Radiographic evaluation of the distance between the restoration margin and the alveolar bone crest in dental implant patients: A retrospective study.

OBJECTIVES: The recently introduced Implant Disease Risk Assessment (IDRA) identifies a restoration margin-alveolar bone crest (RM-AC) distance of less than 1.5 mm as a key risk factor for peri­implant disease among eight major risk factors. This study evaluated the impact of the RM-AC distance on marginal bone loss (MBL) through radiographic analysis. METHODS: This retrospective cross-sectional study included 77 partially edentulous patients (39 females and 38 males, aged 22 to 76 years) with 202 platform-switched conical connection implants, cement-retained, implant-supported fixed restorations, and bone-level implants placed between 2016 and 2021. Dental implants were followed for least 6 to 36 months at follow up functional loading. Study participants were categorized into Group A (RM-AC distance ≤ 1.5 mm, n = 69) and Group B (RM-AC distance > 1.5 mm, n = 133). Twelve patients in Group B and five patients in Group A had no history of periodontal disease. The MBL was measured radiographically from the most coronal point of the implant shoulder to the alveolar bone, and the RM-AC distance was measured from the restoration margin to the alveolar crest. Multinomial logistic regression analysis was used for statistical evaluation. RESULTS: The incidence of MBL in Group A was statistically significant and 3.42 times higher than that in Group B. The rate of MBL in periodontitis Stage 4 was found to be 26.31 times higher than that in periodontitis Stage 2. The incidence of MBL was 6.097 and 5.02 times higher with increasing implant diameter and length, respectively. CONCLUSION: This study conclusively demonstrates that RM-AC distance ≤ 1.5 significantly increases the risk of MBL, particularly in patients with a history of periodontal disease. CLINICAL SIGNIFICANCE: This study highlights the critical role of maintaining an RM-AC distance greater than 1.5 mm in the prevention of MBL, particularly in patients with a history of periodontal disease. Since implant diameter and length have a significant impact on the risk of MBL, it emphasizes that implant demographics should also be carefully evaluated.

Clinical outcomes of 3-5 years follow-up of immediate implant placement in posterior teeth: a prospective study.

BACKGROUND: Immediate implant placement in posterior teeth has become popular in recent years. However, only a few studies focused on evaluating the long-term success of immediate implant placement. PURPOSE: To analyze the clinical outcomes of immediate implant placement in the posterior region with conventional loading with 3-5 years follow-up following the International Congress of Oral Implantologists (ICOI) Pisa Consensus Conference. METHOD: The study was done in 25 bone-level implants (Straumann® SLActive® bone level tapered implant, Straumann®, Basel, Switzerland) in 19 patients who underwent immediate implant placement in a posterior tooth with conventional loading with 3-5 years follow-up. The overall success and survival of these placements were evaluated following the International Congress of Oral Implantologists (ICOI) Pisa Consensus Conference using chart records, clinical examination, radiographic evaluation, and outcomes measurement. Patient satisfaction was evaluated by using a numeric rating scale. The biological and technical status, modified Pink Esthetic Score (mPES), complications, and marginal bone change were also evaluated. The analysis was done using SPSS version 21 (SPSS Inc., Chicago, IL, USA). The data were analyzed using a paired samples t-test. RESULTS: It was found that 24 out of the 25 (96%) dental implants survived for an average of 57 ± 8.07 months. All of the 24 surviving dental implants were considered an operational success. The average mPES was 9.75 ± 0.44. The major prosthetic complications seen were: (1) proximal contact loss (41.67%), (2) loosening of the screw (8.33%), and (3) cement debonding (4.17%). CONCLUSIONS: Immediate implant placement in a posterior tooth with conventional loading yields a predictable result with some complications. The most prominent complications were proximal contact loss, followed by loosening of the screw and cement debonding. The implant survival rate was 96% at a mean time follow-up of 4 years and 9 months.

Radiographic bone loss around dental implants: a large-cohort, long-term follow-up revealing prevalence and predictive factors.

