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Purpose: To histometrically compare the osseointegration and crestal bone healing of a novel tapered, self-cutting tissue-level test implant with a standard tissue-level control implant in a submerged healing regimen., Materials and Methods: In a mandibular minipig model, implants were inserted and evaluated histometrically after a healing period of 3, 6, and 12 weeks. The primary outcome was the evaluation of bone-to-implant contact (BIC) and secondary outcomes were primary stability as per insertion torque and first BIC (fBIC). Outcomes for the test and control implants were compared using Wilcoxon signed-rank tests and mixed linear regression models., Results: Insertion torque values were significantly higher for the test (50.0 ± 26.4 Ncm) compared to the control implants (35.2 ± 19.7 Ncm, p = .0071). BIC values of test implants were non-inferior to those of control implants over the investigated study period. After 12 weeks, the corresponding values measured were 81.62 ± 11.12% and 90.41 ± 4.81% (p = .1763) for test and control implants, respectively. Similarly, no statistical difference was found for fBIC values, except for the 12 weeks outcome that showed statistically lower values for the test (-675.58 ± 590.88 μm) compared to control implants (-182.75 ± 197.40 μm, p = .0068)., Conclusions: Novel self-cutting tissue-level implants demonstrated noninferior osseointegration and crestal bone height maintenance to the tissue-level implants. Histometric outcomes between both implants demonstrated test implants were statistically noninferior to control implants, despite substantial differences in the bone engagement mechanism and resulting differences in insertion torque and qualitative bone healing patterns., (© 2024 The Author(s). Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Introduction: To present the 3-year clinical, radiographic, and aesthetic outcomes in patients with congenitally missing lateral incisors rehabilitated with two narrow-diameter implants (NDIs)., Methods: The original population consisted of 100 patients rehabilitated with a cement-retained bi-layered zirconia single-unit crown supported by either a Ø2.9 mm (Test) or a Ø3.3 mm (Control) NDI (n = 50). At the 1- and 3-year follow-up (T2, T3), implant survival rate, crestal bone level (CBL) changes, biological, and technical complications were recorded, while the assessment of the aesthetic outcomes was performed using the Copenhagen Index Score., Results: Seventy-four patients Ø2.9 mm (n = 39) or Ø3.3 mm (n = 35) reached T3, as 24 patients were lost to follow-up and 1 implant (Ø3.3 mm) was removed. Throughout the observation period, minimal CBL changes (i.e., <1 mm) were detected between groups. Despite the positive aesthetic scores recorded (i.e., 1-2), at T3 20% of patients rehabilitated with a Ø3.3 mm versus 2.6% of patients Ø2.9 mm displayed an alveolar process deficiency (Score 3). No additional technical and/or mechanical complications were recorded between T2 and T3. Tooth vitality was maintained in all neighboring teeth. Peri-implant probing depths and plaque scores remained low in both groups (p > 0.05)., Conclusion: The use of 2.9 or 3.3 diameter implants showed comparable favorable mid-term results in terms of survival rate, CBL, and aesthetic outcomes. Hence, clinicians should rely on the use of such NDIs when replacing maxillary lateral incisors., (© 2024 The Authors. Clinical Implant Dentistry and Related Research published by Wiley Periodicals LLC.)

Objectives: Coenzyme Q10 (CoQ10) or ubiquinone is one of a cell's most important electron carriers during oxidative phosphorylation and many other cellular processes. As a strong anti-oxidant with further anti-inflammatory effects CoQ10 is of potential therapeutical value. The aim of this randomized controlled clinical trial was to investigate the effect of topical CoQ10 on early wound healing after recession coverage surgery using the modified coronally advanced tunnel (MCAT) and palatal connective tissue graft (CTG)., Materials and Methods: Thirty patients with buccal gingival recessions were evaluated after being randomly allocated to: 1) MCAT and CTG with topical application of a coenzyme Q10 spray for 21 days or 2) MCAT and CTG with placebo spray. Wound healing was evaluated by the early wound healing index (EHI). Patient-reported pain was analyzed by a 100-mm visual analogue scale (VAS) at day 2, 7, 14 and 21 post-surgically. Mean recession coverage, gain of keratinized tissue and esthetic outcomes were assessed at 6 months., Results: EHI and pain scores showed no significant differences. Time to recovery defined as VAS<10 mm was shorter in the test group. Mean root coverage after 6 months was 84.62 ± 26.57% and 72.19 ± 26.30% for test and placebo, p=0.052. Complete root coverage was obtained in 9 (60%) test and in 2 (13.3%) placebo patients. Increase in keratinized tissue width and esthetical outcomes were similar for both groups., Conclusion: CoQ10 had no significant effect on early wound healing and on mean root coverage after 6 months., Clinical Relevance: Early wound healing: in young healthy patients with no inflammatory oral conditions topical CoQ10 does not improve early healing., (© 2024. The Author(s).)

Following a comprehensive patient examination, including the assessment of periodontal and peri-implant diseases as well as considering the patient's needs, a pretherapeutic prognosis for each tooth and implant is given. Teeth and implants with a secure pretherapeutic prognosis require simple procedures and may be regarded as secure abutments for function and with a doubtful pretherapeutic prognosis usually need a comprehensive therapy. Such teeth and implants must be brought into the category with a secure prognosis by means of additional therapy such as endodontic, restorative, and surgical procedures. Teeth and implants with a hopeless pretherapeutic prognosis should be extracted/explanted during the initial phase of cause-related therapy (i.e., infection control). For example, teeth with vertical root fracture or unrestorable caries and implants with mobility or unrestorable malposition fall into the category of hopeless units. The primary goal of periodontal and peri-implant therapy should be to arrest disease progression. The latest consensus statement highlights that periodontitis can be successfully controlled and treated teeth can be retained for life. Nevertheless, for patients with uncontrolled contributing factors, the endpoints might not always be achievable, and low disease activity may be an acceptable therapeutic goal. Similarly, the management of peri-implantitis frequently requires surgical intervention following nonsurgical therapy due to incomplete treatment outcomes. Different surgical modalities can be effective and lead to significant improvement; however, achieving complete resolution of peri-implantitis is challenging, not always predictable, and can depend on multiple baseline factors. Therefore, this review aims at summarising available evidence on the rationale for incorporating systemic, lifestyle-related, clinical, and radiographic prognostic factors into treatment planning of patients diagnosed with periodontal and peri-implant diseases., (Periodontology 2000© 2024 The Author(s). Periodontology 2000 published by John Wiley & Sons Ltd.)

Aims: To histologically compare osseointegration and crestal bone healing between newly introduced tapered, self-cutting bone-level test implants and tapered bone-level control implants in sites with fully healed sites., Methods: Sixty-six implants (33 test, 33 control) were placed 1 mm subcrestally in a minipig model and underwent qualitative histologic and quantitative histometric analyses after 3, 6 and 12 weeks of submerged healing. The primary and secondary outcomes were the bone-to-implant contact (BIC) and first bone-to-implant contact (fBIC). Outcomes between the test and control implants were statistically compared., Results: The BIC values of the test implants were comparable and non-inferior over the time points studied, except for the 12 weeks time point which showed statistically significantly higher BIC values of the test (88.07 ± 5.35%) compared to the control implants (80.88 ± 7.51%) (p = .010). Similarly comparable and non-inferior were the fBIC values, except for the 6-week outcome, which showed statistically higher values for the test (-546.5 ± 450.80 μm) compared to the control implants (-75.7 ± 100.59 μm). fBIC results for the test implants were qualitatively more stable and consistent between test time points., Conclusion: Novel self-cutting bone-level test implants demonstrated superior osseointegration and similar bone levels compared to conventional bone-level implants after a healing period of 12 weeks in healed ridges., (© 2024 The Authors. Journal of Periodontal Research published by John Wiley & Sons Ltd.)

