Does the surface conditioning of glass and hybrid ceramics with self-etching silane present a bond strength similar to that of conventional bonding? Systematic review and meta-analysis of in vitro studies.

PURPOSE: To evaluate, through in vitro studies, the bond strength of vitreous and hybrid ceramics with self-etching surface treatment compared to conventional treatment. METHODS: This systematic review followed the preferred reporting items for systematic reviews and meta-analyses (PRISMA) and was registered on the open science framework (OSF) platform for in vitro studies. A population, intervention, control, and outcome (PICO) question was formulated: "Does the surface conditioning of glass and hybrid ceramics with self-etching silane present a bond strength similar to that of conventional bonding?". A literature search was carried out in the PubMed, Embase, Web of Science, Cochrane Library, and ProQuest databases until September 2023. The Joanna Briggs Institute (JBI) critical appraisal guidelines for quasi-experimental studies were used for risk assessment of bias. The meta-analysis was based on the inverse variance (IV) method (p < 0.05). RESULTS: A total of 29 in vitro studies published between 2017 and 2022 were included in this systematic review, totaling 1889 ceramic samples. The meta-analysis indicated a significant decrease in the bond strength of HF 4%-5% with silane compared to self-etching (p < 0.05; MD: 0.34; 95% CI: 0.13-0.35; I2 = 3%, p = 0.42), while it indicated that there was no significant difference between self-etching compared to 9%-10% HF with silane (p = 0.92; MD: 0.02; 95% CI: -0.32 to 0.36; I2 = 14%, p = 0.32). CONCLUSION: Self-etching primer presents bond strength that is superior to or similar to conventional surface treatment on glass and hybrid ceramics.

The influence of crown-to-implant ratio in single crowns on clinical outcomes: A systematic review and meta-analysis.

STATEMENT OF PROBLEM: A consensus about the effect of crown-to-implant (C/I) ratio in single crowns regarding the implant survival rate and marginal bone loss (MBL) is lacking. PURPOSE: The purpose of this systematic review and meta-analysis was to evaluate the influence of C/I ratio in implant-supported single crowns on clinical outcomes. MATERIAL AND METHODS: The search was made in the PubMed/MEDLINE, Scopus, and the Cochrane Library databases following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses criteria and registered with the International Prospective Register of Systematic Reviews (PROSPERO: CRD42018095711). The focused question was "Does the crown-to-implant ratio influence clinical outcomes for implant-supported single crowns?" RESULTS: Five direct comparative studies were included (C/I ratio ≤1 or >1, or ≤2 or >2), including a total of 262 participants with a mean age of 54.5 years. The meta-analysis comparing C/I ratio between ≤1 or >1 revealed no significant differences (P=.18; risk difference:-0.05; 95% confidence interval: -0.11 to 0.02) in terms of implant survival rate; the same was true for C/I ratio between <2 or ≥2 (P=.05; risk difference:-0.06; 95% confidence interval: -0.12 to -0.00), both analysis were made with a mean follow-up period was 36 months. The mean MBL was calculated based in the qualitative data for each C/I ratio: ≤1 (0.15 mm [-0.34 to 0.34]); >1 (0.07 mm [-0.29 to 0.22]); <2 (1.32 mm [0.38-0.9]); and ≥2 (1.37 mm [-0.02 to 0.91]). The qualitative data reported that the most common mechanical complication was screw loosening, and the most common biological complication was peri-implantitis. CONCLUSIONS: The meta-analysis revealed no relationship between categories of C/I ratio for implant survival rate. The qualitative data also suggested that MBL increased as the C/I ratio increased.

Pterygomaxillary Disjunction and its Influence on the Result of Surgically Assisted Maxillary Expansion: A Systematic Review and Meta-analysis.

AIM: The aim of this study was to evaluate the available evidence to identify the influence of pterygomaxillary disjunction on the result of surgically assisted maxillary expansion. BACKGROUND: LeFort I type osteotomy with disjunction of the pterygomaxillary suture is a procedure widely used in maxillofacial surgery. However, the need for its performance during surgically assisted maxillary expansions has been discussed in literature, since serious complications can be caused during this stage. REVIEW RESULTS: Systematic review of articles was performed using three databases (PubMed, Web of Science, and Cochrane) published until May 2019. After applying the selection criteria, five articles were included in the systematic review, with a total of 141 patients. Meta-analysis showed the absence of significant difference between intervention and control groups in the preoperative period (standardized mean difference = -0.28; confidence interval, CI 95% = -0.81, 0.26; p = 0.31) and postoperative period (standardized mean difference = -0.12; 95% CI = -0.65, 0.42; p = 0.66). In general, the heterogeneity of statistical estimates was low (I2 = 0%). CONCLUSION: No statistically significant difference was observed between control group (without pterygomaxillary disjunction) and intervention group (with pterygomaxillary disjunction). CLINICAL SIGNIFICANCE: Based on the data analyzed in this systematic review, it could be concluded that pterygomaxillary disjunction is not a mandatory step to achieve satisfactory maxillary expansion. Thus, not performing pterygomaxillary disjunction can prevent complications and reduce surgical time.