OBJECTIVE: This retrospective study analyzed radiographic bone levels of 10,871 dental implants in a cohort of 4,247 patients over a 22-year period. The objectives of the study were to assess and explore risk factors associated with the radiographic bone level of dental implants. METHOD AND MATERIALS: A longitudinal observational cohort study based on data collected from 1995 to 2019 was conducted on implants placed by a single periodontist. Inclusion criteria included both partially and fully edentulous sites. Exclusion criteria were patients who were considered ASA 3 or greater. Information on medical and dental status prior to implant placement such as diabetes and smoking were included in the analysis. Implant factors such as the implant characteristics (length and diameter) and surgical site were recorded. The outcome assessed was the prevalence of bone loss around implants and any associative factors related to the bone loss. RESULTS: Overall, dental implants lost an average of 0.05 ± 0.38 mm of bone 2 to 3 years after placement and 0.21 ± 0.64 mm 8 years after placement. The soft tissue condition was evaluated using the Implant Mucosal Index (IMI), and bone loss around dental implants was significantly higher when bleeding on probing was multi-point and moderate, multi-point and profuse, and when infection with suppuration was recorded. The mean difference in bone level between smokers and nonsmokers was 0.26 mm (P < .01) over a 4-year period. A mean difference of 0.10 mm (P = .04) in bone loss over 4 years was found between those with an autoimmune disease compared to those without. The diameter of the implant and immediate loading of the dental implant did not influence the radiographic bone levels over time. CONCLUSIONS: This large dataset of dental implants highlights predictive risk factors for bone loss around dental implants and the impact these risk factors have on the implant bone level. Consideration of these risk factors by both the dental team and the patient prior to dental implant placement will promote success of the treatment.

[Risk factors of perioperative hypertension in dental implant surgeries with bone augmentation].

OBJECTIVE: To investigate the characteristics and risk factors of perioperative hypertension during dental implant surgeries with bone augmentation. METHODS: A retrospective cohort study was conducted. Seven hundred and twenty-eight cases underwent dental implant placement and bone augmentation in Peking University School and Hospital of Stomatology from September 2021 to August 2022 were recruited in this study according to the inclusion and exclusion criteria. They were divided into different groups according to the exposure factors which were gender, age, surgical time, and surgical approach. The correlation between perioperative hypertension and the exposure factors was analyzed. RESULTS: The average systolic blood pressure variability was 9.93%±6.63% (maximum 50.41%), the average diastolic blood pressure variability was 12.45%±8.79% (maximum 68.75%), and the average mean arterial pressure variability was 10.02%±6.61% (maximum 49.48%). The incidence rate of perioperative hypertension was 26.77%. Male, age ≥ 60 years, and surgical time > 60 minutes were risk factors for perioperative hypertension (P < 0.05), and the relative risks (95%CI) were 1.74 (1.21-2.50), 2.35 (1.54-3.58), and 1.65 (1.15-2.38), respectively. There was no significant difference in the incidence of perioperative hypertension among the guided bone regeneration, sinus floor elevation with transalveolar approach, and sinus floor elevation with lateral window approach (P>0.05). However, the risk factors varied according to bone augmentation approaches. For the patients underwent guided bone rege-neration, the risk factors for perioperative hypertension included male, age ≥ 60 years, and surgical time > 60 minutes (P < 0.05). For the patients underwent maxillary sinus lift with transalveolar approach, the risk factor for perioperative hypertension was age ≥60 years (P < 0.05). For the patients underwent maxillary sinus lift with lateral window approach, male, age ≥60 years, and surgical time >60 minutes were not risk factors for perioperative hypertension (P>0.05). CONCLUSION: There was a certain risk of perioperative hypertension in oral implantation with bone augmentation. The influence of male, age ≥60 years and surgical time > 60 minutes on perioperative hypertension was related to the approach of bone augmentation.

Clinical outcomes and risk factor analysis of dental implants inserted with lateral maxillary sinus floor augmentation: A 3- to 8-year retrospective study.