The aim of this study was to retrospectively analyze the implant failure rate, not due to peri-implantitis, in periodontally compromised patients rehabilitated with at least one dental implant placed in a specialist university setting over the last 18 years. Records of patients receiving dental implants at the Department of Periodontology, University of Bern, Switzerland, between 2005 and 2022 were analyzed. Data on 1821 patients with 2639 implants were retrieved. Fifty-nine patients experienced implant loss (rate at patient level: 3.2%) out of which 2.1% were early and 1.1% late implant losses, respectively. The majority of the 59 patients were males (68%) and 27.1% were smokers. Eight mm implants were lost with the highest rate (42.4%) followed by 10 mm implants (31.8%). The rate of lost maxillary implants was more than twice as high compared with that of mandibular implants (69.7 vs. 30.3%). Within the study limitations, the implant failure rate in this cohort of patients enrolled in regular supportive periodontal and peri-implant care, was low., Competing Interests: The authors declare no potential conflict of interests with respect to this study., (Copyright 2024 SWISS DENTAL JOURNAL SSO – Science and Clinical Topics. License: This work is licensed under a Creative Commons Attribution 4.0 International License.)

Objective: To evaluate the potential of a novel synthetic carbonate apatite bone substitute (CO 3 Ap-BS) on periodontal regeneration., Background: The use of various synthetic bone substitutes as a monotherapy for periodontal regeneration mainly results in a reparative healing pattern. Since xenografts or allografts are not always accepted by patients for various reasons, a synthetic alternative would be desirable., Methods: Acute-type 3-wall intrabony defects were surgically created in 4 female beagle dogs. Defects were randomly allocated and filled with CO 3 Ap-BS (test) and deproteinized bovine bone mineral (DBBM) or left empty (control). After 8 weeks, the retrieved specimens were scanned by micro-CT, and the percentages of new bone, bone substitute, and soft tissues were evaluated. Thereafter, the tissues were histologically and histometrically analyzed., Results: Healing was uneventful in all animals, and defects were present without any signs of adverse events. Formation of periodontal ligament and cementum occurred to varying extent in all groups without statistically significant differences between the groups. Residues of both bone substitutes were still present and showed integration into new bone. Histometry and micro-CT revealed that the total mineralized area or volume was higher with the use of CO 3 Ap-BS compared to control (66.06 ± 9.34%, 36.11 ± 6.40%; p = .014, or 69.74 ± 2.95%, 42.68 ± 8.68%; p = .014). The percentage of bone substitute surface covered by new bone was higher for CO 3 Ap-BS (47.22 ± 3.96%) than for DBBM (16.69 ± 5.66, p = .114)., Conclusions: CO 3 Ap-BS and DBBM demonstrated similar effects on periodontal regeneration. However, away from the root surface, more new bone, total mineralized area/volume, and higher osteoconductivity were observed for the CO 3 Ap-BS group compared to the DBBM group. These findings point to the potential of CO 3 Ap-BS for periodontal and bone regeneration., (© 2023 The Authors. Journal of Periodontal Research published by John Wiley & Sons Ltd.)

Background: The aim of this study was to compare the clinical efficacy and the patient perception of subgingival debridement with either guided biofilm management (GBM) or conventional scaling and root planing (SRP) during supportive periodontal care (SPC)., Methods: Forty-one patients in SPC were randomly assigned to either treatment with GBM or SRP every 6 months. The primary outcome was the percentage of bleeding on probing (BoP) at 1 year. Moreover, pocket probing depths (PPD), recession, and furcation involvements were also measured. Full-mouth and specific site analyzes were performed at baseline, 6 and 12 months of SPC. Patient comfort was evaluated using a visual analogue scale (VAS) at 12 months., Results: At 1 year, mean BoP percentage decreased from 12.2% to 9.0% (p = 0.191) and from 14.7% to 7.9% (p = 0.004) for the GBM and SRP groups, respectively. Furcation involved multirooted teeth but no through-and-through lesions were significantly fewer in the GBM than in the SRP group after 12 months (p = 0.015). The remaining parameters showed slight improvement in both groups without any statistically significant differences between the two groups after 1 year. Pain evaluation as patient reported outcome measures (pain evaluation) was in favor (p = 0.347) of the SRP group, while overall satisfaction was similar for both groups. Treatment time was not statistically significantly different between the two groups (p = 0.188)., Conclusion: In well-maintained SPC patients, SRP protocols resulted in significant clinical improvements in terms of BoP; however, for the other clinical improvements, similar efficacy for both GBM and SRP was observed., (© 2024 The Authors. Journal of Periodontology published by Wiley Periodicals LLC on behalf of American Academy of Periodontology.)

Aim: To investigate the healing after heterotopic mucosa transpositioning at dental implants and teeth., Materials and Methods: One hemimandible per dog (n = 4) was allocated to receive 3 implants (test), whereby 3 premolars on the contralateral side served as controls. After osseointegration, a Z-plasty was performed on the buccal aspect of the test and control sites to heterotopically move the zone of keratinized tissue (KT) into a region with non-keratinized tissue (nKT) and vice versa. Clinical measurements were performed before (T0) and at 12 weeks following heterotopic transposition (T1). Thereafter, specimens were processed for histological analysis., Results: Clinical measurements revealed that at T1, a band of KT was reestablished at teeth (mean: 2.944 ± 1.866 mm), whereas at implants, the transpositioned nKT resulted in a mucosa without any signs of keratinization (mean: 0 mm; p < .0001). At implant sites, the probing attachment level loss was more pronounced compared to tooth sites (-1.667 ± 1.195 mm and -1.028 ± 0.878 mm, respectively; p = .0076). Histologically, the transpositioned nKT, was accompanied by the formation of KT at the tooth but not at implant sites. The supracrestal soft tissues were statistically significantly higher at tooth compared to implant sites (2.978 ± 0.483 mm and 2.497 ± 0.455 mm, p = .0083). The transpositioned KT remained mostly unaltered in its morphological characteristics., Conclusions: The findings of this study indicate that: (a) transpositioned KT may retain its morphological characteristics; and (b) transpositioned nKM was accompanied by the formation of KT at the tooth but not at implant sites., (© 2023 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Objectives: To investigate the influence of instrumentation angle during low-abrasive air polishing (LAA) on the oral gingiva using an ex vivo porcine model., Material and Methods: Six tissue samples from each of 14 porcine mandibles were randomly selected and instrumented. Two different LAA powders (glycine 25 μm, tagatose 15 μm) were investigated. An application angle of either 30-60° or 90° was selected. Gingival specimens from different mandibles served as untreated references. Gingival biopsies were examined by scanning electron microscopy and paraffin histology for tissue destruction using a five-level scale., Results: LAA caused significantly less tissue damage at a 90° angle than at a 30-60° angle. This effect was seen in both the glycine-based powder arms (p = 0.002, p = 0.046) and the tagatose-based powder arms (p = 0.003, p = 0.011). However, at identical working angles, the two powders did not show significant differences in terms of gingival erosion (p = 0.79 and p = 0.57; p = 0.91 and p = 0.78, respectively)., Conclusions: LAA may cause less tissue damage at an application angle of 90°. Consequently, it seems advisable to air-polish the soft tissue as perpendicularly as possible. Additionally, glycine and tagatose LAA powders do not seem to differ in concern of soft tissue damage., Clinical Relevance: Within the limitations of this ex vivo animal model, this study argues for an application that is as close as possible to the 90° angle intending to minimize soft tissue damage. Manufacturer specifications, however, mainly request applications deviating from the right angle. In order to work in interdental areas using LAA safely, the use of subgingival nozzles might be considered., (© 2023. The Author(s).)

