This systematic review and network meta-analysis aimed to compare different PMMA (polymethyl methacrylate) complete denture base manufacturing techniques by evaluating their mechanical properties. The objective was to determine which method-compression molding, injection molding, milling, or 3D printing-offers the best performance. In vitro studies investigating mechanical properties of PMMA denture base resins. Four electronic databases such as PubMed, Embase, Web of Science, and the Cochrane Library were screened for English language articles. Two independent researchers selected studies, extracted data, assessed risk of bias, and evaluated evidence certainty. A total of 17152 articles were found by electronic databases. Finally, 63 studies were analyzed, using random-effects model for network meta-analysis. The outcomes investigated were flexural strength, flexural modulus, surface roughness, impact strength, and Vickers hardness. Milling consistently ranked first or second across outcomes, excelling in flexural strength, modulus, and surface roughness. In contrast, 3D-printed denture bases demonstrated the lowest mechanical performance, highlighting the limitations of this technique at present. Milling is generally recommended for PMMA denture bases due to its superior mechanical properties across most outcomes, supporting its use in clinical settings. However, while promising, 3D-printed PMMA denture bases require further improvement to meet clinical performance standards.

With increasing esthetic needs, patients prefer missing anterior teeth to be restored as soon as possible, but how the timing of implantation and prosthetic loading influences peri-implant tissue and the esthetic results remains unclear. The purpose of this systematic review and network meta-analysis of randomized controlled trials was to investigate and rank the hard-tissue and soft-tissue outcomes, esthetics, and patient satisfaction of single maxillary implant placement and loading protocols. A systematic search was conducted to identify studies with at least a 1-year follow-up that compared different implant placement and loading protocols and reported on survival, marginal bone loss (MBL), soft tissue, and esthetics. A random effects model and a Bayesian approach were applied to compare protocols by using mean differences (MD) with 95% credible intervals (CrI) and surface under the cumulative ranking curve (SUCRA) values. A total of 43 articles were included, with a follow-up of 1 to 5 years. All protocols had high survival rates and no significant differences for 1-year or 2-year MBL. Immediate placement with immediate loading ranked first in pink and white esthetic scores and satisfaction and was statistically significantly better than immediate placement with delayed loading or late placement protocols in pink esthetic scores, where its advantage over late placement with late loading was also clinically relevant [MD: -1.74, CrI: -2.34 to -1.15]. Immediate implantation with immediate loading showed a considerable esthetic advantage over later rehabilitation, whereas only a slight difference in MBL resulted from different protocols.

We conducted a meta-analysis and systematic review to investigate the efficacy of chitosan-containing chewing gums, and to test their inhibitory effects on Streptococcus mutans. The systematic search was performed in three databases (Cochrane Library, EMBASE, and PubMed) and included English-language randomized–controlled trials to compare the efficacy of chitosan in reducing the number of S. mutans. To assess the certainty of evidence, the GRADE tool was used. Mean differences were calculated with a 95% confidence interval for one outcome: bacterial counts in CFU/mL. The protocol of the study was registered on PROSPERO, registration number CRD42022365006. Articles were downloaded (n = 6758) from EMBASE (n = 2255), PubMed (n = 1516), and Cochrane (n = 2987). After the selection process, a total of four articles were included in the qualitative synthesis and three in the quantitative synthesis. Our results show that chitosan reduced the number of bacteria. The difference in mean quantity was −4.68 × 10⁵. The interval of the random-effects model was [−2.15 × 10⁶; 1.21 × 10⁶] and the prediction interval was [1.03 × 10⁷; 9.40 × 10⁶]. The I2 value was 98% (p = 0.35), which indicates a high degree of heterogeneity. Chitosan has some antibacterial effects when used as a component of chewing gum, but further studies are needed. It can be a promising antimicrobial agent for prevention.

