Factors influencing outcomes of surgical therapy of peri-implantitis: A secondary analysis of 1-year results from a randomized clinical study.

AIM: To identify predictors of treatment outcomes following surgical therapy of peri-implantitis. MATERIALS AND METHODS: We performed a secondary analysis of data from a randomized controlled trial (RCT) comparing access flap with or without bone replacement graft. Outcomes at 12 months were probing pocket depth (PPD), bleeding on probing (BOP), soft-tissue recession (REC) and marginal bone level (MBL) change. Multilevel regression analyses were used to identify predictors. We also built an explanatory model for residual signs of inflammation. RESULTS: Baseline PPD was the most relevant predictor, showing positive associations with final PPD, REC and MBL gain, and negative association with probability of pocket closure. Smokers presented higher residual PPD. Absence of keratinized mucosa at baseline increased the probability of BOP but was otherwise not indicative of outcomes. Plaque at 6 weeks was detrimental in terms of residual PPD and BOP. Treatment allocation had an effect on REC. Final BOP was explained by residual PPD ≥6 mm and plaque at more than two sites. CONCLUSIONS: Baseline PPD was the most relevant predictor of the outcomes of surgical therapy of peri-implantitis. Pocket closure should be a primary goal of treatment. Bone replacement grafts may be indicated in aesthetically demanding cases to reduce soft-tissue recession. The importance of smoking cessation and patient-performed plaque control is also underlined.

Onset of periodontitis - a registry-based cohort study.

OBJECTIVES: The present retrospective registry-based cohort study aimed to identify parameters associated with the onset of periodontitis in young adults. MATERIAL AND METHODS: A total of 345 Swedish subjects were clinically examined at age 19 years (as part of an epidemiological survey) and then followed up to 31 years through the Swedish Quality Registry for Caries and Periodontal diseases (SKaPa). The registry data including periodontal parameters were obtained for the period 2010-2018 (23-31 years). Logistic regression and survival models were used to identify risk factors for periodontitis (PPD ≥6 mm at ≥2 teeth). RESULTS: The incidence of periodontitis during the 12-year observation period was 9.8%. Cigarette smoking (modified pack-years; HR 2.35, 95%CI 1.34-4.13) and increased probing pocket depth (number of sites with PPD 4-5 mm; HR 1.04, 95%CI 1.01-1.07) at 19 years were risk factors for periodontitis in subsequent young adulthood. No statistically significant association was identified for gender, snuff use, plaque and marginal bleeding scores. CONCLUSION: Cigarette smoking and increased probing pocket depth (≥4 mm) in late adolescence (19 years) were relevant risk factors for periodontitis in young adulthood. CLINICAL RELEVANCE: Our study identified cigarette smoking and increased probing depth in late adolescence as relevant risk factors of periodontitis in young adulthood. Preventive programs should therefore consider both cigarette smoking and probing pocket depths in their risk assessment.

Modified free gingival graft technique for treatment of gingival recession defects at mandibular incisors: A randomized clinical trial.

BACKGROUND: The aim of this study was to evaluate clinical and patient-reported outcomes following surgical root coverage at RT1 gingival recession defects at mandibular incisors, using either a conventional free gingival graft (FGG) or a modified FGG (ModFGG). METHODS: Total of 30 patients with RT1 gingival recessions at mandibular incisors were enrolled and randomly allocated to either a control (FGG) or test group (ModFGG). Evaluations of clinical changes (recession depth, height of keratinized tissue) and patient satisfaction were performed over a follow-up period of 12 months. Post-surgical changes of keratinized tissue height (shrinkage) were assessed from 1 month and onward. RESULTS: ModFGG resulted in more pronounced root coverage at 1 year compared to FGG (91.8% vs. 60.7%, p < 0.001). Height of keratinized tissue was improved by 4.2 and 2.2 mm (p < 0.001), respectively, with significantly less shrinkage in ModFGG. Post-surgical morbidity was significantly lower for ModFGG at 2 weeks and patient satisfaction was significantly higher 12 months after treatment (9.1 vs. 5.4; p < 0.001). CONCLUSIONS: ModFGG represents a valid approach for the management of RT1 recession defects at mandibular incisors. The technique is superior to traditional FGG in terms of root coverage, the gain of keratinized tissue height, and patient satisfaction.

Furcation involvement and tooth loss: A registry-based retrospective cohort study.

AIM: This registry-based retrospective cohort study aimed to evaluate the impact of furcation status on the risk for molar loss. MATERIALS AND METHODS: Subjects with and without furcation involvement (FI) in 2010/2011 were identified in a nationwide registry in Sweden (age- and gender-matched sample: 381,450 subjects; 2,374,883 molars). Data on dental and periodontal status were extracted for the subsequent 10-year period. Impact of FI (at baseline or detected during follow-up) on molar loss (i.e., tooth extraction) was evaluated through multilevel logistic regression and survival analyses. RESULTS: FI had a significant impact on molar loss. FI degrees 2 and 3 resulted in adjusted risk ratios of 1.67 (95% confidence interval [CI] 1.63-1.71) and 3.30 (95% CI 3.18-3.43), respectively. Following the first detection of deep FI (degrees 2-3), estimated survival decreased by 4% at 5 years and 8% at 10 years. In addition to FI, endodontic status and probing depth were relevant risk factors for molar loss. CONCLUSIONS: Furcation status had a clinically relevant impact on the risk for molar loss. Following first detection of deep FI, however, the decline in molar survival was minor.

