Influence of keratinized mucosa width on the resolution of peri-implant mucositis: A prospective cohort study.

BACKGROUND: The prevalence of peri-implant diseases, driven by biofilm accumulation and influenced by factors such as the width of keratinized mucosa (KM), underscores the need for understanding their etiology and management. PURPOSE: To evaluate the association between the KM width and the clinical resolution of peri-implant mucositis after mechanical therapy. MATERIALS AND METHODS: Patients with an implant diagnosed with peri-implant mucositis were allocated to two groups: wide band of KM (WKM ≥ 2 mm) and narrow/no band of KM (NKM < 2 mm). Data and submucosa biofilm were collected at baseline and at 8, 12, and 24 weeks after nonsurgical therapy. A Brunner-Langer model was estimated for longitudinal data to evaluate and compare changes in any clinical parameter throughout follow-up between both groups. Furthermore, the microbial profiles were evaluated by 16S rRNA gene sequencing. RESULTS: A total of 38 implants were analyzed. At 24 weeks, bleeding on probing was substantially reduced in both groups, reaching statistical significance (p < 0.001). Treatment resulted in 23.9% less effective in achieving success for NKM. As such, NKM reduced the odds of disease resolution by 80% compared to WKM. The rest of the explored clinical parameters yielded more favorable outcomes for WKM versus NKM. Neither the alpha nor the beta diversity of the microbial profiles were significantly modulated by KM. CONCLUSIONS: KM width influences the clinical resolution of peri-implant mucositis after mechanical therapy (https://clinicaltrials.gov/study/NCT04874467?cond=keratinized%20mucosa&rank=8, NCT04874467, 04/30/2021).

Influence of the level of compliance with preventive maintenance therapy upon the prevalence of peri-implant diseases.

BACKGROUND: A study was made to evaluate peri-implant conditions in compliers and erratic compliers with peri-implant maintenance therapy (PIMT), and to assess the role of site-specific confounders. METHODS: Erratic PIMT compliers (EC) were defined as presenting attendance < 2×/year, while regular compliers (RC) attended ≥ 2×/year. Generalized estimating equations (GEE) were employed to perform a multivariable multilevel analysis in which the peri-implant condition was established as dependent variable. RESULTS: Overall, 86 non-smoker patients (42 RC and 44 EC) attending the Department of Periodontology of the Universitat Internacional de Catalunya were recruited consecutively on a cross-sectional basis. The mean period of loading was 9.5 year. An implant placed in an erratic patient has 88% higher probability of presenting peri-implant diseases versus RC. Furthermore, the probability of diagnosis of peri-implantitis was significantly higher in EC versus RC (odds ratio [OR] 5.26; p = 0.009). Among other factors, history of periodontitis, non-hygienic prosthesis, period of implant loading, and modified plaque index (mPI) at implant level were shown to significantly increase the risk of peri-implantitis diagnosis. Although not associated with peri-implantitis diagnosis risk, keratinized mucosa (KM) width, and vestibular depth (VD) were significantly associated to plaque accumulation (mPI). CONCLUSIONS: Compliance with PIMT was found to be significantly associated with peri-implant condition. In this sense, attending PIMT < 2×/year may be ineffective to prevent peri-implantitis.

Proximal Periodontal Support Adjacent to Untreated Peri-implantitis Lesions: A Cross-Sectional Analysis.