Objectives: To test the reliability of full zirconia implant-supported fixed dental prostheses with cantilever extension (FDPCs) after at least 1 year of function., Materials and Methods: Thirty-five patients in need of implant-supported single unit crowns (SUC) and FDPCs in posterior areas were enrolled. After implant placement, patients were rehabilitated with screw-retained full-zirconia FDPCs. Implant survival rate, pocket probing depth (PPD), presence/absence of bleeding on probing (BoP), and presence/absence of mechanical/technical complications were recorded. Mesial and distal radiographic marginal bone levels (mBLs) from baseline (i.e., recall appointment 3-6 months after implant loading [T0]) to the follow-up examination (i.e., latest recall appointment after at least 12 months after T0 [T1]), were calculated., Results: Thirty patients with 34 FDPCs (31 SUCs and 3 FDPs) supported by 37 implants were available for analysis after a mean loading time of 2.6 ± 1.5 years (range: 13-87 months). No implants were lost. MBLs and mean PPD values did not change statistically significantly from T0 to T1 from 0.92 mm ± 0.42 to 0.96 mm ± 0.38 (95% CI: -0.07/0.17; p = .418) and from 2.99 mm ± 0.70 to 3.27 mm ± 0.71 (95% CI: -0.11/0.68; p = .25) respectively. Peri-implant mucositis was diagnosed in 22 cases. Screw-loosening and zirconia chipping occurred 1× in 4 patients., Conclusion: Within the limitations of the present proof-of-principle study, the use of full-zirconia FDPCs in posterior areas seems a valid and safe short-term treatment option., (© 2023 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Purpose: To longitudinally assess the prevalence of peri-implant health, peri-implant mucositis and peri-implantitis in a cohort of patients with and without history of periodontitis over a 20-year period., Materials and Methods: Eighty-four patients who attended a specialist private periodontal practice were evaluated prospectively 10 and 20 years after prosthesis delivery. Following successful completion of periodontal/implant therapy, patients (172 implants) were enrolled on an individualised supportive periodontal care programme. Clinical and radiographic parameters were collected to assess the prevalence of peri-implant health and diseases. Prevalence of peri-implantitis and peri-implant mucositis was calculated based on the case definition set out in 2018. A multilevel logistic regression analysis was conducted to assess potential risk or protective factors., Results: The analysis was performed on 22 periodontally healthy and 62 periodontally compromised patients rehabilitated with 39 and 130 implants, respectively. The 10-year prevalence of peri-implant health, peri-implant mucositis and peri-implantitis was 21.4%, 67.9% and 10.6%, respectively, whereas the 20-year prevalence was 29.8%, 47.6% and 33.3%, respectively. Non-compliant periodontally compromised patients showed a statistically significantly increased risk at 20 years of both peri-implant mucositis (odds ratio 11.1; 95% confidence interval 1.8-68.6) and peri-implantitis (bone loss and probing depth) (odds ratio 14.3; 95% confidence interval 1.8-32.9). High full-mouth plaque and bleeding scores were associated with higher odds of both peri-implant mucositis and peri-implantitis., Conclusions: Peri-implant diseases were prevalent in patients rehabilitated with dental implants and followed up for a period of 20 years. History of periodontal disease and a lack of compliance with a tailored supportive periodontal care programme were identified as risk factors for peri-implant diseases.

Objective: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing/regeneration in intrabony defects., Method and Materials: Intrabony defects were surgically created in the mandible of three minipigs. Twelve defects were randomly treated with either rAmelX and carrier (test group) or with the carrier only (control group). At 3 months following reconstructive surgery, the animals were euthanized, and the tissues histologically processed. Thereafter, descriptive histology, histometry, and statistical analyses were performed., Results: Postoperative clinical healing was uneventful. At the defect level, no adverse reactions (eg, suppuration, abscess formation, unusual inflammatory reaction) were observed with a good biocompatibility of the tested products. The test group yielded higher values for new cementum formation (4.81 ± 1.17 mm) compared to the control group (4.39 ± 1.71 mm) without reaching statistical significance (P = .937). Moreover, regrowth of new bone was greater in the test compared to the control group (3.51 mm and 2.97 mm, respectively, P = .309)., Conclusions: The present results provided for the first-time histologic evidence for periodontal regeneration following the use of rAmelX in intrabony defects, thus pointing to the potential of this novel recombinant amelogenin as a possible alternative to regenerative materials from animal origins.

Objectives: To histologically evaluate the effects of a novel human recombinant amelogenin (rAmelX) on periodontal wound healing / regeneration in recession-type defects., Materials and Methods: A total of 17 gingival recession-type defects were surgically created in the maxilla of three minipigs. The defects were randomly treated with a coronally advanced flap (CAF) and either rAmelX (test), or a CAF and placebo (control). At three months following reconstructive surgery, the animals were euthanized, and the healing outcomes histologically evaluated., Results: The test group yielded statistically significantly (p = 0.047) greater formation of cementum with inserting collagen fibers compared with the control group (i.e., 4.38 mm ± 0.36 mm vs. 3.48 mm ± 1.13 mm). Bone formation measured 2.15 mm ± 0.8 mm in the test group and 2.24 mm ± 1.23 mm in the control group, respectively, without a statistically significant difference (p = 0.94)., Conclusions: The present data have provided for the first-time evidence for the potential of rAmelX to promote regeneration of periodontal ligament and root cementum in recession-type defects, thus warranting further preclinical and clinical testing., Clinical Relevance: The present results set the basis for the potential clinical application of rAmelX in reconstructive periodontal surgery., (© 2023. The Author(s).)

Aim: To investigate the spontaneous regeneration of the implanto-mucosal and dento-gingival unit after complete removal of keratinized tissue (KT)., Materials and Methods: One hemi-mandible per dog (n = 4) was allocated to receive three dental implants (test sites, premolar region), whereas three premolars on the contralateral side were controls. After osseointegration, the entire KT (buccal + lingual) was surgically excised on all test and control sites, leaving the bone exposed. Clinical measurements were performed before excision (T 0 ) and after 12 weeks (T 1 ). Following healing, the animals were euthanized, and the specimens were histologically processed. Descriptive statistical analyses were performed., Results: Clinical measurements revealed that at T 1 , on all teeth, a band of KT was spontaneously regenerated (mean width: 2.60 ± 0.66 mm), whereas on implants, KT was detected only occasionally at mesial or distal but not at buccal sites (mean total: 0.35 ± 0.53 mm; p < .0001). Histologically, spontaneous regeneration of the dento-gingival unit was evident, displaying masticatory mucosa. At the implant sites, on the other hand, the implanto-mucosal unit was characterized by a non-keratinized epithelium and elastic fibres, indicating the characteristics encountered in alveolar mucosa., Conclusion: After excision of KT at implant sites, the spontaneous regeneration of the soft tissue is characterized by a non-keratinized epithelium typical for alveolar mucosa, while at tooth sites the spontaneous regeneration was characterized by soft tissue resembling gingiva., (© 2023 The Authors. Journal of Clinical Periodontology published by John Wiley & Sons Ltd.)

Background: Peri-implant health is characterized by the absence of clinical signs of soft tissue inflammation. Peri-implant diseases are initiated by the presence of bacterial biofilms and share a similar etiology as that involved in the onset of periodontal diseases., Purpose: To summarize available evidence on the physiopathology of peri-implant diseases with emphasis on similarities and differences with periodontal diseases., Materials and Methods: Evidence on the biologic mechanisms involved in the pathogenesis of peri-implant mucositis and peri-implantitis were explored in the recent scientific literature., Results: Findings of studies in animals and in humans indicate that experimental peri-implant mucositis leads to a larger inflammatory connective tissue infiltrate and to a higher frequency of bleeding sites around implants compared with teeth. Tissue destruction at experimental peri-implantitis sites is more pronounced compared with that at experimental periodontitis sites. Although human periodontitis and peri-implantitis lesions share similarities with respect to etiology and clinical features, they represent distinct entities from a physiopathologic point of view., Conclusions: Diagnosis of peri-implant health requires a clinical examination to confirm absence of peri-implant soft tissue inflammation. In order to make a correct diagnosis and select the appropriate therapeutic steps to manage peri-implant diseases, knowledge of their pathogenetic mechanisms is required., (© 2022 Wiley Periodicals LLC.)