Objectives: Digital impression-taking techniques are widely used due to their many advantages. However, the accuracy of intraoral scanning in full-arch cases remains a matter of debate. The reliability of different digital implant impression techniques remains questionable in completely edentulous, full-arch cases. This review investigated the accuracy of digital implant impression techniques for full-arch use. Methods: Our study protocol was registered in the PROSPERO database (CRD42023393091). Data reporting was based on the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) 2020 guidelines, by the Cochrane Handbook. Comparative in vitro studies matching the PICO framework were included. A systematic search was conducted in four databases: PubMed (MEDLINE), EMBASE, Web of Science and the Cochrane Library (Cochrane Central Register of Controlled Trials [CENTRAL]). Results: Thirty-four papers were included in analyzing trueness and precision of root mean square (RMS) deviations. No significant differences were observed between test groups. The overall RMS trueness deviation was 53.36 μm [18.44; 88.28] in the extraoral stereophotogrammetry group, 73.88 μm [36.68; 111.09] in the conventional impression group, 99.54 μm [56.22; 142.86] in the IOS plain group, 104.88 μm [36.86; 172.90] in the IOS scanaid group, and 65.58 μm [5.24; 125.92] in the IOS splinted group. Substantial heterogeneity was observed across studies (I² ≈ 100%) Conclusions: In case of completely edentulous jaws restored with four to eight implants, digital techniques showed comparable accuracy to the conventional method with no statistically significant differences detected.

Background/Objectives: Alternative nicotine-containing products have gained popularity in recent years. Our aim is to compare clinical periodontal outcomes following non-surgical periodontal therapy (NSPT) among patients with periodontitis according to nicotine exposure status: cigarette smokers (CS), former smokers (FS), quitters (Q), users of electronic cigarettes (EC), smokeless tobacco users (ST), and non-smokers (NS). Methods: A systematic search of four electronic databases (PubMed, EMBASE, Web of Science, CENTRAL) was performed until January 2025. Sixty-seven studies were included in the qualitative synthesis, of which 56 studies were included in a frequentist network meta-analysis. Two researchers independently collected data on probing pocket depth (PPD), clinical attachment loss, bleeding on probing, plaque index, full mouth plaque score, gingival index, and gingival crevicular fluid volume. Results: NS had significantly higher change in PPD compared with CS (MD: 0.25; CI: 0.13, 0.37; 50 studies; 1359 patients; moderate certainty), EC (MD: 0.98; CI: 0.47, 1.49; 2 studies; 56 patients; very low certainty), and ST (MD: 0.99; CI: 0.49, 1.49; 2 studies; 82 patients; low certainty). Q (MD: 0.02; CI: −0.56, 0.60; 2 studies; 52 patients; low certainty) and FS (MD: 0.03; CI: –0.62, 0.69; 4 studies; 267 patients; low certainty) did not differ significantly from NS. In secondary outcomes, NS, FS, or Q were ranked first. Conclusions: FS and Q showed no statistically significant differences from NS; EC and ST generally had less favorable treatment rankings than CS. The certainty of evidence varied across exposure groups and outcomes. Further studies are needed to support firm clinical recommendations.

Background and Objectives: This study compared the antimicrobial effects of chitosan and sodium hypochlorite against Enterococcus faecalis (E. faecalis) at different irrigation solution concentrations. E. faecalis is a persistent pathogen frequently surviving root canal treatment, while sodium hypochlorite remains the current gold-standard irrigation material. Materials and Methods: A systematic review and meta-analysis of in vitro studies was conducted using Cochrane Library, EMBASE, and PubMed. Evidence certainty was assessed with GRADE. Two outcomes were analyzed: colony-forming units (CFU/mL) and the inhibition rate (IR). Two reviewers independently screened studies and extracted data. Results: Of 889 identified records, 10 studies met the inclusion criteria. For CFU/mL, the overall effect was −0.28 (95% CI: −1.54 to 0.97). For IR, chitosan concentrations < 1% showed an effect of –7.35 (95% CI: −27.27 to 12.56), while concentrations ≥ 1% showed an effect of −0.90 (95% CI: −19.24 to 17.45). Conclusions: Chitosan demonstrated antimicrobial activity comparable to sodium hypochlorite in vitro, with concentrations above 1% showing enhanced antibacterial effects. However, methodological heterogeneity limits direct comparison, and clinical equivalence cannot be concluded.