Efficacy of access flap and pocket elimination procedures in the management of peri-implantitis: A systematic review and meta-analysis.

AIM: To evaluate the efficacy of access flap and pocket elimination procedures in the surgical treatment of peri-implantitis. MATERIALS AND METHODS: Systematic electronic searches (Central/MEDLINE/EMBASE) up to March 2022 were conducted to identify prospective clinical studies evaluating surgical therapy (access flap or pocket elimination procedures) of peri-implantitis. Primary outcome measures were reduction of probing depth (PD) and bleeding on probing (BOP). Risk of bias was evaluated according to study design. Meta-analysis and meta-regression were performed. Results were expressed as standardized mean effect with 95% confidence interval (CI). RESULTS: Evidence from studies directly comparing surgical with non-surgical therapy is lacking. Based on pre-post data originating from 13 prospective patient cohorts, pronounced reductions of PD (standardized mean effect: 2.2 mm; 95% CI 1.8-2.7) and BOP% (27.0; 95% CI 19.8-34.2) as well as marginal bone level gain (0.2 mm; 95% CI -0.0 to 0.5) were observed at evaluation time points ranging from 1 to 5 years. Wide prediction intervals suggested a high degree of heterogeneity. Reduction of mean PD increased by 0.7 mm (95% CI 0.5-0.9) for every millimetre in increase of mean PD at baseline. During the follow-up period ranging from 1 to 5 years, disease recurrence occurred frequently and implant loss was not uncommon. CONCLUSIONS: Access flap and pocket elimination surgery are effective procedures in the management of peri-implantitis, although rates of disease recurrence during 5 years were high. Treatment outcomes were affected by baseline conditions.

Prevention and management of peri-implant mucositis and peri-implantitis: A systematic review of outcome measures used in clinical studies in the last 10 years.

OBJECTIVES: To evaluate outcome measures, methods of assessment, and analysis in clinical studies on the prevention and management of peri-implant mucositis and peri-implantitis. METHODS: Systematic electronic searches (CENTRAL/MEDLINE/SCOPUS) up to April 2021 were conducted to identify longitudinal clinical studies with ≥10 patients on either the prevention or management of peri-implant diseases. Outcome measures of this analysis were the choice of outcome measures, methods of assessment, and analytical methods. Risk of bias was evaluated according to study design. Data were extracted into evidence tables and outcomes were analysed in a descriptive manner. RESULTS: The analysis of the 159 selected studies revealed that probing pocket depth (PPD) and bleeding/suppuration on probing (BOP) were reported in 89% and 87% of all studies, respectively. Additional outcome measures included plaque scores (reported in 64% of studies), radiographic outcomes (49%), soft tissue dimensions (34%), and composite outcomes (26%). Adverse events (8%) and patient-reported outcomes (6%) were only rarely mentioned. A primary outcome measure was clearly defined only in 36% of studies. Data on PPD, radiographic outcomes, and soft tissue dimensions were primarily reported as mean values and rarely as frequency distributions. For radiographic outcomes and soft tissue dimensions, it was frequently unclear how clustered data were handled. CONCLUSIONS: PPD and BOP were routinely reported in studies on the prevention and management of peri-implant mucositis and peri-implantitis, while composite outcomes, adverse events, and patient-reported outcomes were only infrequently described.

Prevention and management of peri-implant mucositis and peri-implantitis: A systematic review of outcome measures used in clinical studies in the last 10 years.

OBJECTIVES: To evaluate outcome measures, methods of assessment, and analysis in clinical studies on the prevention and management of peri-implant mucositis and peri-implantitis. METHODS: Systematic electronic searches (CENTRAL/MEDLINE/SCOPUS) up to April 2021 were conducted to identify longitudinal clinical studies with ≥10 patients on either the prevention or management of peri-implant diseases. Outcome measures of this analysis were the choice of outcome measures, methods of assessment, and analytical methods. Risk of bias was evaluated according to study design. Data were extracted into evidence tables and outcomes were analysed in a descriptive manner. RESULTS: The analysis of the 159 selected studies revealed that probing pocket depth (PPD) and bleeding/suppuration on probing (BOP) were reported in 89% and 87% of all studies, respectively. Additional outcome measures included plaque scores (reported in 64% of studies), radiographic outcomes (49%), soft tissue dimensions (34%), and composite outcomes (26%). Adverse events (8%) and patient-reported outcomes (6%) were only rarely mentioned. A primary outcome measure was clearly defined only in 36% of studies. Data on PPD, radiographic outcomes, and soft tissue dimensions were primarily reported as mean values and rarely as frequency distributions. For radiographic outcomes and soft tissue dimensions, it was frequently unclear how clustered data were handled. CONCLUSIONS: PPD and BOP were routinely reported in studies on the prevention and management of peri-implant mucositis and peri-implantitis, while composite outcomes, adverse events, and patient-reported outcomes were only infrequently described.

Scientific rationale for study: In 2012, recommendations on study design, key outcome measures, and reporting in clinical studies on the prevention and management of peri-implant diseases were presented. We aimed to evaluate how these recommendations were adapted and utilized in relevant studies published during the last decade. Principal findings: Recommendations on outcome measures and reporting in clinical studies on the prevention and management of peri-implant mucositis and peri-implantitis were only partially followed. Practical implications: When evaluating the evidence on the prevention and management of peri-implant diseases, the clinician should be aware of the limitations in terms of choice of outcome measures and data reporting.