Aim: To compare mean bone level (mBL) changes around dental implants with one or two adjacent teeth after a function time of ≥10 years., Materials and Methods: One hundred thirty three periodontally compromised patients (PCPs) with 551 implants enrolled in supportive periodontal care (SPC) were screened. Implants were categorized either into group TIT (tooth-implant-tooth) or into group TIG (tooth-implant-gap). MBL changes from delivery of restoration (i.e., baseline) to follow-up were calculated in millimeters and compared between implants and adjacent teeth. Survival rates and the need for surgical interventions during SPC were recorded., Results: Eighty seven patients with 142 implants were re-evaluated after a mean observation time of 14.5 ± 3.5 years. The mBL at mesial implant sites in the TIT group increased -0.07 ± 0.92 mm and decreased in the TIG group 0.52 ± 1.34 mm, respectively (95% CI: 0.04/1.14, p = .037). At distal implant sites, the mBL in the TIT group increased -0.08 ± 0.84 mm and decreased 0.03 ± 0.87 in the TIG group, respectively (95% CI: -0.20/0.42, p = .48). The overall implant loss rate was 3.5% (n = 5; 2 TIT, 3 TIG), without a statistically significant difference between the two groups (95% CI: 0.18/7.07, p = .892). Tooth loss rates (TIT: 12.3%, TIG: 12.3%) were not statistically significantly different (OR = 1.00, p = .989)., Conclusion: High tooth and implant survival rates were observed in PCPs. The presence of one or two adjacent teeth seemed to have no impact on marginal bone level changes., (© 2023 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Periodontal diseases include pathological conditions elicited by the presence of bacterial biofilms leading to a host response. In the diagnostic process, clinical signs such as bleeding on probing, development of periodontal pockets and gingival recessions, furcation involvement and presence of radiographic bone loss should be assessed prior to periodontal therapy, following active therapy, and during long-term supportive care. In addition, patient-reported outcomes such as increased tooth mobility, migration, and tilting should also be considered. More important to the patient, however, is the fact that assessment of signs of periodontal diseases must be followed by an appropriate treatment plan. Furthermore, it should be realized that clinical and radiographic periodontal diagnosis is based on signs which may not reflect the presence of active disease but rather represent the sequelae of a previous bacterial challenge. Hence, the aim of the present review is to provide a summary of clinical and radiographic diagnostic criteria required to classify patients with periodontal health or disease., (© 2023 The Authors. Periodontology 2000 published by John Wiley & Sons Ltd.)

Objectives: To evaluate the sequential osseointegration of a novel titanium implant system based on a 3D printing technology in comparison with conventional titanium implants., Material and Methods: Two novel titanium implants based on 3D printing were tested in the mandible of eight Beagle dogs. As a control, two different commercially available titanium implants were used. The implants were staged to accommodate healing periods of 2 and 6 weeks. The primary outcome variable was bone-to-implant contact (BIC) in non-decalcified tissue sections and micro-CT analysis., Results: Histomorphometrically, the proportions of tissues adjacent to the implant surfaces were similar for all implants, whereas the BIC percentage of new mineralized bone was greater for the control implants after both 2 and 6 weeks (p < .05). Micro-CT analysis revealed increasing osseous volume and BIC from 2 to 6 weeks. In contrast to the histomorphometry, the BIC evaluation with the micro-CT data revealed a significantly higher BIC for the two test implants compared with controls (p < .001). The analysis of the total implant surface area disclosed a value that was approximately double as high for the test compared to the control implants., Conclusions: The novel titanium implant system based on 3D printing yielded values for osseointegration that were adequate and satisfactory. The higher percentage of new mineralized bone in the control implants is explained by the fact of a completely different three-dimensional surface area., (© 2023 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Peri-implantitis is a plaque-associated pathologic condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant mucosa and subsequent progressive loss of supporting bone. It is a highly prevalent disease, as extensively estimated by large-population, cross-sectional studies. As peri-implant diseases represent opportunistic infections, it is reasonable to assume that nonideal conditions, local and/or general, may favor the progression of peri-implant inflammation. Some of these conditions could be a result of poor planning and/or inadequate execution of any step of the entire process treatment. This article describes the major possible factors in implant therapy that may lead to peri-implantitis. For some of these (ie, inappropriate patient selection, insufficient periodontal therapy, lack of diagnosis and management of peri-implant mucositis, erratic supportive peri-implant/periodontal therapy) there is a good level of evidence, whereas for others (ie, wrong implant placement, poor postoperative care, inadequate prosthetic reconstruction, lack of assessment and management of peri-implant soft-tissue deficiencies) there is little scientific evidence. More research is therefore needed to clearly identify the errors and/or complications possibly leading to peri-implantitis, particularly over the long term., (© 2023 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Objectives: To assess the association between the baseline radiographic defect angle and the long-term clinical outcomes following periodontal regenerative therapy with enamel matrix derivative (EMD)., Method and Materials: Baseline periapical radiographs obtained from a cohort of patients treated with periodontal regenerative therapy were digitized and the radiographic angle width between the root surface and the bony wall of the adjacent intraosseous defect was calculated and reported (in degrees). Changes in pocket probing depth (PD) and clinical attachment level (CAL) were assessed and reported (in mm). Clinical outcomes were evaluated at baseline (T0), 6 months following therapy (T1), and at the latest follow-up (T2)., Results: Thirty-eight defects in 26 patients enrolled in supportive periodontal care for a mean period of 10.4 years (range 8.0 to 15.5 years) were available for analysis. The mean PD change between T0 and T2 was 2.33 ± 1.66 mm at teeth with a defect angle width < 20 degrees and 0.86 ± 1.66 mm at teeth with a defect angle width > 30 degrees (P = .021). When the baseline radiographic angle width was < 20 degrees the probability of obtaining a CAL gain > 3 mm was 1.5-times higher (95% CI 0.19 to 13.8) at T1 and 2.5-times higher (95% CI 0.40 to 15.6) at T2 compared with defects with a radiographic angle width > 30 degrees., Conclusion: Within their limitations, these results indicate that pretherapeutic measurement of the radiographic defect angle width might provide relevant information on the short-/long-term clinical outcomes following regenerative periodontal therapy with EMD.

Partial fixed dental prostheses supported by dental implants have become a reliable long-term treatment option. Nevertheless, the replacement of two adjacent missing teeth, irrespective of location, still represents a clinical challenge. To overcome this, the use of fixed dental prostheses with cantilever extensions has gained popularity with a view to limiting morbidity, reducing costs and avoiding major surgical interventions prior to implant placement. The present review summarises the level of evidence for the use of fixed dental prostheses with cantilever extensions both in the posterior and anterior regions and indicates the advantages and disadvantages of each treatment, focusing on available medium- to long-term outcomes.

Aim: To histologically evaluate the influence of (1) loading and (2) grafting on osseointegration and peri-implant soft-tissue healing at immediately placed, self-cutting progressive tissue-level implants (TLX) in a minipig model., Materials and Methods: TLX implants (n = 56) were immediately placed following the extraction of the mandibular first and second premolars, bilaterally, in a total of n = 14 minipigs. In each animal, the implant sites were allocated to the following four groups: (1) unloaded with simultaneous grafting using a bovine bone mineral; (2) unloaded without grafting; (3) loaded with simultaneous grafting; and (4) loaded without grafting. Histomorphometric assessments at 4 and 12 weeks (n = 7 animals each) included primary (i.e., bone-to-implant contact [BIC]) and secondary outcome measures (e.g., first BIC [fBIC], junctional epithelium length [JE], connective tissue contact length [CTC], biological width [BW = JE + CTC])., Results: At 4 weeks, mean BIC values ranged from 74.5 ± 11.6% in Group 2 to 83.8 ± 13.3% in Group 1, and, at 12 weeks, from 75.5% ± 7.9% in Group 2 to 79.9 ± 8.6% in Group 1. Multivariate linear mixed regression did not reveal any associations between BIC and implant loading or grafting at 4 and 12 weeks. At 12 weeks, significantly higher fBIC values were noted in Group 2 when compared with Group 1. All groups showed comparable JE, CTC, and BW values., Conclusions: Implant loading and grafting had no major effects on osseointegration and peri-implant soft tissue healing at TLX implants., (© 2022 The Authors. Journal of Clinical Periodontology published by John Wiley & Sons Ltd.)