AIM: To evaluate the 3- to 8-year outcomes of dental implants placed with lateral sinus floor augmentation (LSFA) and to identify factors affecting implant survival. MATERIALS AND METHODS: This retrospective study was performed by screening all implants placed with LSFA procedures, which were conducted between January 2012 and December 2016. Subantral bone gain (SABG) and apical bone height (ABH) were assessed using panoramic radiographs. The cumulative survival rate of implants was analysed using life-table analysis and Kaplan-Meier survival curves. The influential risk factors affecting survival were assessed using univariate log-rank tests and multivariable mixture cure rate model. Implant complications were recorded. RESULTS: Based on the established criteria, a total of 449 patients (760 implants) were included in this study. In the 3- to 8-year follow-up (mean ± SD, 5.81 ± 1.33 years), 15 implants in 14 patients failed, with a CRS of 96.81% on an implant basis and 95.07% on a patient basis. A history of periodontitis and poor compliance with supportive periodontal treatment was associated with a significantly higher risk of implant failure at both implant and patient levels. Significant decreases in ABH occurred during each yearly interval except for 3 years. A similar trend has been observed for SABG at 1, 2, 6 and 8 years. The total complication rate was 31.84% on implant basis, with peri-implant mucositis (21.58%) being the most frequent biologic complication and porcelain cracking (5.00%) being the most common technical complication. CONCLUSIONS: Implant with LSFA is a reliable treatment option in atrophic maxilla. A history of periodontitis without regular supportive periodontal treatment was identified as a predictor for implant failure. Slight but significant shrinkage of vertically augmented bone can be observed after implant placement.

How do the dimensions of peri-implant mucosa affect marginal bone loss in equicrestal and subcrestal position of implants? A 1-year clinical trial.

INTRODUCTION: There is evidence that the apico-coronal implant position and the mucosal phenotype can affect the extent of peri-implant bone loss. This clinical trial analyzes the bone remodeling and marginal bone loss that occur around conical-connection implants placed equicrestally and subcrestally, assessing the effect of the peri-implant soft-tissue phenotype. METHODS: Fifty-one patients received 56 implants of distinct diameters (3.5 mm Ø n = 6; 4.3 mm Ø n = 41; 5 mm Ø n = 9) in the posterior part of the maxilla or mandible. The implants were placed equicrestally, 1 mm subcrestally and >1 mm subcrestally, depending on the initial supracrestal tissue height (STH). After 3 months of non-submerged healing, single metal-ceramic screw-retained implant-supported crowns were placed. Longitudinal measurements of STH, mucosal thickness and keratinized mucosa width (KMW) were made at the time of implant placement (T0), crown placement (T1), and after 3 (T2) and 6 months (T3) of prosthetic loading. At each of these points, a radiographic evaluation of bone remodeling and marginal bone loss was also performed. RESULTS: STH was significantly greater for implants placed >1 mm subcrestally than for those placed 1 mm subcrestally. After 12 months of follow-up, a very significant (p < 0.001) loss of KMW was observed, in addition to a marginal bone loss of 0.08 ± 0.1, 0.15 ± 0.2, and 0.14 ± 0.2 mm in the groups placed equicrestally, 1 mm subcrestally and >1 mm subcrestally, respectively. After the multiple linear regression, marginal bone loss was found to depend primarily on KMW (ß = -0.43), while also being affected by STH (ß = 0.32) and implant diameter (ß = -0.28). CONCLUSIONS: Marginal bone loss may be influenced by the position with respect to the bone crest, as well as the KMW, STH, and implant diameter. However, more well-controlled studies are needed to verify these above-mentioned findings with different implant designs and connections.

Immediate repair of bony defects in the posterior mandibular region following removal of a fractured implant: a feasible treatment?

The aim of this study was to assess whether immediate bone reconstruction after removal of a fractured dental implant in the posterior mandible provides a sound base for implant replacement, with a favourable treatment outcome and high patient satisfaction. Eight consecutive patients with a fractured implant neck were included. The implant was removed via osteotomy, following which the site was immediately repaired with a mixture of autogenous bone and bone substitute. After a 4-month healing period, sufficient bone and favourable soft tissue conditions were present, allowing implant placement with adequate primary stability. After a further 3 months, the implants were restored with an all-ceramic restoration. Patient satisfaction, the aesthetic outcome, complications, and postoperative morbidity were assessed using standardized clinical and radiographic examinations up to 5 years after crown placement. No implant failures were observed during the follow-up. Plaque accumulation, the presence of calculus, bleeding tendency, and peri-implant inflammation indices were low, indicating healthy peri-implant conditions. The mean marginal bone level change at the 5-year follow-up was - 0.17 ± 0.46 mm. All patients reported a high level of satisfaction (mean overall score 9.3 ± 0.5). In conclusion, immediate reconstruction of the hard tissue after removal of a fractured dental implant is a viable treatment option. This approach facilitates rehabilitation, reduces morbidity, and leads to favourable aesthetic outcomes.