Systematic review on the association between genetic polymorphisms and dental implant-related biological complications.

OBJECTIVES: The aim of this systematic review was to evaluate the association between specific genetic polymorphisms and dental implant-related biological complications in patients having a follow-up period of at least 12-months post-loading. MATERIAL AND METHODS: A sensitive search strategy was developed to identify implant-related genetic-association studies. This was performed by searching five databases. A three-stage screening (titles, abstract, full text) was carried out in duplicate and independently by two reviewers. Assessment was carried out according to the suggested scale for quality assessment of periodontal genetic-association studies and adapted to genetic analyses of implant-related studies leading to an overall final score 0-20 based on the summation of positive answers. RESULTS: The initial search resulted in 1838 articles. Sixty-seven full-text articles were assessed for eligibility and four studies met the defined inclusion criteria. IL-6 G174C, TNF-α -308, IL-1A-889 and IL-1B+3954 and CD14-159 C/T polymorphisms were evaluated. The quality assessment scores ranged from 6 to 11 positive answers from out of a maximum score of 20. The great heterogeneity among the studies did not allow a meta-analysis. CONCLUSIONS: The published evidence on genetic predisposition and implant biologic complications is limited. The small number of identified studies evaluating the association between genetic polymorphisms and peri-implant disease presented methodological and reporting inadequacies. Thus, the potential link between genetic polymorphisms and biological complications should be further investigated and clarified through well-designed clinical studies on adequately powered and appropriately included study populations.

A comparative study on periodontitis and periodontitis-associated bacteria in Somali and non-Somali children and adolescents living in Trollhättan, Sweden.

The reported prevalence of periodontitis in children and adolescents varies considerably between populations globally. This cross-sectional study compares clinical and microbiological findings on 83 Somali immigrants and 96 non-Somali children aged 10-17 years old living in Trollhättan, Sweden. The clinical examination included registration of bleeding on probing, plaque, and calculus on incisors and first molars. The distance between cemento-enamel junction and bone level was measured on bitewing radiographs. Pooled microbiological samples (1 µL) were taken from the mesial surface of 16, 11, 31, 36, and analyzed by culture and real-time polymerase chain reaction for seven periodontal associated bacterial species. The Somali participants had poorer oral hygiene and more bleeding, plaque, and calculus. Ten of the Somali but none of the non-Somali participants showed periodontal breakdown (radiographical bone loss > 3 mm), corresponding to a prevalence of 12% (95% CI: 5.9, 21.0%). The presence of A. actinomycetemcomitans was almost exclusively associated with Somali participants. Further, the JP2 clone was found in five Somalis (including two periodontitis cases) confirming the association of this clone with African populations. The Somali group showed significantly higher frequencies and numbers of Porphyromonas gingivalis and Treponema denticola, implying a mature and adult type of subgingival microbiota.

Endodontic retreatment versus dental implants of teeth with an uncertain endodontic prognosis: 3-year results from a randomised controlled trial.

PURPOSE: To ascertain whether in the presence of a previously endodontically treated tooth with periapical pathology and/or symptoms and an uncertain prognosis, it is better to endodontically retreat it or to replace the tooth with a single-implant-supported crown. MATERIALS AND METHODS: Twenty patients requiring the treatment of a previously endodontically treated tooth, with periapical pathology and/or symptoms of endodontic origin and an uncertain prognosis, as judged by the recruiting investigator, were randomly allocated to endodontic retreatment (Endo group, 10 patients) or tooth extraction and replacement with an implant-supported crown (Implant group, 10 patients) according to a parallel-group design at a single centre. Patients were followed to 3 years after completion of the treatment. Outcome measures were: failure of the procedure, complications, marginal bone level changes at both teeth and implants, endodontic radiographic success (teeth only), number of patients' visits and days to complete the treatment, patients' chair time, costs, aesthetics assessed using the pink aesthetic score (PES) for the soft tissues and the white aesthetic score (WES) for the tooth/crown recorded by independent assessors. RESULTS: No patient dropped out. One endodontically retreated tooth fractured and another had a crown loosening. There were no statistically significant differences for treatment failure or complications (difference in proportions = 0.10; 95% CI: -0.09 to 0.29; P (Fisher exact test) = 1.000). The mean marginal bone levels at endodontic retreatment/implant insertion were 2.10 ± 0.66 mm for the Endo group and 0.05 ± 0.15 mm for the Implant group. Three years after completion of the treatment, teeth lost on average 0.23 ± 0.82 mm and implants 0.62 ± 0.68 mm, the difference not being statistically significant (mean difference = -0.39 mm; 95% confidence interval [CI]: -1.12 to 0.33; P (t test) = 0.267). Three years after completion of the endodontic retreatment, of the four teeth that originally had a periapical radiolucency, one was lost, two showed complete healing, and one showed radiographic improvement. There were no statistically significant differences for the number of patients' visits (Endo = 6.67 ± 0.71; Implant = 6.10 ± 0.74; mean difference = 0.57; 95% CI: -0.14 to 1.27; P (t test) = 0.106). It took significantly more days to complete the implant rehabilitation (Endo = 61 ± 12.97; Implant = 191.40 ± 75.04; mean difference = -130.40; 95% CI: -184.45 to -76.35; P (t test) < 0.001) but less patients' chair time (Endo = 629.44 ± 43.62 min; Implant = 326 ± 196.99 min; mean difference = 303.44; 95% CI: 160.87 to 446.02; P (t test) = 0.001). Implant treatment was significantly more expensive (Endo = €1,588.89 ± 300.81; Implant = €2,095 ± 158.90; mean difference = €-506.11; 95% CI: -735.41 to -276.82; P (t test) < 0.001). Three years after treatment completion, mean PES were 11.11 ± 1.97 and 6.50 ± 2.46 and mean WES were 7.78 ± 1.30 and 6.80 ± 2.39 in the Endo group and Implant group, respectively. Soft tissues aesthetics (PES) were significantly better at endodontically retreated teeth (mean difference 4.61; 95% CI: 2.44 to 6.78; P (t test) < 0.001) whereas no significant differences were observed for tooth aesthetics (WES) (mean difference 0.98; 95% CI: -0.89 to 2.85; P (t test) = 0.281) between treatments. CONCLUSIONS: The present preliminary results suggest that both endodontic retreatment and replacement of previously endodontically treated teeth with persisting pathology and a dubious endodontic prognosis provided similar short-term success rates. Aesthetics of the soft tissues and time needed to complete treatment were in favour of endodontic retreatment whereas implant rehabilitation required half of the chair time than endodontic retreatment, but was significantly more expensive. Much larger patient populations and longer follow-ups are needed to fully answer this question; however, in this scenario the less invasive endodontic retreatment could be the first therapeutic option to be considered.