Objectives: To evaluate the 5-year results of single and multiple recession type (RT) 1 and 2 (Miller I to III) recessions treated with the modified coronally advanced tunnel (MCAT) and connective tissue graft (CTG) with or without an enamel matrix derivative (EMD). The main outcome variable was the stability of obtained root coverage from 6 months to 5 years., Materials and Methods: In 24 patients, both complete and mean root coverage (CRC and MRC) and gain of keratinised tissue (KT) were assessed at 6 months and 5 years after recession coverage by means of MCAT and CTG with or without EMD. Aesthetic outcomes after 5 years were evaluated using the root coverage aesthetic score (RES)., Results: At 5 years, 24 patients with a total of 43 recessions were evaluated. Eight patients (57.14%) of the test and 6 (60.0%) of the control group showed complete root coverage. MRC revealed no statistically significant differences between the two groups, with 73.87 ± 26.83% (test) and 75.04 ± 22.06% (control), respectively. KT increased from 1.14 ± 0.57 mm to 3.07 ± 2.27 mm in the test group and from 1.24 ± 0.92 mm to 3.02 ± 1.55 mm in the control group, respectively., Conclusion: Treatment of single and multiple RT 1 and 2 recessions by means of MCAT and CTG with or without EMD yielded comparable clinical improvements which could be maintained over a period of 5 years. The additional use of EMD did not influence the clinical outcomes., Clinical Relevance: The use of MCAT + CTG yielded successful coverage of single and multiple RT 1 and 2 gingival recessions, while the additional application of EMD did not seem to influence the results., (© 2022. The Author(s).)

Aim: To present the 20-year clinical outcomes of tissue-level implants in partially edentulous patients previously treated for periodontitis and in periodontally healthy patients (PHP)., Material and Methods: The original population consisted of 149 partially edentulous patients consecutively enrolled in a private specialist practice and divided into three groups: PHP, moderately periodontally compromised patients (mPCP) and severely PCP (sPCP). After successful completion of periodontal/implant therapy, patients were enrolled in an individualized supportive periodontal care (SPC) programme., Results: Eighty-four patients rehabilitated with 172 implants reached the 20-year examination. During the observation time, 12 implants were removed (i.e., 11 due to biological complications and 1 due to implant fracture), leading to an overall implant survival rate of 93% (i.e., 94.9% for PHP, 91.8% for mPCP and 93.1% for sPCP [p = .29]). At 20 years, PCP compliant with SPC did not present with significantly higher odds of implant loss compared with PHP compliant with SPC (p &gt; .05). Conversely, PCP not compliant with SPC experienced implant loss with odds ratio of 14.59 (1.30-164.29, p = .03)., Conclusions: Tissue-level implants, placed after comprehensive periodontal therapy and SPC, yield favourable long-term results. However, patients with a history of periodontitis and non-compliant with SPC are at higher risk of biological complications and implant loss., (© 2022 The Authors. Journal of Clinical Periodontology published by John Wiley & Sons Ltd.)

(1) Aim: To investigate the effect of synthetic bone substitutes, α-tricalcium phosphate (α-TCP) or bi-layered biphasic calcium-phosphate (BBCP) combined with deproteinized bovine bone mineral (DBBM), on bone formation. (2) Methods: Thirty critical size defects were randomly treated with the following five different treatment modalities: (1) negative control (NC, empty), (2) DBBM, (3) α-TCP + DBBM (1:1), (4) BBCP 3%HA/97%α-TCP + DBBM (1:1), and (5) BBCP 6%HA/94%α-TCP + DBBM (1:1). The samples, at four weeks post-surgery, were investigated by micro-CT and histological analysis. (3) Results: A similar level of new bone formation was demonstrated in the DBBM with α-TCP bone substitute groups when compared to the negative control by histomorphometry. DBBM alone showed significantly lower new bone area than the negative control ( p = 0.0252). In contrast to DBBM, the micro-CT analysis revealed resorption of the α-TCP + DBBM, BBCP 3%HA/97%α-TCP + DBBM and BBCP 6%HA/94%α-TCP + DBBM, as evidenced by a decrease of material density ( p = 0.0083, p = 0.0050 and p = 0.0191, respectively), without changing their volume. (4) Conclusions: New bone formation was evident in all defects augmented with biomaterials, proving the osteoconductive properties of the tested material combinations. There was little impact of the HA coating degree on α-TCP in bone augmentation potential and material resorption for four weeks when mixed with DBBM.

Objectives: The objective of this study is to investigate the outcomes following non-surgical therapy of peri-implantitis (PI) with or without adjunctive diode laser application., Materials and Methods: A double-blinded randomized controlled clinical trial was carried out in 25 subjects with 25 implants diagnosed with PI. Following curettage of granulation tissue, test implants (T) were treated with adjunctive application of a diode laser for 90 s (settings: 810 nm, 2.5 W, 50 Hz, 10 ms), while at control implants (C) non-activated adjunctive diode laser was applied. The entire treatment procedure was performed at days 0 (i.e., baseline), 7 and 14. The primary outcome measure was change in mean pocket probing depth (PPD). Clinical and microbiological outcomes, as well as host-derived inflammatory markers were evaluated at baseline, 3 and 6 months, while radiographic outcomes were assessed at baseline and at the 6-month follow-up., Results: No statistically significant differences with respect to baseline patient characteristic were observed. After 6 months, both test and control implants yielded statistically significant PPD changes compared with baseline (T: 1.28 and C: 1.47 mm) but without statistically significant difference between groups (p = .381). No statistically significant changes in peri-implant marginal bone levels were detected (p = .936). No statistically significant differences between test and control implants were observed with respect to microbiological and host-derived parameters (p > .05). At the 6-month follow-up, treatment success was observed in 41.7% (n = 5) of test and 46.2% (n = 6) of control patients, respectively (p = .821)., Conclusion: Repeated adjunctive application of diode laser in the non-surgical management of PI failed to provide significant benefits compared with mechanical instrumentation alone., (© 2022 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Background: Supra- and subgingival air-polishing has been used in periodontitis and gingivitis therapy for years. Low-abrasive types of powders have facilitated the application in subgingival areas. In this study, the cellular effects of a glycine powder and an erythritol/chlorhexidine (CHX) powder on human gingival fibroblasts (HGF) were investigated., Methods: HGF were obtained from sound gingiva of three healthy donors. After 12 h and 24 h of incubation time, cell viability testing and, after 24 h and 48 h, a cell proliferation assay was conducted. Additionally, the individual components erythritol and CHX were investigated for cell viability. In vitro wound healing was monitored for 48 h and scanning electron microscopy (SEM) analysis was performed after 24 h. Statistical analysis was accomplished by ANOVA and post hoc Dunnett's and Tukey's tests (p < 0.05) were performed., Results: Erythritol/CHX powder and in a lower extent, glycine powder decreased cell viability and cell proliferation. The negative effect of erythritol/CHX was mainly based on the CHX component. In vitro wound healing was negatively influenced in both types of powders compared to control. Cell size was altered in both test groups, whereas cell morphology was affected only in the erythritol/CHX group., Conclusions: The investigated powders for subgingival air-polishing can influence cell viability, morphology, and proliferation, as well as wound closure in vitro. These actions on fibroblasts are discernible, with the cytotoxic effect of erythritol/CHX powder being very clear and mainly due to the CHX component. Our results suggest that subgingivally applied powders can exert direct effects on gingival fibroblasts., Competing Interests: Declaration of Competing Interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests: Dr. Weusmann has given lectures for a powder supplier in the past but sees no competing interests., (Copyright © 2022 Elsevier GmbH. All rights reserved.)