Bruxism and dental implants: A systematic review and meta-analysis.

BACKGROUND: Overload from bruxism may affect survival of dental implants. OBJECTIVES: To evaluate implant failure and marginal bone loss (MBL) in patients presenting with probable bruxism compared to non-bruxers. The study was registered in PROSPERO (CRD42021238397). METHODS: An electronic search September 2022 in PubMed/Medline, Web of Science and Science Direct was combined with a hand search. Two independent reviewers carried out abstract screening, full-text assessment, quality assessment (National Institutes of Health tool) and data extraction. Only studies that provided information on self-report and clinical examination needed for the diagnosis of at least 'probable' bruxism were included. A pairwise random-effect meta-analysis was carried out. RESULTS: In total 1338 studies were identified, and after screening and full-text assessment 27 studies that presented data on 2105 implants in probable bruxers and 10 264 implants in non-bruxers were included, with 138 and 352 implant failures in respective groups. the meta-analysis showed that implants placed in probable bruxers had a higher risk of failure than in non-bruxers (OR 2.189; 95% CI 1.337, 3.583, p = .002). A meta-regression showed that follow-up time did not affect this OR. Eighteen studies provided general data on MBL but did not report results separated between bruxers and non-bruxers. Therefore, an analysis of MBL was not possible. CONCLUSION: The results of the present systematic review show that implants placed in probable bruxers present a significantly higher risk of failure than implants placed in non-bruxers. This should be considered in treatment planning and management of implant patients.

Management of bleeding during dental implant surgery using a novel implant with an abbreviated drilling protocol: A clinical report.

Coagulopathy is a well-recognized complication in dental surgery in patients who use oral anticoagulants or some dietary supplements. Proper pre-operative diagnosis, medical consultation, timely management, and conservative treatment can decrease the incidence of such complications. Management of bleeding during dental implant surgery commonly involves conventional methods such as discontinuation of anticoagulant use, compression, styptics, and local anesthetic administration containing vasoconstrictors. This clinical report describes the successful management of a patient with a history of coagulopathy who was rehabilitated with complete arch fixed implant-supported prostheses with immediate loading. A novel implant design with a significantly abbreviated single drill protocol for osteotomy preparation was used in an outpatient setting. The novel protocol successfully decreased the overall bleeding and significantly reduced the intraoperative time for the surgical procedure. Additional considerations related to the novel implant design and osteotomy protocol, supplementary applications, and advantages of the protocol are presented in this article.

Correlation between intraosseous thermal change and drilling impulse data during osteotomy within autonomous dental implant robotic system: An in vitro study.

OBJECTIVES: This study aims at examining the correlation of intraosseous temperature change with drilling impulse data during osteotomy and establishing real-time temperature prediction models. MATERIALS AND METHODS: A combination of in vitro bovine rib model and Autonomous Dental Implant Robotic System (ADIR) was set up, in which intraosseous temperature and drilling impulse data were measured using an infrared camera and a six-axis force/torque sensor respectively. A total of 800 drills with different parameters (e.g., drill diameter, drill wear, drilling speed, and thickness of cortical bone) were experimented, along with an independent test set of 200 drills. Pearson correlation analysis was done for linear relationship. Four machining learning (ML) algorithms (e.g., support vector regression [SVR], ridge regression [RR], extreme gradient boosting [XGboost], and artificial neural network [ANN]) were run for building prediction models. RESULTS: By incorporating different parameters, it was found that lower drilling speed, smaller drill diameter, more severe wear, and thicker cortical bone were associated with higher intraosseous temperature changes and longer time exposure and were accompanied with alterations in drilling impulse data. Pearson correlation analysis further identified highly linear correlation between drilling impulse data and thermal changes. Finally, four ML prediction models were established, among which XGboost model showed the best performance with the minimum error measurements in test set. CONCLUSION: The proof-of-concept study highlighted close correlation of drilling impulse data with intraosseous temperature change during osteotomy. The ML prediction models may inspire future improvement on prevention of thermal bone injury and intelligent design of robot-assisted implant surgery.