PURPOSE: To assess site-related features of peri-implantitis occurring adjacent to teeth and its association with the proximal periodontal bone level. MATERIALS AND METHODS: Periapical radiographs were collected from partially edentulous patients exhibiting peri-implantitis adjacent to teeth. The following variables were quantified: intrabony defect width (DW), implant marginal bone loss (MBLi), tooth marginal bone loss (MBLt), implant-tooth distance (ITd), intrabony defect angulation (DA), adjacent periodontal bone peak height (ABPh), and implant-tooth angulation (ITa). A correlation matrix using the Spearman correlation coefficient was created to explore the dependence of these variables. Univariate linear regression analysis was carried out by means of generalized estimating equations (GEE), using MBLt as dependent variable. RESULTS: Overall, 61 patients and 84 implants were included in this study, consisting of a total of 105 implant sites facing adjacent teeth. This resulted in 515 linear and 194 angular measurements. A total of 11 different statistically significant associations were demonstrated between the different variables analyzed. Moreover, the univariate regression analysis revealed significant positive associations between MBLt and MBLi (P = .013) and between MBLt and periodontitis (PD) (P = .014). These associations were confirmed in the multivariate model. CONCLUSIONS: Teeth adjacent to untreated peri-implantitis lesions are associated with proximal loss of periodontal support. This finding is more remarkable in scenarios that display short implant-tooth distance.

Techniques on vertical ridge augmentation: Indications and effectiveness.

Vertical ridge augmentation techniques have been advocated to enable restoring function and esthetics by means of implant-supported rehabilitation. There are three major modalities. The first is guided bone regeneration, based on the principle of compartmentalization by means of using a barrier membrane, which has been demonstrated to be technically demanding with regard to soft tissue management. This requisite is also applicable in the case of the second modality of bone block grafts. Nonetheless, space creation and maintenance are provided by the solid nature of the graft. The third modality of distraction osteogenesis is also a valid and faster approach. Nonetheless, owing to this technique's inherent shortcomings, this method is currently deprecated. The purpose of this review is to shed light on the state-of-the-art of the different modalities described for vertical ridge augmentation, including the indications, the step-by-step approach, and the effectiveness.

Strategies for implant surface decontamination in peri-implantitis therapy.

Peri-implantitis is an infectious disease that leads to progressive bone loss. Surgical therapy has been advocated as a way of halting its progression and re-establishing peri-implant health. One of the most challenging but crucial tasks in the management of peri-implantitis is biofilm removal to achieve reosseointegration and promote the reduction of peri-implant pockets. A wide variety of strategies have been used for implant surface decontamination. Mechanical means have been demonstrated to be effective in eliminating calculus deposits and residual debris; however, the presence of undercuts and the grooves and porosities along the roughened implant surface make it difficult to achieve an aseptic surface. In conjunction with mechanical measures, use of chemical adjuncts has been advocated to dilute bacterial concentrations, destroy the bacteria's organic components and eliminate endotoxins. Pharmacological adjuncts have also been recommended to diminish the bacterial load. Other strategies, such as use of lasers, implantoplasty and electrolysis, have been suggested for implant surface decontamination to promote predictable clinical and radiographic outcomes.

Impact of smoking on peri-implant bleeding on probing.

BACKGROUND: Studies around natural dentition demonstrated that smoking can reduce the tendency of inflamed tissue to bleed upon probing after controlling for possible confounders. In addition, previous research suggested that smokers may present alterations of the peri-implant microbiome. AIM: This study aimed at investigating the impact of smoking on: (1) peri-implant bleeding on probing (BOP; primary objective); (2) the association between BOP/bone loss and BOP/visible gingival inflammation; (3) peri-implant microbiome. METHODS: Partially edentulous patients with implants restored with a single crowns were included in this study. Subjects were either smokers (≥1 cigarettes per day) or nonsmokers (never smokers). The primary outcome of this cross-sectional study was BOP and secondary outcomes included: Probing pocket depth (PPD), Modified gingival Index (mGI) and Progressive Marginal Bone Loss. In addition, microbial profiles of the subjects were assessed through sequencing of the 16S rRNA gene. Univariate and multilevel multivariate analyses by means of Generalized Estimating Equations were conducted to analyze the association between smoking and peri-implant BOP. RESULTS: Overall, 27 nonsmokers and 27 smokers were included and 96.3% and 77.78% of patients presented peri-implant BOP in the nonsmoker and smoker group, respectively (p = 0.046). Smoking was inversely associated with BOP in the multivariate multilevel analysis (OR = 0.356; 95% CI: 0.193-0.660; p = 0.001) whereas a positive correlation was demonstrated for mGI > 0 (OR = 3.289; 95% CI: 2.014-5.371; p < 0.001); PPD (OR = 1.692; 95% CI: 0.263-0.883; p = 0.039) and gender (OR = 2.323; 95% CI: 1.310-4.120 p = 0.004). A decrease of BOP sensitivity in detecting visible gingival inflammation (mGI > 0) was observed in smokers. Besides, taxonomic and changes in diversity regarding the peri-implant microbiota were detected comparing the two groups. Significantly higher richness of the microbiota was demonstrated in the smoker group when implants affected by peri-implantitis were compared to either healthy implants or implants presenting mucositis. CONCLUSIONS: Smoking is a potential modifier of BOP and peri-implant microbiota.