Immediate loading of occluding definitive partial fixed prostheses vs non-occluding provisional restorations - 3-year post-loading results from a pragmatic multicentre randomised controlled trial.

PURPOSE: To compare the clinical outcome of dental implants restored with definitive occluding partial fixed prostheses within 1 week after implant placement with immediate non-occluding provisional restorations to be replaced by definitive prostheses after 4 months. MATERIALS AND METHODS: Forty partially edentulous patients treated with one to three dental implants, at least 8.5 mm long and 4.0 mm wide, inserted with a torque of at least 35 Ncm, were randomised in two groups of 20 patients each, to be immediately loaded with partial fixed prostheses. Patients in one group received one definitive screw-retained, metal-ceramic prosthesis in occlusion within 1 week after placement. Patients in the other group received one non-occluding provisional acrylic reinforced prosthesis within 24 h of implant placement. Provisional prostheses were replaced by definitive ones after 4 months. The follow-up for all patients was 3 years post-loading. Outcome measures were prosthesis and implant failures, any complications, peri-implant marginal bone level changes, aesthetic evaluation by a dental practitioner, patient satisfaction, chair time and number of visits at the dental office from implant placement to delivery of definitive restorations. RESULTS: Three patients dropped out, one from the non-occlusal group and two from the occlusal group. Two immediately occlusally loaded implants with their related definitive prostheses failed early (difference in proportions = 0.10; 95% CI = -0.03 to 0.23; P = 0.488). Five patients from the occlusally loaded group were affected by six complications vs three patients (three complications) in the non-occlusally loaded group. The difference in proportions was not statistically significant (difference in proportions = 0.08; 95% CI = -0.17 to 0.34; P = 0.697). Three years after loading, patients subjected to occlusal loading lost an average of 1.13 mm of peri-implant bone vs 1.03 mm of patients restored with non-occluding definitive partial fixed prostheses. There were no statistically significant differences for marginal bone level changes between the two groups (mean difference = 0.10 mm; 95% CI -0.62 to 0.82; P = 0.779). No significant were the differences for pink aesthetic scores (7.09 vs 6.90; P = 0.873); for aesthetics evaluated by patients (Mann-Whitney U test P = 0.799) and function satisfaction (Mann-Whitney U test P = 0.578). Significantly less chair time (mean difference -38.00; 95% CI -58.96 to -17.04; P = 0.001) and number of visits (mean difference -2.15; 95% CI -2.77 to -1.53; P < 0.001) were required for the immediate definitive prosthesis group. CONCLUSIONS: This study did not provide a conclusive answer, but suggests that immediate occlusal loading by manufacturing immediate definitive partial fixed prostheses decreases chair time and number of visits.

Natural or palatal positioning of immediate post-extractive implants in the aesthetic zone? 1-year results of a multicentre randomised controlled trial.