The influence of vertical ridge augmentation techniques on peri-implant bone loss: A systematic review and meta-analysis.

INTRODUCTION: The primary aim of this systematic review was to investigate and compare the outcomes of different vertical ridge augmentation (VRA) techniques in relation to peri-implant bone loss (PBL), after at least 12 months of functional loading. MATERIAL AND METHODS: The search was conducted to find all the studies about VRA and measurements of PBL with at least 12 months follow-up. Three pairwise meta-analysis (MA) was performed to completely evaluate the outcomes. RESULTS: A total of 42 studies were included, of which 11 were randomized clinical trials (RCTs). RCTs were available only for guided bone regeneration (GBR), onlay, and inlay techniques. The weighted mean estimate (WME) of PBL value was found to be 1.38 mm (95% confidence interval [95% CI]: 1.10-1.66) after a mean follow-up of 41.0 ± 27.8 months. GBR, Inlay, Onlay, osteodistraction, and SBB represented in weight 32.9%, 30.6%, 25.0%, 7.6%, and 3.9%, respectively; and their WME (95% CI) were 1.06 (0.87-1.26) mm, 1.72 (1.00-2.43) mm, 1.31 (0.87-1.75) mm, 1.81 (0.87-1.75) mm, and 0.66 (0.55-0.77) mm, respectively. Among the secondary outcomes, the analysis was conducted for vertical bone gain, healing complication rate, surgical complication rate, implant survival, and success rate. CONCLUSIONS: The primary findings of the meta-analysis, based on the changes between final and baseline values, showed that the peri-implant bone loss could be influenced by the type of intervention but there is a need to evaluate in RCTs the behavior of the peri-implant bone levels after long-term follow-up for all techniques.

Technique-Related Survival Rate and Complications of Zygomatic Implant Placement: A Systematic Review and Meta-Analysis.

PURPOSE: To assess the survival rate (SR) and probability of postoperative complications at both the implant and patient level for each of the four surgical techniques for zygomatic implant (ZI) placement: Brånemark, sinus slot, extrasinus, and extramaxillary. MATERIALS AND METHODS: A systematic literature review and meta-analysis of clinical studies that reported the survival rate and postoperative ZI complications for the rehabilitation of atrophic edentulous maxillae was conducted based on PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) recommendations. Two independent reviewers consulted four databases during the literature search: MEDLINE (PubMed), Google Scholar, Clinicaltrials.gov, and LILACS. Duplicate articles were eliminated. RESULTS: A total of 35 studies were included in the meta-analysis. Subgroup analysis showed that study design (prospective vs retrospective) had no significant impact (P = .10) on the outcomes. The SR was highest for the Brånemark and extrasinus techniques (100%) and lowest for the sinus slot technique (94%; 95% CI = 86% to 102%). The extramaxillary (38%; 95% CI = 1% to 3%) and the Brånemark (29%; 95% CI = 15% to 44%) techniques resulted in the highest occurrence of patient-level complications. Moreover, the extramaxillary technique showed the highest percentage of prothesis-related complications (44%; 95% CI = 27% to 62%). CONCLUSIONS: ZI placement was demonstrated to be a reliable technique for the rehabilitation of severely atrophic maxillae, irrespective of the surgical technique evaluated. Accurate case and surgical protocol selection is of paramount importance to reduce technique-related postoperative complications.

Correlates of Early Dental Implant Failure: A Retrospective Study.