Does non-surgical periodontal treatment influence on rheumatoid arthritis? A systematic review and meta-analysis.

OBJECTIVE: The objective of this systematic review was to evaluate the efficacy of non-surgical periodontal therapy on rheumatoid arthritis activity. MATERIAL AND METHODS: Articles published until April 2019 were electronically searched and screened using PubMed / MEDLINE, Scopus, and Cochrane databases according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines (PRISMA). This study was recorded in the international PROSPERO database (CRD42019132205). The PICO question (population, intervention, comparison, results) was: in adult patients with rheumatoid arthritis and periodontitis (P), does non-surgical periodontal treatment (I), as compared to no treatment (C), provides better outcomes in rheumatoid arthritis activity (O). RESULTS: After searching the databases, seven articles were selected for qualitative and five for quantitative analysis. The total number of participants included was 292, with an average age of 50.5 years. All patients had rheumatoid arthritis and periodontal disease. Non-surgical periodontal treatment significantly reduced Disease Activity Score 28 (P = 0.004; I2 = 92%) and erythrocyte sedimentation rate (P = 0.01; I2 = 78%), but with no significant effect on C-reactive protein (P = 0.34; I2 = 92%). CONCLUSIONS: It can be concluded that non-surgical periodontal treatment can benefit patients with rheumatoid arthritis.

Evaluation of Marginal Misfit of Implant-Supported Fixed Prostheses Made Using Different Techniques.

PURPOSE: To evaluate the vertical marginal (VM) and horizontal marginal (HM) misfit of frameworks made using different techniques. MATERIALS AND METHODS: A total of 30 frameworks were divided into three groups of 10 samples each based on manufacturing technique: nichrome cast (G1), milled in zirconia (G2), and milled in wax and fused to metal (G3). Marginal misfit was measured using a three-dimensional optical microscope. RESULTS: The highest VM misfit was in G3 (83.5 µm), followed by G1 (55 µm) and G2 (42 µm). The highest HM misfit was in G2 (118 µm), followed by G3 (102 µm) and G1 (-85 µm). CONCLUSION: Frameworks milled in zirconia resulted in the lowest VM misfit, while frameworks filled in wax and fused to metal resulted in higher VM. The HM misfit was favorable in the lost-wax technique.

Biomechanical Three-Dimensional Finite Element Analysis of Single Implant-Supported Prostheses in the Anterior Maxilla, with Different Surgical Techniques and Implant Types.

PURPOSE: The aim of this study was to use three-dimensional finite element analysis to analyze the stress distribution transferred by single implant-supported prostheses placed in the anterior maxilla using different connections (external hexagon, internal hexagon, or Morse taper), inclinations of the load (0, 30, or 60 degrees), and surgical techniques for placement (monocortical/conventional, bicortical, or bicortical with nasal floor elevation). MATERIALS AND METHODS: Nine models representing a bone block of this region were simulated by computer-aided design software (InVesalius, Rhinoceros, SolidWorks). Each model received one implant, which supported a cemented metalloceramic crown. Using FEMAP software, finite elements were discretized while simulating a 178-N load at 0, 30, and 60 degrees relative to the long axis of the implant. The problem was solved in NEi Nastran software, and postprocessing was performed in FEMAP. Von Mises stress and maximum principal stress maps were made. RESULTS: The von Mises stress analysis revealed that stress increased with increasing inclination of the load, from 0 to 30 to 60 degrees. Morse taper implants showed less stress concentration around the cervical and apical areas of the implant. The bicortical technique, associated or not with nasal floor elevation, contributed to decreasing the stress concentration in the apical area of the implant. Maximum principal stress analysis showed that the increase in inclination was proportional to the increase in stress on the bone tissue in the cervical area. Lower stress concentrations in the cortical bone were obtained with Morse taper implants and the bicortical technique compared with other connections and surgical techniques, respectively. CONCLUSION: Increasing the inclination of the applied force relative to the long axis of the implant tended to overload the peri-implant bone tissue and the internal structure of the implants. The Morse taper connection and bicortical techniques seemed to be more favorable than other connections or techniques, respectively, for restoring the anterior maxilla.