PURPOSE: To evaluate whether there is a difference in aesthetic outcomes positioning immediate post-extractive implants in the natural position (where the tooth should have been in relation to adjacent teeth/implants) or about 3 mm more palatally. MATERIALS AND METHODS: Just after tooth extraction, 30 patients requiring one single immediate maxillary post-extractive implant, from second to second premolar, were randomly allocated to receive either an implant positioned in the natural "central" position where the tooth should have been (central group; 15 patients) or about 3 mm more palatally (palatal group; 15 patients) according to a parallel group design at three different centres. When needed, sites were reconstructed and bone-to-implant gaps were filled with granules of anorganic bovine bone, covered by resorbable collagen barriers. Implants were left submerged for 4 months and rehabilitated with provisional crowns, replaced after 4 months by metal-ceramic definitive crowns. Patients were followed to 1 year after loading. Outcome measures were: crown and implant failures, complications, aesthetics assessed using the pink esthetic score (PES), peri-implant marginal bone level changes and patient satisfaction, recorded by blinded assessors. RESULTS: Two patients from the palatal group dropped-out up to 1 year after loading. One implant failed in each group (6.7%), the difference being not statistically significant (difference in proportion = -0.01; 95% CI -0.20 to 0.18; P (Fisher's exact test) = 1.000). One patient from the central group was affected by one complication, vs two palatal group patients (two complications); the difference being not statistically significant (difference in proportion = -0.09; 95% CI -0.32 to 0.15; P (Fisher's exact test) = 0.583). One year after loading, the mean PES was 9.93 ± 2.67 for the central and 8.75 ± 4.37 for the palatal group; the difference being not statistically significant (mean difference = 1.18; 95% CI: -1.87 to 4.23; P (t test) = 0.427). One year after loading, patients in the central group lost on average 0.23 ± 0.17 mm of peri-implant marginal bone and those of the palatal group 0.24 ± 0.25 mm, the difference being not statistically significant (mean difference = -0.01; 95% CI: -0.23 to 0.21; P (t test) = 0.926). Patients in both groups were equally satisfied at 1 year after loading for both function and aesthetics (P (Mann-Whitney U test) = 0.494 and P (Mann-Whitney U test) = 0.076, respectively). CONCLUSIONS: These preliminary results suggest that positioning of immediate post-extractive implants 3 mm more palatally is not improving aesthetics, however, the sample size of the present study was limited, thus larger trials are needed to confirm of reject the present findings.

Immediate vs early loading of 6.6 mm flapless-placed single implants: 9 years after-loading report of a split-mouth randomised controlled trial.

PURPOSE: To evaluate the long-term effectiveness of 6.6 mm long flapless-placed single implants loaded immediately or early loaded at 6 weeks. MATERIALS AND METHODS: Thirty patients each received two single Nanotite External Hex Biomet 3i implants, which were then randomly allocated to be either immediately or early loaded, according to a split-mouth design. Implants had to be inserted with a torque superior to 40 Ncm. Provisional crowns were put in slight occlusal contact and replaced by definitive crowns 3 months after loading. Patients were followed for 9 years after loading. Outcome measures were implant failures, biological and biomechanical complications, peri-implant marginal bone level changes and patient preference. RESULTS: A total of 29 implants were immediately loaded, while 31 were early loaded. Nine years after loading, three patients dropped out. One implant failed in each group within 2 months after loading. One patient asked for the immediately loaded crown to be remade for aesthetic reasons and then again to have both metal-ceramic crowns replaced by full ceramic crowns. Another patient had his immediately loaded crown remade after repeated debonding. Six patients from each group experienced complications, the difference being not statistically significant (difference of proportions = 0.00; 95% CI -0.20 to 0.20, P = 1.000). Peri-implant bone loss was 0.60 mm for patients with immediately loaded implants and 0.46 mm for early loaded ones, which was not significantly different (mean difference = 0.14 mm, 95% CI -0.13 to 0.41, P = 0.283). All but one patient had no preference for either procedure after 9 years. CONCLUSIONS: Flapless-placed 6.6 mm long single implants can be immediately loaded and remain successful up to 9 years after loading. Conflict-of-interest statement:

4 mm long vs longer implants in augmented bone in posterior atrophic jaws: 1-year post-loading results from a multicentre randomised controlled trial.

PURPOSE: To evaluate whether 4.0 mm short dental implants could be an alternative to augmentation with xenographs in the maxilla and placement of at least 10.0 mm long implants in posterior atrophic jaws. MATERIALS AND METHODS: A group of 40 patients with atrophic posterior (premolar and molar areas) mandibles with 5.0 mm to 6.0 mm bone height above the mandibular canal and 40 patients with atrophic maxillas having 4.0 mm to 5.0 mm below the maxillary sinus, were randomised according to a parallel group design to receive between one and three 4.0 mm long implants or one to three implants of at least 10.0 mm long in augmented bone, at two centres. All implants had a diameter of 4.0 mm or 4.5 mm. Mandibles were vertically augmented with inter-positional equine bone blocks and resorbable barriers. Implants were placed 4 months after the inter-positional grafting. Maxillary sinuses were augmented with particulated porcine bone via a lateral window covered with resorbable barriers, and implants were placed simultaneously. Implants were not submerged and were loaded after 4 months with provisional screw-retained reinforced acrylic restorations replaced after another 4 months by definitive screw-retained metal-composite prostheses. Patients were followed up to 1 year post-loading. Outcome measures were: prosthesis and implant failures, any complication, and peri-implant marginal bone level changes. RESULTS: Three patients dropped out; one from the maxillary augmented group, one from the mandibular augmented group, and one from the maxillary short implant group. In six augmented mandibles (30%) it was not possible to place implants of at least 10.0 mm, so shorter implants were placed instead. In mandibles, one implant from the augmented group failed vs two 4.0 mm implants in two patients from the short implant group. In maxillae, three short implants failed in two patients vs seven long implants in four patients (two long implants and one short implant dropped into the maxillary sinus). Two prostheses on short implants (one mandibular and one maxillary) were placed at a later stage because of implant failures, vs six prostheses (one mandibular and five maxillary) at augmented sites (one mandibular prosthesis not delivered, three maxillary prostheses delivered with delays, one not delivered, and one failed) at augmented sites. In particular, three patients in the augmented group (one mandible and two maxillae) were not wearing a prosthesis. There were no statistically significant differences in implant failures (P (chi-square test) = 0.693; difference in proportion = 0.03; CI 95% -0.11 to 0.17) or prostheses failures (P (chi-square test) = 0.126; difference in proportion = 0.10; CI 95% -0.03 to 0.24). At mandibular sites, nine augmented patients were affected by complications vs two patients treated with short implants (P (chi-square test) = 0.01; difference in proportion = 0.37; CI 95% 0.11 to 0.63), the difference being statistically significant. No significant differences were found for maxillae: nine sinus-lifted patients vs four short implant patients were affected by complications (P (chi-square test) = 0.091; difference in proportion = 0.25; CI 95% -0.03 to 0.53). At 1-year post-loading, average peri-implant bone loss was 0.51 mm at 4 mm long mandibular implants, 0.77 mm at 10 mm or longer mandibular implants, 0.63 mm at short maxillary implants and 0.72 mm at long maxillary implants. The difference was statistically significant in mandibles (mean difference -0.26 mm, 95% CI -0.39 to -0.13, P (ANCOVA) < 0.001), but not in maxillae (mean difference -0.09 mm, 95% CI -0.24 to 0.05, P (ANCOVA) = 0.196). CONCLUSIONS: One year after loading 4.0 mm long implants achieved similar results, if not better, than longer implants in augmented jaws, but were affected by fewer complications. Short implants might be a preferable choice over bone augmentation, especially in mandibles, since the treatment is less invasive, faster, cheaper, and associated with less morbidity. However, 5 to 10 years post-loading data are necessary before making reliable recommendations.