PURPOSE: To examine whether patient-level disease diagnoses, drug treatments, and dental clinical factors are correlates of early implant failure. MATERIALS AND METHODS: This historical, nested case-control study used electronic medical records to retrieve patient-level data on individuals with implant failure occurring up to 6 months after implantation, including demographics, clinical information (number, location, and complicated status of implants), underlying diseases (osteoporosis, diabetes, hypertension, inflammatory bowel disease [IBD], myocardial infarction [MI]), and drug purchases (chemotherapy, bisphosphonates, selective serotonin inhibitors, antihypertensive medications, proton pump inhibitors [PPIs], disease-modifying antirheumatic drugs, corticosteroids, and nonsteroidal anti-inflammatory drugs) among adult members of a large, state-mandated health provider in Israel between 2015 and 2020. Individuals with implant extraction occurring up to 6 months after implantation were matched 1:1 to controls. Univariate and adjusted multivariate conditional logistic regression models were used to examine the odds ratios (ORs) of all dental implant risk factors among the patients. RESULTS: A total of 585 individuals with implant failure (mean age, 53 years [42,62], 51.3% females and 49.7% males) were identified among 29,378 eligible patients. Compared to controls, patients who experienced implant failure (ie, cases) were more likely to have smoked in their lifetime (18% vs 11.5%, P = .009), experienced IBD (1.5% vs 0.02%, P = .059), and consumed PPIs within 6 months of the implant surgery (40.0% vs 32.5%, P = .028). Clinical factors, including the number of implants per person (individuals with two implants, OR = 1.53; individuals with at least four implants, OR = 3.33; P < .01), location of implant (maxilla; OR = 1.59; 95% CI: 1.2-2.04), and smoking (OR = 1.57; 95% CI: 1.09-2.26) were significant correlates of early implant failure among the included cases. Crohn's disease, MI, and osteoporosis were found to be borderline significant correlates of early dental implant failure. CONCLUSIONS: Among the factors examined, the number of implants, the location of implants, and smoking history were significant correlates of early implant failure, while Crohn's disease, MI, and osteoporosis were found to not be significant. Larger patient-level studies are needed to examine the individual and combined effects of diseases, medications, and clinical factors on early implant failure.

Clinical and Radiographic Outcomes of a New Fully Tapered Implant with the One-Abutment One-Time Approach: In-Line Clinical Case Series with a 1-Year Follow-up.

PURPOSE: To evaluate the bone level changes in a new implant design (fully tapered with platform switching) with the one-abutment one-time protocol after 1 year of loading. MATERIALS AND METHODS: Thirty patients received 1 or 2 implants (6-, 8-, or 10-mm length and 3.5-, 3.75-, or 4.5-mm diameter, bone-level design) to replace one or multiple edentulous sites. Only the mesial implant was assessed. Radiographic, clinical, and esthetic results and the survival and success rates were evaluated 1 year after final loading. RESULTS: At 1 year, no peri-implant bone loss was seen in any of the cases. Mean marginal crestal bone loss between surgery and crown placement was 0.19 ± 0.17 mm (P < .0001). Between surgery and the 1-year follow-up, the mean marginal crestal bone loss was 0.25 ± 0.24 mm (P < .0001). The difference in the modified Plaque Index between 1 year of follow-up and crown placement was significant for in the mesial (0.33 ± 0.54 mm; P = .003) and distal surfaces (0.5 ± 0.73 mm; P = .001). The probing pocket depth was statistically significantly deeper at 1 year than at crown placement at the mesial and distal aspects (average depth = 0.75 mm; P < .0005). No statistically significant differences were found for any other clinical or esthetic parameters. The overall survival and success rates after 1 year were 100%. CONCLUSIONS: The fully tapered, deep-thread, platform-switched implant design placed with the one-abutment one-time protocol demonstrated minimal marginal crestal bone loss and crestal bone stability at 1 year of follow-up.

How to Prevent and Manage Postoperative Complications in Maxillary Sinus Augmentation Using the Lateral Approach: A Review.

Maxillary sinus augmentation with a lateral approach is known to present more postoperative complications than other atrophic posterior maxilla treatment modalities because it is more invasive. These complications include infections that occur in the form of chronic or acute sinusitis. According to the literature, the frequency of these complications ranges from 3% to 5%. They can result from an inadequate management of intraoperative complications or from a poor evaluation of maxillary sinus particularities and pathology before the surgery. Therefore, the prevention of postoperative complications lies in the selection of cases that will allow for the identification and evaluation of infectious risk. Only a multidisciplinary approach that includes an implantologist, a rhinologist, and the treating physician will allow this. On the other hand, in infectious complication cases, the intervention of the otorhinolaryngologist (ENT) specialist is necessary. Based on the available literature and the author's experience, the methodology described in this article will allow for the prevention and management of postoperative complications related to this surgical technique.