Dimensional changes in free epithelialized gingival/mucosal grafts at tooth and implant sites: A prospective cohort study.

BACKGROUND: A study was made of the dimensional changes in free epithelialized gingival/mucosal grafts (FEGs) used to augment keratinized tissue (KT) at tooth and implant sites, and of the confounders influencing the dynamic changes over 6 months of follow-up. METHODS: A prospective cohort interventional study was made of implant and tooth sites needing KT augmentation by means of an apically positioned flap and FEG. Six intraoperative variables were recorded at baseline (T0). In addition, graft width (GW), graft length (GL), and graft dimension (GD) were assessed at 3 weeks (T1), 3 months (T2), and 6 months of follow-up (T3). Univariate and multivariate analyses were performed to explore associations between the demographic and intraoperative variables and the outcomes over the study period. RESULTS: Based upon an a priori power sample size calculation, a total of 56 consecutive patients were recruited, of which 52 were available for assessment. A total of 73 graft units were included in 122 sites. At T3, the mean change in GD in FEG was 40.21%. In particular, the mean changes in GL and GW were 12.13% and 33.06%, respectively. Statistically significant changes in GD were recorded from T0 to T1 (P < 0.0005) and from T1 to T2 (P < 0.0005), but not from T2 to T3 (P = 0.13). The change in GD at T3 was 33.26% at tooth and 43.11% at implant site level (P = 0.01). Age and GW assessed at T0 proved to be related to the changes in GD and GW in the univariate and multivariate analyses. The univariate analysis showed the avascular area (AA) to be related to the changes in GD and GW at the implant sites, whereas graft thickness (GT) was associated to changes in GD and GW at the tooth sites in the univariate and multivariate analyses. CONCLUSION: Free epithelialized grafts are exposed to dimensional changes that result in a reduction of approximately 40% of the original graft dimension-the changes being approximately 10% greater at the implant sites than at the tooth sites (NCT04410614).

Resolution of peri-implantitis by means of implantoplasty as adjunct to surgical therapy: A retrospective study.

BACKGROUND: There is a paucity of data on the effectiveness of implantoplasty as adjunct to the surgical management of peri-implantitis. The purpose of this study was to evaluate the resolution of peri-implantitis by means of implantoplasty as adjunct to surgical resective (RES) and reconstructive (REC) therapies and supportive maintenance. METHODS: Patients that underwent surgical therapy to manage peri-implantitis with a follow-up of ≥12 months and enrolled in a regular peri-implant supportive care were recruited. RES group consisted of two interventions that included osseous recontouring and apically position flap (APF) and soft tissue conditioning (STC). REC was performed in the infra-osseous compartment of combined defects. Implant survival rate was recorded. Clinical and radiographic parameters were evaluated to define a "dogmatic" (case definition #1) and a "flexible" (case definition #2) therapeutic success. Univariate and multivariate multilevel backward logistic regression were applied for statistical analysis. RESULTS: Overall, 43 patients (nimplants  = 135) were retrospectively assessed. Mean observational period was ∼24 months. Implant survival rate was 97.8%, being significantly higher for APF, STC, and APF + STC (RES) when compared with REC (P = 0.01) therapy, in particular for advanced lesions (>50% of bone loss). The overall therapeutic success rate at implant-level was 66% and 79.5% for case definition #1 and #2, respectively. APF group displayed more efficient disease resolution when considered success definition #1 (72%). Contrarily, when the data were adhered to success definition #2, STC group showed a slightly higher disease resolution rate (87%). For RES group, location, favoring anterior (P = 0.04) and defect type, favoring class II (P = 0.02) displayed statistical significance for therapeutic success. For REC group, implants exhibiting a wider band of keratinized mucosa (KM) demonstrated higher therapeutic success (P = 0.008). CONCLUSION: Implantoplasty as an adjunct to surgical therapy proved effective in terms of disease resolution and implant survival rate. Implant location, defect morphology as well as the buccal width of KM are indicators of therapeutic success.