Objectives: To report the clinical, radiographic, esthetic, and patient-reported outcomes after placement of a newly developed narrow-diameter implant (NDI) in patients with congenitally missing lateral incisors (MLIs)., Materials and Methods: Patients with MLIs with a mesio-distal distance between the canine and the central incisor of 5.9-6.3 mm received a dental implant with a diameter of 2.9 mm (Test), while a diameter of 3.3 mm (Control) was used when the distance was 6.4-7.1 mm. After healing, a cement-retained bi-layered zirconia crown was fabricated. At the 1-year follow-up (T2), implant survival rate, marginal crestal bone level (CBL) changes, biological and technical complications were registered. The esthetic outcome was assessed by using the Copenhagen index score, and the patient-reported outcomes were recorded using the OHIP-49 questionnaire., Results: One hundred patients rehabilitated with 100 dental implants Ø0.9 mm (n = 50) or Ø3.3 mm (n = 50) were included. One Ø3.3 mm implant was lost, and seven patients dropped out of the study, yielding an implant survival rate of 99% (p = 1.000). At T2 a. CBL of -0.19 ± 0.25 mm (Test) and -0.25 ± 0.31 mm (Control) was detected, with no statistically significant difference between the groups (p = .342). Good to excellent esthetic scores (i.e., 1-2) were recorded in most of cases. Technical complications (i.e., loss of retention, abutment fracture, and chipping of veneering ceramic) occurred once in three patients with no statistically significant difference between the groups (p > .05). OHIP scores did not differ significantly at follow-ups between groups (p = .110)., Conclusion: The use of Ø2.9 mm diameter implants represents as reliable a treatment option as Ø3.3 mm implants, in terms of CBL changes, biological and technical complications. Favorable esthetics and patient-reported outcomes were recorded for both groups., (© 2022 The Authors. Clinical Oral Implants Research published by John Wiley & Sons Ltd.)

Objectives: To assess the potential additional benefit of the local application of enamel matrix derivative (EMD) on the clinical outcomes following non-surgical periodontal therapy (NSPT) (steps 1 and 2 periodontal therapy)., Materials and Methods: A systematic literature search was performed in several electronic databases, including Medline/PubMed, Embase, The Cochrane Register of Central Trials (CENTRAL), LILACS, and grey literature. Only randomized controlled clinical trials (RCTs) were eligible for inclusion. Clinical attachment level (CAL) change (primary outcome), probing pocket depth (PPD), and bleeding on probing (BoP) reductions (secondary outcomes) were evaluated. The Cochrane Risk of Bias tool (RoB 2.0) was used to assess the quality of the included trials. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) between test and control sites were estimated using a random-effect model for amount of mean CAL and PPD change., Results: Six RCTs were included for the qualitative analysis, while data from 4 studies were used for meta-analysis. Overall analysis of CAL gain (3 studies) and PPD reduction (4 studies) presented WMD of 0.14 mm (p = 0.74; CI 95% - 0.66; 0.94) and 0.46 mm (p = 0.25; CI 95% - 0.33; 1.26) in favor of NSPT + EMD compared to NSPT alone respectively. Statistical heterogeneity was found to be high in both cases (I 2  = 79% and 87%, respectively)., Conclusions: Within their limitations, the present data indicate that the local application of EMD does not lead to additional clinical benefits after 3 to 12 months when used as an adjunctive to NSPT. However, due to the high heterogeneity among the studies, additional well-designed RCTs are needed to provide further evidence on this clinical indication for the use of EMD., Clinical Relevance: The adjunctive use of EMD to NSPT does not seem to additionally improve the clinical outcomes obtained with NSPT alone., (© 2022. The Author(s).)

Objective: To evaluate re-osseointegration after electrolytic cleaning and regenerative therapy of dental implants with peri-implantitis in humans., Material and Methods: Four dental implants that developed peri-implantitis underwent electrolytic cleaning followed by regenerative therapy with guided bone regeneration. All four implants developed recurrent peri-implantitis and were therefore explanted 6 to 13 months later. Radiographic bone level, probing depth, and bleeding on probing were determined at the time of surgery, 6 months later, and before implant retrieval. The peri-implant tissues were histologically and histomorphometrically analyzed., Results: All four implants demonstrated radiographic and histological bone gain, reduced probing depth, and bleeding on probing. Radiographic bone gain was 5.8 mm mesially and 4.8 mm distally for implant #1, 3.3 mm and 2.3 mm for implant #2, 3.1 mm and 0.5 mm for implant #3, and 3.5 mm and 2.8 mm for implant #4. The histometric mean and maximum vertical bone gain for implant #1 to #4 was 1.65 mm and 2.54 mm, 3.04 mm and 3.47 mm, 0.43 mm and 1.27 mm, and 4.16 mm and 5.22 mm, respectively. The percentage of re-osseointegration for implant #1 to #4 was 21.0%, 36.9%, 5.7%, and 39.0%, respectively. In one implant, the newly formed bone was deposited directly onto calculus on the implant surface., Conclusions: We found that (1) re-osseointegration is possible on a formerly contaminated implant surface and (2) the electrolytic cleaning process seems to be effective enough at sites with calculus residues., Clinical Relevance: Since re-osseointegration can be achieved by electrolytic cleaning, this decontamination technique may be considered as a future treatment concept., (© 2022. The Author(s).)

Objectives: Air-polishing has been used in the treatment of periodontitis and gingivitis for years. The introduction of low-abrasive powders has enabled the use of air-polishing devices for subgingival therapy. Within the last decade, a wide range of different low-abrasive powders for subgingival use has been established. In this study, the effects of a glycine powder and a trehalose powder on human gingival fibroblasts (HGF) were investigated., Methods: HGF were derived from three systemically and periodontally healthy donors. After 24 h and 48 h of incubation time, mRNA levels, and after 48 h, protein levels of TNFα, IL-8, CCL2, and VEGF were determined. In addition, NF-κB p65 nuclear translocation and in vitro wound healing were assessed. Statistical analysis was performed by ANOVA and post hoc Dunnett's and Tukey's tests (p < 0.05)., Results: Glycine powder significantly increased the expression of proinflammatory genes and showed exploitation of the NF-κB pathway, albeit trehalose powder hardly interfered with cell function and did not trigger the NF-κB pathway. In contrast to trehalose, glycine showed a significant inhibitory effect on the in vitro wound healing rate., Conclusion: Subgingivally applicable powders for air-polishing devices can regulate cell viability and proliferation as well as cytokine expression. Our in vitro study suggests that the above powders may influence HGF via direct cell effects. Trehalose appears to be relatively inert compared to glycine powder., Clinical Relevance: With the limitations of an in vitro design, our study suggests that in terms of cell response, trehalose-based air-polishing powders show a reduced effect on inflammation., (© 2021. The Author(s).)

(1) Aim: To immunohistochemically evaluate the effect of a volume-stable collagen scaffold (VCMX) on periodontal regeneration. (2) Methods: In eight beagle dogs, acute two-wall intrabony defects were treated with open flap debridement either with VCMX (test) or without (control). After 12 weeks, eight defects out of four animals were processed for paraffin histology and immunohistochemistry. (3) Results: All defects (four test + four control) revealed periodontal regeneration with cementum and bone formation. VCMX remnants were integrated in bone, periodontal ligament (PDL), and cementum. No differences in immunohistochemical labeling patterns were observed between test and control sites. New bone and cementum were labeled for bone sialoprotein, while the regenerated PDL was labeled for periostin and collagen type 1. Cytokeratin-positive epithelial cell rests of Malassez were detected in 50% of the defects. The regenerated PDL demonstrated a larger blood vessel area at the test (14.48% ± 3.52%) than at control sites (8.04% ± 1.85%, p = 0.0007). The number of blood vessels was higher in the regenerated PDL (test + control) compared to the pristine one ( p = 0.012). The cell proliferative index was not statistically significantly different in pristine and regenerated PDL. (4) Conclusions: The data suggest a positive effect of VCMX on angiogenesis and an equally high cell turnover in the regenerated and pristine PDL. This VCMX supported periodontal regeneration in intrabony defects.