Immediate, early (6 weeks) and delayed loading (3 months) of single, partial and full fixed implant supported prostheses: 1-year post-loading data from a multicentre randomised controlled trial.

PURPOSE: To compare the clinical outcome of single, partial and complete fixed implant supported prostheses immediately loaded (within 48 h), early loaded at 6 weeks, and conventionally loaded at 3 months (delayed loading). MATERIALS AND METHODS: A total of 54 patients (18 requiring single implants, 18 partial fixed prostheses, and 18 total fixed cross-arch prostheses) were randomised in equal numbers at two private practices to immediate loading (18 patients), early loading (18 patients), and conventional loading (18 patients) according to a parallel group design with three arms. To be immediately or early loaded, implants had to be inserted with a torque superior to 40 Ncm. Implants were initially loaded with provisional prostheses, replaced after 4 months by definitive ones. Outcome measures were prosthesis and implant failures, complications and peri-implant marginal bone levels. RESULTS: Two conventionally loaded patients rehabilitated with cross-arch fixed total prostheses dropped-out up to 1 year post-loading. No implant or prosthesis failed and three complications occurred, one in each loading group. Peri-implant marginal bone loss was 0.19 ± 0.44 mm at immediately loaded implants, 0.18 ± 0.66 mm at early loaded implants and 0.25 ± 0.28 mm at conventional loaded implants. There were no statistically significant differences in complications (P = 1.000) and bone loss (P = 0.806) between the three loading strategies. CONCLUSIONS: All loading strategies were highly successful and no differences could be observed for implant survival and complications when loading implants immediately, early or conventionally.

The role of dental implant abutment design on the aesthetic outcome: preliminary 3-month post-loading results from a multicentre split-mouth randomised controlled trial comparing two different abutment designs.

PURPOSE: To evaluate whether there are aesthetic and clinical benefits to using a newly designed abutment (Curvomax), over a conventional control abutment (GingiHue). MATERIALS AND METHODS: A total of 49 patients, who required at least two implants, had two sites randomised according to a split-mouth design to receive one abutment of each type at seven different centres. The time of loading (immediate, early or delayed) and of prosthesis (provisional crowns of fixed prosthesis) was decided by the clinicians, but they had to restore both implants in a similar way. Provisional prostheses were replaced by definitive ones 3 months after initial loading, when the follow-up for the initial part of this study was completed. Outcome measures were: prosthesis failures, implant failures, complications, pink esthetic score (PES), peri-implant marginal bone level changes, and patient preference. RESULTS: In total, 49 Curvomax and 49 GingiHue abutments were delivered. Two patients dropped out. No implant failure, prosthesis failure or complication was reported. There were no differences at 3 months post-loading for PES (difference = -0.15, 95% CI -0.55 to 0.25; P (paired t test) = 0.443) and marginal bone level changes (difference = -0.02 mm, 95% CI -0.20 to 0.16; P (paired t test) = 0.817). The majority of the patients (30) had no preference regarding the two abutment designs; 11 patients preferred the Curvomax, while five patients preferred the GingiHue abutments (P (McNemar test) = 0.210). CONCLUSIONS: The preliminary results of the comparison between two different abutment designs did not disclose any statistically significant differences between the evaluated abutments. However the large number of missing radiographs and clinical pictures casts doubt on the reliability of the results. Longer follow-ups of wider patient populations are needed to better understand whether there is an effective advantage with one of the two abutment designs.

Short implants as an alternative to crestal sinus lift: a 3-year multicentre randomised controlled trial.

