (prosthodontist, periodontist, general dentist, dental hygienist, and dental assistant) in a subjective scale (ranging from 1 to 4). The objective evaluation was obtained by means of a spectrophotometer in a CIELAB* Color Scale, and the differences were evaluated through formula ΔE=[(ΔL)²+(Δa)²+(Δb)²]¹/². To correlate the subjective and the objective evaluation, for each arithmetical median value of the subjective evaluation, a mean value of objective evaluation has been calculated, and the Spearman's rank correlation coefficient has been used. The differences have been also analyzed for thin and thick tissue biotypes., Results: The mean ∆E value for the subjective evaluation between peri-implant soft tissue and adjacent tooth gingival tissue was ∆E = 9.74. Also, mean ∆E values of 10.35 and 7.54 have been reported for thin and thick biotypes, respectively. Mean values of ∆E = 6.63, 8.54, and 15.54 were presented by median values of 1 (perfect matching), 2 (good matching), and 3 (clinically distinguishable), respectively. The threshold for the distinction of differences of mucosal color by the human eyes between perfect or good matching and distinguishable values has been calculated in ∆E = 8.74., Conclusions: Within the limitation of this study, a correlation between the subjective and the objective evaluation of the peri-implant soft tissue exists and the threshold for the distinction of mucosal color differences between perfect or good matching and distinguishable subjective values has been calculated in ∆E = 8.74 in the objective evaluation., (© 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objective: The aim of this study was to verify the reliability of a conometric system for a fixed retention of complete prostheses (CPs) on four implants followed for 2 years., Material and Methods: Twenty-five patients received four implants and only one CPs for a total of 100 implants followed. Each prosthesis was supported by four implants. An immediate loading surgical protocol was used. The CPs were provided to be fixed to conometric abutments without prostheses removal by the patients, to test this retention for a fixed instead of a removable rehabilitation. Clinical and radiographical parameters were assessed at the yearly follow-up visit. A follow-up of 2 years was observed for each patient. Moreover, biological and technical complications were recorded. Changes overtime of clinical and radiographic parameters were analyzed as well as the satisfaction degree for each patient., Results: No patient was classified as "dropout." The following results were observed after 2 years of follow-up: all the implants supporting the 25 CPs completed the follow-up examination. No implant, reconstruction, and abutment failure were recorded; therefore, the prosthetic survival was 100% for all the abutments and restorations. No significant differences in biological indexes were observed when compared with the baseline. No significant change of the mean marginal bone level (MBL) was found between the baseline and the last follow-up. No loss of retention was recorded for the CPs. No technical complications referred to abutments and frameworks were observed: a prosthetic survival rate of 100% can be recorded. Mucositis was recorded for two implants and successfully treated with interceptive supportive therapy. No significant differences (P < 0.05) were found between plaque index and MBi parameters at baseline and after 2 years of function. Similar results were recorded for the mean probing pocket depth Index at baseline (1.2 mm with SD of 0.3 mm) and after 2 years of function (1.2 mm with SD of 0.2 mm)., Conclusions: The present implant-supported conometric retention system can be used to give a fixed retention to a CPs supported by four implants immediately loaded. Furthermore, costs reduction and simplified treatment procedures were provided by such a clinical approach., (© 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.)

Objectives: To evaluate the influence on osseointegration of Deproteinized bovine bone mineral (DBBM) particles used to fill defects of at least 1 mm around implants having no primary contact with bone., Material and Methods: Premolars and first molars were extracted bilaterally from the mandible of six Labrador dogs. After 3 months of healing, mucoperiosteal full-thickness flaps were elevated, and one recipient site was prepared in the molar region of each hemi-mandible to place implants. These were installed with a deliberate circumferential and periapical space to the bone walls of 1.2 mm. All implants were stabilized with passive fixation plates to maintain the implants in situ and without any contact with the implant bed. The control sites were left to be filled with coagulum, while at the test sites, the residual gap was filled with DBBM. After 3 months of submerged healing, the animals were sacrificed. Ground sections were prepared and analyzed histomorphometrically., Results: Mineralized bone-to-implant contact was 4.0% and 3.9% for control and test sites, respectively. The width of the residual defects was 0.48 mm and 0.88 mm at the control and test sites, respectively. The percentage of implant surface covered by a layer of dense connective tissue of 0.12 mm of width on average was 84.9% and 88.5% at the control and test sites, respectively., Conclusion: A minor and not predictable degree of contact or distance osteogenesis was obtained on the implant surface when primary contact of the implant surface with the implant bed had deliberately been avoided. DBBM grafting of the artificial gap did not favor osseointegration. Neither did it enhance the ability to bridge the gap with newly formed bone in an artificial defect wider than 1 mm., (© 2013 John Wiley & Sons A/S. Published by Blackwell Publishing Ltd.)