Local hormones and growth factors to enhance orthodontic tooth movement: A systematic review of animal studies.

BACKGROUND: Prolonged treatment times are the main reason capable of affecting patient compliance with orthodontic treatment. OBJECTIVES: A systematic review was made to determine whether the local administration of hormones and growth factors effectively enhances orthodontic tooth movement, and to identify possible adverse effects in animal studies. MATERIALS AND METHODS: Five databases (PubMed, Scopus, EMBASE, Web of Science and Cochrane Library) were checked for experimental studies reporting one of the following outcomes: orthodontic tooth movement, histological outcomes and side effects. After data extraction, orthodontic tooth movement linked to adjunctive substances was analysed using forest plots. The risk of bias and the quality of evidence were determined with the SYRCLE tool and the GRADE tool, respectively. RESULTS: Twenty-four studies were included in the systematic review. On a specific dose level, epidermal growth factor + liposomes, fibroblast growth factor and prostaglandin E2  + Ca were supported by a moderate level of evidence and rated as highly effective in increasing tooth movement in animal models. Likewise, there was histological evidence of increased bone remodelling after the administration of these substances. Other compounds were supported by a low to very low level of evidence. CONCLUSIONS: Hormones and growth factors may have a relevant impact upon orthodontic tooth movement rate. In specific formulations, prostaglandin E2 , fibroblast growth factor and epidermal growth factor showed promising results.

Significance of probing for monitoring peri-implant diseases.

Peri-implant diseases at implant sites represent the most considerable concern for many dental clinicians nowadays due to their detrimental effect on implant longevity. Preventive measures include patient education and motivation, supportive peri-implant therapy and routine assessment of the hard and soft tissues. Nevertheless, the reliability of clinical parameters to monitor peri-implant conditions is subject to debate. As such, the primary purpose of the present review was to gain further insight into the diagnostic accuracy of probing as a clinical tool to monitor dental implants and assist clinicians in preventing peri-implant diseases. Studies have recommended periodic probing to monitor the condition of the peri-implant tissues. Increased probing pocket depth, profuse bleeding on probing and suppuration at implants are clinical signs that have been associated with peri-implantitis; thus, if these clinical parameters are present, radiographic assessment is encouraged to make a definitive diagnosis considering potential inaccuracies related to local and/or systemic factors identified in the present review.

Hard tissue dimensional changes following implant removal due to peri-implantitis: A retrospective study.