PURPOSE: To evaluate the efficacy of short (5 or 6 mm long) dental implants vs 10 mm or longer implants placed in crestally lifted sinuses. MATERIALS AND METHODS: Twenty partially edentulous patients with 5 to 7 mm of residual crestal height and at least 7 mm thickness below the maxillary sinuses as measured on computed tomography scans were randomised according to a parallel group design to receive either one to two 5 or 6 mm long implants (10 patients) or 10 mm long implants (10 patients) after crestal sinus lifting and grafting with anorganic bovine bone. Implants were left to heal submerged for 4 months and were loaded with reinforced acrylic provisional prostheses, replaced, after 4 months, by definitive provisionally cemented or screw-retained metal-ceramic or metal-composite prostheses. Outcome measures were: prosthesis and implant failures, any complications, radiographic peri-implant marginal bone level changes, and patient's satisfaction assessed by blinded assessors, when possible. All patients were followed up to 3 years after loading. RESULTS: Two patients from the augmented group dropped out after the 1-year follow-up. No implant or prosthesis failure occurred. One short implant patient was affected by two complications vs one complication in the long implant group. There was no difference for patients experiencing complications between the two groups (difference in proportions = -0.03 %; 95%CI: -0.32 to 0.27; P = 1.000). Short implants lost 0.89 ± 0.25 mm and long implants lost 1.08 ± 0.29 mm of peri-implant marginal bone 3 years after loading, the difference between the two groups being not statistically significant (difference = -0.19 mm; 95%CI: -0.46 to 0.09; P = 0.165). All patients were fully or partially satisfied with function and fully satisfied with aesthetics. CONCLUSIONS: Both techniques achieved excellent results and no differences were observed between prostheses supported by one to two 5 or 6 mm long implants vs 10 mm long in posterior atrophic maxillae up to 3 years after loading; therefore it is up to clinicians to decide which procedure to use, although longer follow-ups with larger patient populations are needed to better understand if one of these procedures could be more effective in the long-term. Conflict of interest statement: this study was partially supported by Zimmer Biomet. However, data property belonged to the authors, and by no means did the manufacturer interfere with the conduct of the trial or the publication of its results.

Endodontic retreatment vs dental implants of teeth with an uncertain endodontic prognosis: 1-year results from a randomised controlled trial.

PURPOSE: To ascertain whether in the presence of a previously endodontically treated tooth with a periapical pathology and/or symptoms and an uncertain prognosis, it is better to endodontically retreat it or to replace the tooth with a single implant-supported crown. MATERIALS AND METHODS: Forty patients requiring the treatment of a previously endodontically treated tooth, with a periapical pathology and/or symptoms of endodontic origin and an uncertain prognosis, as judged by the recruiting investigators, were randomly allocated to endodontic retreatment (endo group; 20 patients) or tooth extraction and replacement with an implant-supported crown (implant group; 20 patients) according to a parallel group design at two different centres. Patients were followed to 1 year after completion of the treatment. Outcome measures were: failure of the procedure, complications, marginal bone level changes at both teeth and implants, endodontic radiographic success (teeth only), number of patients' visits and days to complete the treatment, patients' chair time, costs, aesthetics assessed using the pink esthetic score (PES) for the soft tissues and the white esthetic score (WES) for the tooth/crown recorded by independent assessors. RESULTS: No patient dropped out and no complications occurred during the entire follow-up; however, one endodontically retreated tooth (5%) and one implant (5%) fractured, the difference for treatment failures being not statistically significant (difference in proportions = 0; 95% CI -0.14 to 0.14; P Fisher's exact test) = 1.000). The mean marginal bone levels at endo retreatment/implant insertion were 2.34 ± 0.88 mm for the endo and 0.23 ± 0.35 mm for the implant group, which was statistically significantly different (mean difference = 2.11 mm; 95% CI: 1.68 to 2.55; P (t-test) < 0.001). One year after completion of the treatment, teeth lost on average 0.32 ± 0.53 mm and implants 0.48 ± 0.72, the difference not being statistically significant (mean difference = -0.16 mm; 95% CI: -0.58 to 0.27; P (t-test) = 0.457). One year after completion of the endodontic retreatment, of the 13 teeth that originally had a periapical radiolucency, one was lost, six showed complete healing; four a radiographic improvement; and two showed no changes/worsening. Two of the teeth originally without a lesion developed a lesion. There were no statistically significant differences for the number of patients' visits (endo = 5.2 ± 1.8; implant = 5.5 ± 1.1; mean difference = -0.03 95% CI: -1.24 to 0.64; P (t-test) = 0.522). It took significantly more days to complete the implant rehabilitation (endo = 48.9 ± 19.5; implant = 158.5 ± 67.2; mean difference = -109.60; 95% CI: -141.26 to -77.94; P (t-test) < 0.001), but less patients' chair time (endo = 405.5 ± 230.3 min; implant = 260.0 ± 154.6 min; mean difference = 45.50; 95% CI: 19.35 to 271.65; P (t-test) = 0.025). Implant treatment was significantly more expensive (endo = 1195 ± 503.7 €; implant = 1907.5 ± 232.4 €; mean difference = -712.50; 95% CI: -963.59 to -461.41; P (t-test) < 0.001). One year after treatment completion, the mean PES was 10.92 ± 1.93 and 7.07 ± 2.87 and the mean WES was 7.67 ± 1.83 and 7.60 ± 2.32 in the endo group and implant group, respectively. Soft tissues aesthetics (PES) was significantly better at endodontically retreated teeth (mean difference 3.85; 95% CI 1.94 to 5.76; P (t-test) < 0.001) whereas no significant differences were observed for tooth aesthetics (WES) (mean difference 0.07; 95% CI -1.62 to 1.76; P (t-test) = 0.936) between treatments. CONCLUSIONS: The preliminary results suggest that both endodontic retreatment and replacement of previously endodontically treated teeth with persisting pathology and a dubious endodontic prognosis provided similar short-term success rates. Aesthetics of the soft tissues and time needed to complete treatment were in favour of endodontic retreatment, whereas implant rehabilitation required half of the chair time than endodontic retreatment, but was significantly more expensive. Although much larger patient populations and longer follow-ups are needed to fully answer this question, in this scenario the less invasive endodontic retreatment could be the first therapeutic option to be considered.