The cross-linking of collagen matrices (Cl&#95;CM) may provide volume-stable enhanced defect regeneration when compared to non-cross-linked matrices (Ncl&#95;CM). The aim of the present study was to investigate the bone forming potential of collagen matrices (CMs) and the effects of cross-linking CMs in a rabbit calvaria defect model. (1) Empty controls ( n = 6), (2) Ncl&#95;CM ( n = 8), and (3) Cl&#95;CM ( n = 8) were selected to be observed for the healing in 10 mm critical-sized calvarial bone defects. The potential for the bone as well as the connective tissue formation were evaluated by micro-CT and histomorphometry at three months post-surgery. There were no statistically significant differences in terms of new bone volume in the defects between the groups. However, the Cl&#95;CM induced significantly greater fibrous tissue regeneration (5.29 ± 1.57 mm 2 ) when compared to the controls (3.51 ± 0.93 mm 2 ) by histomorphometry. The remnants of collagen fibers with immune cells, including macrophages and giant cells, were occasionally observed in the Cl&#95;CM group but not in the Ncl&#95;CM group. In conclusion, the cross-linking of collagen did not influence the potential for bone formation. Nevertheless, Cl&#95;CM might be advantageous for the maintenance of fibrous tissue volume without disturbing bone formation in the defects.

Bone exostosis is defined as a benign overgrowth of bone tissue of unclear origin. Rarely, bone exostosis might develop following soft tissue graft procedures like mucogingival surgical interventions (eg, FGG or subepithelial CTG). This aberration has been mainly associated with surgical trauma or fenestration of the periosteum but is still a matter of debate. The present paper (1) presents a clinical case with clinical, radiographic, and histologic findings at 30 years following application of an FGG to increase the gingival width and (2) provides a short literature review on this particular clinical condition. At the clinical examination, the FGG was firm to palpation, and the 3D images showed an area of increased radiopacity. Histologic analysis revealed localized thickening of the bone with an overlaying connective tissue covered by keratinized epithelium. The bony tissue was vital, had a convex shape, and contained many osteocytes and resting lines, demonstrating some moderate signs of bone remodeling. The connective tissue and keratinized epithelium displayed a regular thickness without any signs of inflammation. Taken together, the histologic findings failed to reveal any pathologic signs except for the presence of vital bone formed outside the bony envelope. It can be concluded that: (1) the development of a bone exostosis following a mucogingival procedure is a rare clinical sequela of uncertain etiology, and (2) surgical removal of the exostosis may be indicated accordingly with patient symptoms.

Gingival recession is a common finding in daily clinical practice. Several issues may be associated with the apical shift of the gingival margin such as dentine hypersensitivity, root caries, non-carious cervical lesions (NCCLs), and compromised aesthetics. The first step in an effective management and prevention program is to identify susceptibility factors and modifiable conditions associated with gingival recession. Non-surgical treatment options for gingival recession defects include establishment of optimal plaque control, removal of overhanging subgingival restorations, behaviour change interventions, and use of desensitising agents. In cases where a surgical approach is indicated, coronally advanced flap and tunnelling procedures combined with a connective tissue graft are considered the most predictable treatment options for single and multiple recession defects. If there is a contraindication for harvesting a connective tissue graft from the palate or the patient wants to avoid a donor site surgery, adjunctive use of acellular dermal matrices, collagen matrices, and/or enamel matrix derivatives can be a valuable treatment alternative. For gingival recession defects associated with NCCLs a combined restorative-surgical approach can provide favourable clinical outcomes. If a patient refuses a surgical intervention or there are other contraindications for an invasive approach, gingival conditions should be maintained with preventive measures. This paper gives a concise review on when and how to treat gingival recession defects., (Copyright © 2021. Published by Elsevier Inc.)

Objectives: To detect the potential influence of implant diameter and anatomic factors on the need for bone augmentation procedures (BAPs) when replacing congenitally missing lateral incisors (MLIs)., Materials and Methods: Patients with congenitally missing MLIs with a mesio-distal distance between the canine and the central incisor of 5.9-6.3 mm received a Ø2.9 mm implant while Ø3.3 mm implants were placed when the distance was 6.4-7.1 mm. The following linear measurements were recorded using a calliper: width of the alveolar process (WAP), width of the bony alveolar ridge (WAR) and thickness of the facial bone after implant osteotomy (TFB). Guided bone regeneration was performed in case of fenestration- or dehiscence-type defects or a thin TFB (<1.7 mm)., Results: Fifty Ø2.9 mm and 50 Ø3.3 mm were included in 100 patients. WAP and WAR did not differ between the groups (p > .05). TFB was statistically significant larger in the Ø2.9 group (1.75 ± 0.59 mm) compared to the Ø3.3 group (1.5 ± 0.63 mm) (p = .041). Fenestration-type defects (p = .005) and a thin facial bone wall (p = .045) was observed more frequently in the Ø3.3 compared to the Ø2.9 group. Correspondingly, BAP was indicated more frequently in the Ø3.3 compared to the Ø2.9 group (p = .017). WAP, MD and WAR were statistically significant correlated to the need for BAP (p < .001). As independent variable, only WAR influenced the probability of BAP (p < .001)., Conclusion: The use of 2.9 diameter implants was correlated to a reduced frequency of BAP compared to 3.3 mm implants, without reaching a statistically significant difference. Measurement of the WAP provides the clinician useful information to predict BAP., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Aim: To histologically evaluate the effect of a new collagen matrix on periodontal regeneration., Materials and Methods: Two-wall intrabony defects were surgically created bilaterally distally to the maxillary first and third pre-molars in beagle dogs. The defects were randomly allocated to open flap debridement either with (test) or without (control) a volume-stable collagen matrix (VCMX). After 12 weeks, the dogs were euthanized, and the specimens histologically processed. Descriptive, histomorphometrical (vertical gain of periodontal tissues) and statistical analyses were then performed., Results: Healing was uneventful in most cases. Residual VCMX was still present and showed integration into new bone, new periodontal ligament, connective tissue and, in some specimens, into new cementum. Periodontal regeneration occurred to a varying extent in both groups. New continuous cementum and new bone formation were statistically significantly greater in the test group (4.12 mm and 3.28 mm, respectively) than in the control group (1.54 mm and 2.47 mm, respectively) (p = .009 and p = .037, respectively). The junctional epithelium was longer in the control group (2.21 mm) than in the test group (1.49 mm, p = .16)., Conclusion: The present results have for the first time provided histologic evidence for the potential of this novel VCMX to facilitate periodontal regeneration thus warranting further pre-clinical and clinical testing., (© 2021 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

The aim of this study was to evaluate the influence of additional hydroxyapatite (HA) in collagen-based matrices (CM) and membrane placement on bone formation in calvarial defects. Critical size defects in the calvaria of 16 New Zealand White Rabbits were randomly treated with CM or mineralized collagen-based matrices (mCM). Half of the sites were covered with a collagen membrane. Animals were euthanized after 12 weeks of healing. The samples were studied by micro-CT and histology. Newly formed lamellar bone was observed in all samples at the periphery of the defect. In the central areas, however, new bone composed of both woven and lamellar bone was embedded in the soft tissue. Samples treated with mCM showed more residual biomaterial and induced more small bony islands in the central areas of the defects than samples with CM. Nevertheless, a complete defect closure was not observed in any of the samples at 12 weeks. Membrane placement resulted in a decrease in bone density and height. Significant differences between the groups were revealed only between CM groups with and without membrane coverage for bone height in the central area of the defect. Neither mineralization of CM nor membrane placement improved the osteogenic capacity in this particular defect. Nevertheless, mineralisation influenced bone density without a membrane placement and bone volume underneath a membrane. CM may be used as a scaffold in bone regeneration procedures, without the need of a membrane coverage. Further preclinical studies are warrant to optimise the potential of mCM.