Objectives: To determine whether and to what extent the additional application of plasma rich in growth factors (PRGF) to an extraction socket may influence the early bone deposition, as assessed by micro-computed tomography (micro-CT) scan as well as histomorphometric markers., Material and Methods: Twenty-eight patients (age range: 34-74 years) contributing 36 extraction sockets were included in the study. Sockets were either treated with PRGF (PRGF group; 18 sites in 11 patients) or left to spontaneous healing (control group; 18 sites in 17 patients). Radiographic and histomorphometric analysis was performed on bone cores trephined from each healing socket after 4-6 (T1) or 7-10 (T2) weeks of healing., Results: Patients treated with PRGF application showed (i) similar bone volume and tissue mineral content, (ii) a trend, although not statistically significant, toward a greater number of CD68+ cells (at T1 and T2) and vVW+ cells (at T1), and (iii) a similar OCN staining score throughout the study, when compared with control group., Conclusions: Plasma rich in growth factors-treated group did not show any enhancement in early (4 and 8 weeks) bone deposition compared with control group., (© 2012 John Wiley & Sons A/S.)

Background: The composition of the fully healed edentulous ridge of the posterior maxilla was recently examined and was found to contain about 50% mineralized bone and 16% bone marrow., Aim: The objective was to examine the composition of the tissue of the fully healed ridge in different portions of the maxilla and the mandible in partially dentate subjects., Material and Methods: Eighty-seven healthy subjects were included. A trephine drill was used to harvest hard tissue specimens. The biopsies were decalcified, embedded in paraffin, sectioned, stained, and examined using a point-counting procedure., Results: The marginal portion of the jaws almost consistently contained a cortical cap that was significantly wider in the mandible than in the maxilla and twice as wide in the anterior as in the posterior segments of the mandible. Lamellar bone and bone marrow were the dominating tissue elements. Lamellar bone occupied about 63% of the tissue in the mandible and 46% in the maxilla. The maxilla contained about 23% bone marrow as compared to 16% in the mandible. In the mandible, 70% (anterior) and 57% (posterior) were made up of lamellar bone. In the maxilla, the proportion of lamellar bone in the anterior and posterior segments was similar (about 45%). Bone marrow occupied close to 40% of the anterior maxilla, while in the posterior maxilla and the anterior and posterior mandible marrow comprised between 13 and 18%., Conclusion: Marked differences existed with respect to tissue composition of the edentulous ridge between the maxilla and the mandible. The cortical crest was wider in the mandible than in the maxilla, and widest in the symphysis region of the mandible. The proportion of bone marrow was greater in the maxilla than in the mandible. The maxillary front tooth region was poor in lamellar bone but rich in bone marrow, while the anterior mandible contained large amounts of mineralized bone but small amounts of bone marrow., (© 2012 John Wiley & Sons A/S.)

Aim: To evaluate the influence of implant positioning into extraction sockets on bone formation at buccal alveolar dehiscence defects., Material and Methods: In six Labrador dogs the pulp tissue of the mesial roots of (4) P(4) was removed and the root canals were filled. Flaps were elevated bilaterally, the premolars hemi-sectioned and the distal roots removed. The implants were placed in contact with either the buccal (test site) or with the lingual (control site) bony wall of the extraction sockets. Healing abutments were affixed and triangular buccal bony dehiscence defects, about 2.7 mm deep and 3.5 mm wide, were then prepared. No regenerative procedures were done and a non-submerged healing was allowed. After 4 months of healing, block sections of the implant sites were obtained for histological processing and peri-implant tissue assessment., Results: After 4 months of healing, the bony crest and the coronal border of osseointegration at the test sites were located 1.71 ± 1.20 and 2.50 ± 1.21 mm apically to the implant shoulder, respectively. At the control sites, the corresponding values were 0.68 ± 0.63 and 1.69 ± 0.99 mm, respectively. The differences between test and control reached statistical significance (P < 0.05). Residual marginal bone defects were found both at the test and control sites. A statistically significant difference between test and control sites was only found at the lingual aspects (depth 2.09 ± 1.01 and 1.01 ± 0.48 mm, respectively). Similar heights of the buccal biological width were observed at both sites (about 5.1 mm)., Conclusions: The placement of implants in a lingual position of the extraction sockets allowed a higher degree of bone formation at buccal alveolar dehiscence defects compared with a buccal positioning., (© 2012 John Wiley & Sons A/S.)