Two or three machined vs roughened surface dental implants loaded immediately supporting total fixed prostheses: 1-year results from a randomised controlled trial.

PURPOSE: To compare implants with machined vs roughened surfaces placed flapless in totally edentulous jaws and immediately restored with metal-resin screw-retained cross-arch prostheses. Mandibles were rehabilitated with two implants (Fixed-on-2 or Fo2) and maxillae with three implants (Fixed-on-3 or Fo3). MATERIALS AND METHODS: Forty edentulous or to be rendered edentulous patients (20 in the mandible and 20 in the maxilla) were randomised to the machined group (20 patients: 10 mandibles and 10 maxillae) and to the roughened group (20 patients: 10 mandibles and 10 maxillae) according to a parallel group design. To be immediately loaded implants had to be inserted with a minimum torque of 60 Ncm. Outcome measures were prosthesis and implant failures, complications and peri-implant marginal bone level changes evaluated up to 1 year post-loading. RESULTS: Flaps were raised in four patients from the machined group. Four prostheses on machined implants and three on roughened implants were delayed for loading because a sufficient insertion torque was not obtained. There were no dropouts 1 year after loading. Two maxillary machined implants were lost in two patients (difference in proportions = 0.10; 95% CI = -0.03 to 0.23; P (Fisher's exact test) = 0.487); one maxillary Fo3 prosthesis on machined implants and one mandibular Fo2 prosthesis on roughened implants had to be remade (difference in proportions = 0; 95% CI = -0.14 to 0.14; P (Fisher's exact test) = 1.000). Five patients with machined implants had six complications vs seven patients who had eight complications at roughened implants (difference in proportions = -0.10; 95% CI = -0.38 to 0.18; P (Fisher's exact test) = 0.731). There were no statistically significant differences for implant failures, prosthetic failures or complications between groups. There were no statistically significant differences for marginal peri-implant bone levels between the two groups (estimate of the difference = -0.06 mm; 95% CI = -0.23 to 0.10; P (ANCOVA) = 0.445), with both groups losing marginal bone in a statistically significant way (0.35 ± 0.23 mm for machined and 0.42 ± 0.27 mm for roughened surface). CONCLUSIONS: These preliminary results suggest that immediately loaded cross-arch prostheses can be supported by only two mandibular or three maxillary dental implants at least up to 1 year post-loading, independently of the type of implant surface used. Longer follow-ups are needed to understand whether one of the two-implant surfaces is preferable.

Vertical Osseodistraction with a New Intraosseous Alveolar Distractor Prototype for Dental Implant Rehabilitation: A Pilot Study in Dogs.

PURPOSE: To evaluate in dogs a newly developed intraosseous alveolar distractor (Mozo-Grau Alveolar Distractor) for vertical bone augmentation to allow placement of dental implants. MATERIALS AND METHODS: Four dogs had their posterior teeth removed, and sockets were left to heal for 20 weeks. The right and left sides of the posterior mandibles were randomly allocated, according to a split-mouth design, to receive either two distractors, distracting a 32-mm-long bone segment, or two distractors supporting one bony segment 20 mm long and one 8 mm long. Each side of the jaw was treated by a different operator. Eight days after placement, distractors were activated with one complete turn (corresponding to 0.75 mm of vertical distraction) per day for 8 days, followed by a latency period of 10 weeks. Distractors were removed, and seven dental implants of two randomly allocated designs were placed in each dog. Implants were submerged for 2 months, and the dogs were sacrificed. Outcome measures were: success of the augmentation procedure (defined as a vertical gain of at least 5 mm of bone), any complications, implant failure, bone-to-implant contact (BIC), and peri-implant marginal bone level changes. RESULTS: One dog was withdrawn because of a mandible fracture. Eight complications occurred, and six osseodistractors were lost, but no implant failed. Only two segments in one dog achieved a vertical bone gain of at least 5 mm. The mean radiographic vertical bone gain was 2.28 mm, whereas the mean histologic vertical bone gain was 3.16 mm. Histologically, all the implants were osseointegrated. The mean BIC for implants placed in new distracted bone was 34.78% ± 11.60% and 35.66% ± 8.84% for those placed in native bone. The mean peri-implant marginal bone level loss was 0.56 ± 0.54 mm. CONCLUSION: It is possible to achieve vertical augmentation using intraosseous alveolar distractors to allow successful implantation of dental implants; however, the technique still requires surgical refinements and a dedicated training of the surgeons before being applied to humans.