Survival and complication rates of two dental implant systems supporting fixed restorations: 10-year data of a randomized controlled clinical study.

OBJECTIVES: To compare clinical, radiographic, biological and technical long-term outcomes of two types of dental implants over a period of 10 years. MATERIALS AND METHODS: Ninety-eight implants were placed in 64 patients, randomly allocated to one of two manufacturers (AST and STM). All implants were loaded with fixed restorations. Outcome measures were assessed at implant insertion (Ti), at baseline examination (TL), at 1, 3, 5, 8 and 10 (T10) years. Data analysis included survival, bone level changes, complications and clinical measures. RESULTS: Re-examination was performed in 43 patients (23 AST and 20 STM) at 10 years. The implant level analysis was based on 37 (AST) and 32 (STM) implants. Survival rates of 100% were obtained for both groups. The median changes of the marginal bone levels between baseline and T10 (the primary endpoint) amounted to a loss of 0.07 mm for group AST and a gain of 0.37 mm for group STM (intergroup p = 0.008). Technical complications occurred in 27.0% of the implants in group AST and in 15.6% in group STM. The prevalence of peri-implant mucositis was 29.7% (AST) and 50.1% (STM). The prevalence of peri-implantitis amounted to 0% (AST) and 6.3% (STM). CONCLUSIONS: Irrespective of the implant system used, the survival rates after 10 years were high. Minimal bone level changes were observed, statistically significant but clinically negligible in favor of STM. Technical complications were more frequently encountered in group AST, while group STM had a higher prevalence of peri-implant mucositis.

The Impact of Sinus Floor Elevation Techniques on Sinus Membrane Perforation: A Systematic Review and Network Meta-analysis.

Purpose: To compare the risk of sinus membrane perforation (SMP) among lateral window sinus floor elevation (LSFE) and transcrestal sinus floor elevation (TSFE) techniques in prospective and retrospective studies for patients who underwent sinus augmentation for dental implant placement. Materials and Methods: A database search was conducted to screen the literature published from January 1960 to August 2021. The associations between SMP and surgical techniques as well as other clinical factors were evaluated via network meta-analysis. The impact of SMP on vertical ridge gain and implant survival was also evaluated. Results: Eighty-five studies with 5,551 SFE procedures were included. In LSFE techniques, using rotary burs showed the highest risk of SMP (surface under the cumulative ranking area [SUCRA] = 0.0745). In TSFE techniques, using reamers had the lowest risk of SMP (SUCRA = 0.9444). Increased SMP prevalence was significantly associated with reduced implant survival rate (odds ratio [OR] = 0.45 per 10% increase of SMP rate [95% credible interval (CreI): 0.21, 0.71], P < .001). Conclusions: With the inherent limitations, this network meta-analysis suggested that some techniques within either the LSFE or TSFE group may reduce SMP risk. Additional randomized controlled trials and better assessment of SMP are required to directly compare the risk of SMP between LSFE and TSFE.

10-year Historical Prospective Cohort Study of Calcium Phosphate-Blasted Acid-Etched Titanium Implants Placed in Different Ridges.