Objective: The aim of this cross-sectional study was to determine the clinical outcome and patient satisfaction in subjects treated with mandibular overdentures supported by two implants., Material and Methods: One hundred and fifty-nine patients, who received restorative therapy in the edentulous mandible consisting of a bar-retained overdenture supported by two osseointegrated implants in a private clinic in Italy, were recalled for a clinical and radiographic examination. One hundred and forty-one subjects with 280 implants attended the examination. The average follow-up time was 3.9 years. The radiographic examination included assessments of the distance between the implant margin and the most coronal position of bone-to-implant contact at the mesial and distal aspects of each implant. A questionnaire regarding comfort, satisfaction with the treatment, aesthetics, speaking capacity and efficiency in chewing was obtained from each subject. Biological and technical complications were recorded and the number of visits due to complications between the delivery of the prostheses and the re-examination was determined., Results: The results from the examination revealed that the number of lost implants was small and the average marginal bone level around the implants was 0.67 mm apical of the implant margin. The most frequently observed complication was hyperplasia of the mucosal tissue under the bar construction. Few patients experienced loosening of retention. The vast majority of patients reported to be satisfied in relation to the restorative therapy from both functional and aesthetic points of view., Conclusion: Patients with edentulous mandibles may be successfully rehabilitated by means of two implants supporting a bar-retained overdenture., (© 2011 John Wiley & Sons A/S.)

Aim: To evaluate the healing at implants with a moderately rough surface placed and stabilized in recipient sites of dimensions deeper and larger than that of the implants to avoid any contact between parent bone and the implant., Material & Methods: In six Labrador dogs, premolars and first molars were extracted bilaterally in the mandible. After 3 months of healing, mucoperiosteal full-thickness flaps were elevated and the premolar area of the alveolar bony crest was selected. Three recipient sites were prepared to place three implants. One implant was used as control. The other two were placed in recipient sites which left a circumferentially and periapical prepared defect of 0.7 mm (small) and 1.2 mm (large), respectively. All implants were stabilized with passive fixation plates to maintain the implants stable and without any contact with the implant bed. After 3 months of submerged healing, the animals were sacrificed. Ground sections were prepared and analyzed histomorphometrically., Results: The BIC% was 5.3% and 0.3% for implants placed in small and large defect sites, respectively, whereas it was 46.1% for control implants. The differences were statistically significant. The width of the residual defects was 0.4 and 0.5 mm at the small and large defects, respectively. An approximately 0.09 mm layer of dense connective tissue (DCT) rich in fibers and fibroblast-like cells was observed adherent to the implant surfaces. The percentage of implant surface covered by DCT was 92.8% and 95.6% at the small and large defects, respectively., Conclusion: Osseointegration was observed at the test sites, and the dimensions of the defects influenced the outcomes. However, the degree of osseointegration at both small and large defects was very low compared with the control sites., (© 2012 John Wiley & Sons A/S.)

Aim: To evaluate the effect of implant length (6 mm vs.11 mm) on osseointegration (bone-to-implant contact) of implants installed into sockets immediately after tooth extraction., Material and Methods: In six Labrador dogs, the pulp tissue of the mesial roots of (3) P(3) was removed and the root canals were filled. Flaps were elevated bilaterally, the premolars hemi-sectioned and the distal roots removed. Recipient sites were prepared in the distal alveolus and a 6 mm or an 11 mm long implant was installed at the test and control sites, respectively. Non-submerged healing was allowed. After 4 months of healing, block sections of the implant sites were obtained for histological processing and peri-implant tissue assessment., Results: No statistically significant differences were found between test and control sites both for hard and soft tissue parameters. The bone-to-implant contact evaluated at the apical region of the implants was similar as well. Although not statistically significant, the location of the top of the bony crest at the buccal aspect was more apical in relation to the implant shoulder at the test compared with the control sites (2.0 ± 1.4 and 1.2 ± 1.1 mm, respectively)., Conclusions: Shorter implants (6 mm) present with equal osseointegration than do longer implants (11 mm)., (© 2012 John Wiley & Sons A/S.)