Objective: To analyse the citrulline level in the periodontium in association with the presence of or antibody levels against Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis., Design: Gingival crevicular fluid (GCF), subgingival biofilm and blood serum were sampled from 98 subjects (26 with RA, 72 without RA (NoRA)). GCF was analyzed for the level of citrulline, for interleukin (IL)-1β, IL-17, IL-10 and monocyte-chemoattractant protein (MCP)-1. Microorganisms were identified in subgingival biofilms. Antibodies againstP. gingivalis, and Aggregatibacter actinomycetemcomitans were quantified in serum., Results: GCF citrulline level was the lowest (by trend) in NoRA group without periodontitis. In NoRA, but not in RA an association between GCF citrulline level and P. gingivalis antibody levels was found and the GCF citrulline levels were higher in P. gingivalis positive samples. Any association of A. actinomycetemcomitans with GCF citrulline level did not exist. A model of univariate variance analysis (p = 0.001) showed a dependence of GCF citrulline level from the number of sites with PD (probing depth) ≥5 mm (p = 0.003) and the GCF MCP-1/CCL2 level (p = 0.019). Compared with NoRA in RA the number of teeth was lower, the number of sites with PD ≥ 5 mm was less, GCF levels of interleukin-17 and MCP-1/CCL2 were higher and those of IL-10 lower. Yeasts were only cultured in 15 RA patients (p < 0.001)., Conclusion: Citrullination in periodontium might be associated with P. gingivalis supporting the potential role as a trigger in the development of RA. Pathogenesis of periodontal disease in RA patients seems to differ from that in NoRA and should be investigated further., Competing Interests: Declaration of Competing Interest Authors declare no conflict of interest., (Copyright © 2020. Published by Elsevier Ltd.)

Objectives: The potential effect of enamel matrix derivative (EMD) on wound healing following recession coverage surgery is still controversially discussed in the literature. The aim of this randomised, controlled, single blinded clinical study was, therefore, to investigate clinically and immunologically the potential effects of EMD on early wound healing and clinical results following treatment of single and multiple gingival recessions by the modified coronally advanced tunnel technique (MCAT) and subepithelial connective tissue graft (sCTG)., Materials and Methods: A total of 40 systemically healthy patients with Miller class I, II or III single or multiple gingival recessions were treated with MCAT + sCTG with or without EMD. Patients were consecutively enrolled and randomly assigned to test or control treatment. Inflammatory markers (interleukin (IL)-1β, IL-8, IL-10 and matrix metalloprotease (MMP)-8) were measured at baseline, 2 days and 1 week postoperatively. The following clinical parameters were assessed at baseline and at 6 months postoperatively: Recession Depth (RD), Recession Width (RW), Width of Keratinized Tissue (KT) and Probing Depth (PD). Patient-reported outcomes were analysed by means of a visual analogue scale., Results: No statistically significant differences were detected between the 2 groups in terms of inflammatory markers and patient-reported outcomes during early wound healing. In the test group, RD was reduced from 4.0 ± 1.2 mm at baseline to 0.9 ± 1.3 mm at 6 months (p < 0.001), while the corresponding values in the control group were 4.5 ± 2.0 mm at baseline and 1.0 ± 1.0 mm at 6 months, respectively. At 6 months, mean root coverage measured 78 ± 26% in the test group and 77 ± 18% in the control group, respectively., Conclusion: Within their limits, the present data have failed to show an influence of EMD on the clinical and immunological parameters related to wound healing following recession coverage surgery using MCAT and sCTG., Clinical Relevance: Early wound healing following recession coverage by means of MCAT and sCTG does not seem to be influenced by the additional application of EMD.

Objectives: To evaluate the healing of multiple adjacent type 1 and 2 gingival recessions (RT1 and RT2) treated with the modified coronally advanced tunnel (MCAT) or the laterally closed tunnel (LCT) in conjunction with a cross-linked hyaluronic acid and subepithelial palatal connective tissue grafts., Method and Materials: Fifteen healthy patients exhibiting multiple adjacent mandibular or maxillary RT1 and RT2 of a depth of ≥ 2 mm, were treated with the MCAT or LCT in conjunction with cross-linked hyaluronic acid and subepithelial palatal connective tissue grafts. Results were assessed at baseline and after a minimum of 6 months. The primary outcome variable was root coverage. Esthetic outcomes were evaluated on photographs using the root coverage esthetic score., Results: Postoperative pain and discomfort were low and no complications occurred. Data analyses were performed at patient level. After a mean follow-up of 17 ± 5.4 months, statistically significant root coverage was obtained in all 15 cases (P < .0001). Complete root coverage was obtained in 3 out of 15 cases (20%). Root coverage amounted to > 95% in three patients, was between 90% and 95% in four patients, and reached 87.5% in another patient. In three further patients root coverage measured 75%, 77%, and 64.6%, respectively. Mean root coverage measured 85.1 ± 23.2%. Mean keratinized tissue width increased from 2.5 ± 1.0 mm to 3.7 ± 0.7 mm (P < .0001) from baseline to follow-up, while mean probing depth showed no statistically significant changes (1.3 ± 0.5 mm vs 1.5 ± 0.5 mm). The mean root coverage esthetic score was 7.9 ± 1.9, while in the three cases exhibiting complete root coverage, a maximum root coverage esthetic score (10) was given for all treated teeth., Conclusion: Within their limits, the present results indicate that the described treatment approach may lead to predictable root coverage of multiple mandibular and maxillary RT1 and RT2.

Objectives: To evaluate the potential added benefit of the topical application of hyaluronic acid (HA) on the clinical outcomes following non-surgical or surgical periodontal therapy., Materials and Methods: A systematic search was performed in Medline, Embase, Cochrane, Web of Science, Scopus and Grey literature databases. The literature search was preformed according to PRISMA guidelines. The Cochrane risk of bias tool was used in order to assess the methodology of the included trials. Weighted mean differences (WMDs) and 95% confidence intervals (CIs) between the treatment and controls were estimated using the random-effect model for amount of bleeding on probing (BOP), probing depth (PD) reduction and clinical attachment level (CAL) gain. In order to minimize the bias and to perform meta-analysis, only randomized clinical studies (RCTs) were selected., Results: Thirteen RCTs were included: 11 on non-surgical periodontal treatment and two on surgical periodontal treatment. Overall analysis of PD reduction, CAL gain and BOP reduction in non-surgical therapy with adjunctive HA presented WMD of - 0.36 mm (95% CI - 0.54 to - 0.19 mm; p < 0.0001), 0.73 mm (95% CI 0.28 to 1.17 mm; p < 0.0001) and - 15% (95% CI - 22 to - 8%; p < 0.001) respectively, favouring the application of HA. The overall analysis on PD and CAL gain in surgical therapy with adjunctive HA presented WMD of - 0.89 mm (95% CI - 1.42 to - 0.36 mm; p < 0.0001) for PD reduction and 0.85 mm (95% CI 0.08 to 1.62 mm; p < 0.0001) for CAL gain after 6-24 months favouring the treatment with HA. However, comparison presented considerable heterogeneity between the non-surgical studies and a high risk of bias in general., Conclusions: Within their limits, the present data indicate that the topical application of HA may lead to additional clinical benefits when used as an adjunctive to non-surgical and surgical periodontal therapy. However, due to the high risk of bias and heterogeneity, there is a need for further well-designed RCTs to evaluate this material in various clinical scenarios., Clinical Relevance: The adjunctive use of HA may improve the clinical outcomes when used in conjunction with non-surgical and surgical periodontal therapy.