Purpose: To evaluate the survival rate and marginal bone level (MBL) of calcium phosphate-blasted acid-etched titanium implants placed in a cohort of patients with different ridges after a follow-up period of at least 10 years. Materials and Methods: A total of 61 patients with a minimum implant follow-up of 10 years were selected for this historical prospective, best clinical practice cohort study. Between 2009 and 2012, 121 titanium implants were placed using a flap, flapless, or postextractive technique. The implant placement timing was performed according to pre-extractive diagnosis and divided into immediate (immediately after tooth extraction with an absence of infection), early (within 2 to 3 months with an acute periapical lesion), delayed (6 to 12 months from extraction with a large periapical infection), or late (> 12 months from extraction with healed edentulous ridges). All implants were loaded after 3 months with provisional and definitive cemented restorations. Periapical radiographs were taken before implant insertion and at 3, 6, 12, 24, 36, 48, 96, and 120 months (T3, T6, T12, T24, T36, T48, T96, and T120, respectively). The MBL was calculated in single blind by an additional examiner. Linear logistic regression was performed to analyze statistically significant differences in relation to different operative variables at all evaluation times. Multilevel mixed logistic regression was made to evaluate the factors associated to MBL at 10 years (T120). Results: After 10 years, 47 patients and 92 implant restorations were analyzed, showing that 88 implants (95.6%) survived and 4 implants (4.4%) failed. The cumulative drop-out rate was 22.1%. Loosening and/or mobility was observed in a total of 9 abutments (9.7%) during the observational time. No other complications were reported. Implants placed with a flapless technique revealed a similar MBL to those placed with a flap technique. No significant differences were observed between the surgical techniques at T96 and T120. Immediate and early implants revealed a more stable MBL than both delayed and late implants up to T48. At longer evaluation times (T96 and T120), the MBL values were not statistically significant (P > .05). Narrower diameter implants (3.5 mm) revealed a higher bone loss when compared to the 4.1-mm- and 5.0-mm-diameters, especially in the first year from implant insertion (from T3 to T12) and at longer follow-up (T36 and T48). After that, the difference was reduced. Multilevel analysis showed that none of these variables appear to significantly influence MBL at 120 months. Conclusions: MBL was not influenced by surgical technique or implant placement timing after 10 years. Maintaining a strict occlusal and hygiene control created the conditions to preserve bone integrity and achieve a high implant survival rate.

Risk assessment of mandibular incisive canal perforation during dental implant surgery in the anterior edentulous mandible: a virtual implant placement study using cone beam computed tomography.

OBJECTIVE: The aim of this study was to evaluate the risk of mandibular incisive canal (MIC) perforation caused by implants placed on cone beam computed tomography (CBCT) images in the edentulous mandibular anterior region. STUDY DESIGN: A total of 1200 dental implants were virtually inserted on 150 eligible CBCT scans. The relationship of different implant sizes with the incidence of MIC perforation and the relationship between crest height and perforation were evaluated. RESULTS: A total of 1200 virtual implant applications were performed on 150 patients. In 87% of cases, MIC was identified. Perforation in 12 and 14 mm implants was significantly higher than in 8- and 10-mm implants (P < .05). Perforation was found to be statistically significantly higher in crest heights that were ≤20 mm than in crest heights >20 mm (P < .05). CONCLUSIONS: Our results showed high perforation rates in the 12- and 14-mm implants and crests heights that were ≤20 mm during implant surgery in the mandibular anterior edentulous region. Perforation of the MIC should be considered a complication of implant surgery in the mandibular anterior region; therefore, CBCT images should be evaluated before implant placement.

The effect of leukocyte- and platelet-rich fibrin on the bone loss and primary stability of implants placed in posterior maxilla: a randomized clinical trial.

PURPOSE: In this study, we investigated the effects of leukocyte- and platelet-rich fibrin (L-PRF) on implant stability and alterations in the marginal bone surrounding posterior maxillary implants. METHODS: This randomized clinical trial was conducted to compare the variable of L-PRF placement around maxillary implants. Resonance frequency analysis (RFA) was used to evaluate the implant stability immediately after surgery and at 1, 2, 4, 6, 8, and 12 weeks after surgery (t0 to t6, respectively). In addition, the amount of marginal bone changes around the implant at t6 was compared with the baseline using periapical radiography. RESULTS: The RFA outcomes were statistically significant within each group (P < 0.001, Eta2 = 0.322); however, in none of the follow-ups and immediately after the surgery, there was a significant difference between the two groups in terms of the implant stability quotient (ISQ) scores (P > 0.05). At t0, the test and control groups' respective mean levels of marginal bone loss around the implants were 0.4836 mm and 0.7343 mm, significantly different from the corresponding values at t6. On the other hand, marginal bone loss around the implant was not significantly different between the two groups in t0 and t6 (P = 0.532). CONCLUSIONS: L-PRF did not improve the RFA outcomes of implants three months after implant placement, and changes in the ISQ values over time were the same in both groups. In addition, L-PRF had no superior effect on the marginal bone loss around the implants. TRIAL REGISTRATION NUMBER: The research was registered in the Iranian Registry of Clinical Trials on 22 December 2020 (No: IRCT20200624047906N1), available at http://www.irct.ir.