Purpose: The aim of this clinical research on implant-supported restorations is to analyze, through spectrophotometric digital technology, the influence of the abutment material on the color of the peri-implant soft tissue., Material and Methods: Twenty patients received an endosseous dental implant in the anterior maxilla. At the time of each definitive prosthesis delivery, an all-ceramic crown has been tried on gold, titanium and zirconia abutment. After the insertion of each single abutment, the peri-implant soft tissue color has been measured through a spectrophotometer. Also, the thickness of the facial peri-implant soft tissue was measured at the level of the implant neck through a caliper. A specific software has been utilized to identify a specific tissue area and to collect the data before the statistical analysis in Lab* color space. The normality of the quantitative variables was verified by means of the Shapiro-Wilk test. Simple linear correlation between quantitative variables was evaluated by using Pearson's coefficient. The results on the performance of the abutment materials with regard to the color measurements and the overall measurement ΔE were described by computing the least-square means. The significance of differences among types of abutment was verified by means of the Scheffe test for multiple comparisons., Results: For all the abutments used, the color of the peri-implant soft tissue appeared to be significantly different from the one of the contra-lateral tooth (ΔE>8.5). Significantly higher (P<0.05) difference were present with the use of titanium abutments (11 ± 0.4) when compared with the results of gold (8.9 ± 0.4) and zirconia (8.5 ± 0.4) abutments. No correlation has been demonstrated between soft tissue thickness and degree of color difference (P>0.25)., Conclusions: Within the limitation of the present study, the peri-implant soft tissue color appears to be different from the soft tissue color around natural teeth, no matter which type of restorative material is selected. When titanium abutment was selected, significantly higher differences were present than those obtained with gold or zirconia abutments. The thickness of the peri-implant soft tissue did not appear to be a crucial factor in the abutment impact on the soft tissue color., (© 2010 John Wiley & Sons A/S.)

Aim: To compare the remodeling of the alveolar process at implants installed immediately into extraction sockets by applying a flap or a "flapless" surgical approach in a dog model., Material and Methods: Implants were installed immediately into the distal alveoli of the second mandibular premolars of six Labrador dogs. In one side of the mandible, a full-thickness mucoperiosteal flap was elevated (control site), while contra-laterally, the mucosa was gently dislocated, but not elevated (test site) to disclose the alveolar crest. After 4 months of healing, the animals were sacrificed, ground sections were obtained and a histomorphometric analysis was performed., Results: After 4 months of healing, all implants were integrated (n=6). Both at the test and at the control sites, bone resorption occurred with similar outcomes. The buccal bony crest resorption was 1.7 and 1.5 mm at the control and the test sites, respectively., Conclusions: "Flapless" implant placement into extraction sockets did not result in the prevention of alveolar bone resorption and did not affect the dimensional changes of the alveolar process following tooth extraction when compared with the usual placement of implants raising mucoperiosteal flaps., (© 2010 John Wiley & Sons A/S.)

Objectives: To evaluate the influence of implant size and configuration on osseointegration in implants immediately placed into extraction sockets., Material and Methods: Implants were installed immediately into extraction sockets in the mandibles of six Labrador dogs. In the control sites, cylindrical transmucosal implants (3.3 mm diameter) were installed, while in the test sites, larger and conical (root formed, 5 mm diameter) implants were installed. After 4 months of healing, the resorptive patterns of the alveolar crest were evaluated histomorphometrically., Results: With one exception, all implants were integrated in mineralized bone, mainly composed of mature lamellar bone. The alveolar crest underwent resorption at the control as well as at the test implants. This resorption was more pronounced at the buccal aspects and significantly greater at the test (2.7+/-0.4 mm) than at the control implants (1.5+/-0.6 mm). However, the control implants were associated with residual defects that were deeper at the lingual than at the buccal aspects, while these defects were virtually absent at test implants., Conclusions: The installment of root formed wide implants immediately into extraction sockets will not prevent the resorption of the alveolar crest. In contrast, this resorption is more marked both at the buccal and lingual aspects of root formed wide than at standard cylindrical implants.

Background: Implant single-tooth replacement with a natural appearance is a challenging and demanding procedure. The aim of this prospective study was to identify the factors affecting the presence of an inter-proximal papilla between a tooth and an implant., Methods: Forty-six patients with a total of 46 teeth scheduled for tooth extraction and immediate implant placement into fresh sockets were included in the study. Immediate implants were positioned after teeth removal. After 4 months of healing, the implants were restored with single crown fixed prostheses. The following parameters were assessed: (1) presence/absence of the inter-proximal papilla, (2) gingival index, (3) inter-implant-tooth distance (ITD) and (4) distance from the base of the contact point to the inter-dental bone (CPB). A computerized analysis was performed to determine ITD and CPB values after converting perioapical radiographs to digitalized images. Statistical analyses were performed to determine the effect of ITD and CPB on the presence or absence of the inter-proximal papilla., Results: All the implants were restored, so that a 100% of implant survival rate was observed after 12 months of function. Mean values were recorded for ITD and CPB parameters, respectively. When ITD was 3-4 mm, and CPB was 3-5 mm, the inter-proximal papilla was significantly present (P<0.05)., Conclusions: The recommended inter-proximal space dimensions are 3-4 mm between an implant and the adjacent tooth, and 3-5 mm between the base of the CPB. The interaction between the surgical and prosthetic plans represents the key factor to optimize the edentulous site for predictable anterior single-implant esthetics.