BACKGROUND: The current evidence regarding the alterations experienced by the alveolar ridge (hard tissue changes) after implant removal due to peri-implantitis is limited. PURPOSE: To assess the hard tissue dimensional changes following implant removal due to peri-implantitis. MATERIAL AND METHODS: Clinical records were examined to identify patients with implants that had to be removed due to a hopeless prognosis secondary to peri-implantitis due to expendability of peri-implantitis implants for functional reasons. Patients with preoperative and postoperative cone-beam computed tomography (CBCT) scans were included. Patient-related, implant-related, and surgery-related factors were assessed based on the clinical records. Linear measurements were made to evaluate the influence of bone plate thickness (BPT), ridge width (RW), and ridge height (RH) at various levels upon the outcome of implant removal. A descriptive statistical analysis of the quantitative and qualitative variables was performed. Correlations of the variables with the primary outcome (dimensional changes) were tested using univariate and multivariate analyses (multinomial random intercept mixed model linear regressions). RESULTS: A total of 26 patients (nimplants = 79) met the eligibility criteria. The mean decrease in RW at 1 and 3 mm below the crest was 11.3% and 4.4%, respectively (P < 0.001). Buccal and lingual RH was significantly reduced by 2.2% and 6.3%, respectively (P < 0.001). Few patient-related, implant-related, and surgery-related factors appeared to have an impact upon the hard tissue dimensional changes. Bone regeneration simultaneous to implant removal minimized the dimensional changes of the ridge both vertically (5% lesser buccal RH reduction) and horizontally (12% lesser RW reduction) when compared with spontaneous healing. The use of a reverse-torque removal kit seemed to be critical in limiting the dimensional changes of the ridge. CONCLUSIONS: Minimal hard tissue changes can be expected following implant removal due to peri-implantitis. Simultaneous bone regeneration procedures and the use of a removal kit may considerably reduce the impact upon the dimensional changes (NCT04534361).

Compliance with supportive periodontal/peri-implant therapy: A systematic review.

AIM: The present systematic review aimed at assessing the degree of compliance with supportive periodontal/peri-implant therapy as well as identifying patient-related factors that could potentially play a role on patient compliance. METHODS: Electronic and manual literature searches were carried out to assess patient compliance during maintenance. Main outcomes were compliance definition, degree of compliance and patient-related factors. Owing to the heterogeneity of the data reported across the studies, descriptive statistics were performed to shed light on compliance rate and the patient-related factors. RESULTS: A total of 39 articles were included. No consensus regarding the definition of "compliance" was found in the analysed literature. The percentage of fully compliers and non-compliers ranged between 3.3%-86.8% and 1.69%-64.4%, respectively. Smoking habit and history of periodontal disease were found to be associated with patients' compliance. Inadequate information/motivation was found as the main patient-reported reason for non-compliance. CONCLUSIONS: Despite the high variability across studies, compliance with the supportive periodontal/peri-implant maintenance therapy was found to be unsatisfactory. Attitudes, psychological traits and construct associated with compliance remain largely unknown, and still, lack of information and motivation are paramount to be addressed during the periodontal/implant therapy to increase patient compliance.

Physics and Histologic Evaluation of Rotary, Ultrasonic, and Sonic Instruments.

Rotary instruments (RIs) are the most commonly used to perform osteotomies in many fields of medicine. Owing to a new interest in performing a minimally invasive surgery, over last fifteen years new devices have been used in oral surgery such as ultrasonic instruments (UIs) and, lately, sonic instruments (SIs). Nowadays, bone preservation and regeneration are paramount in many clinical situations and, consequently, it is crucial to rely upon instruments, which cause the least tissue damage during the surgery. Concerning SIs, there is still few information about workload to be applied and related temperature increases; furthermore, there are no comparative in-vivo studies, which analyze the thermal and mechanical effects on bone. Thus, SIs have been compared with UIs and RIs in terms of heat generation, operating time, accuracy, and tissue damage. Decalcification and sectioning procedure resulted in no significant differences between the applied instruments in terms of bone damage. RIs resulted more efficient than UIs (P < 0.001), but demonstrated low accuracy (NRS 4.9), whereas SIs (P = 0.005) required more time to perform the osteotomy. The maximum temperature increase occurred in the ultrasonic group. Even though SI were the slowest, they have proved to be the most accurate (NRS 8.4) in comparison with UI (NRS 7.6) and RI (NRS 4.9). Within the limit of this study, sonic instruments could be considered a safe alternative to ultrasonic instruments.