Background/Objectives: The increasing clinical integration of 3D-printed definitive resins requires a comprehensive understanding of their physicochemical properties and adhesive behavior. However, there is limited evidence regarding the optimal surface treatment and bonding strategies for clear aligner composite attachments on these materials. This study aimed to characterize a 3D-printed definitive resin, evaluate the effects of surface treatments on its surface topography, and compare the shear bond strength (SBS) of the bonded attachments using different adhesive systems, both before and after thermocycling. Methods: A total of 120 rectangular specimens were fabricated from a 3D printed dental resin (Crowntec^®, SAREMCO Dental AG—Mexico City, Mexico). For physicochemical characterization, six samples underwent scanning electron microscopy/energy-dispersive spectroscopy, X-ray diffraction, and thermogravimetric analysis. To evaluate surface topography, 42 polished specimens were assigned to three groups: untreated (control), etched with 4% hydrofluoric acid (HFA), or sandblasted with 50 µm Al₂O₃ (AA). Each group was subdivided for SEM observation and surface roughness (Ra) measurement. For SBS testing, 72 additional samples received the same surface treatments and were further subdivided according to the adhesive system: Transbond™ XT Primer (TXT) or Single Bond Universal (SBU). Results: The AA group showed the highest Ra (2.21 ± 0.30 µm), followed by HFA (0.81 ± 0.20 µm) and control (0.07 ± 0.30 µm) (p < 0.001). The highest SBS was observed in the AA + SBU group, followed by AA + TXT. Conclusions: Sandblasting with Al₂O₃ particles, combined with a universal adhesive, significantly improved bond strength, suggesting a viable protocol for 3D printed definitive composites in aligner attachment applications.

Background/Objectives: Edentulism is a prevalent chronic condition among older adults, and conventional complete dentures remain the standard of care. However, their fabrication often involves multiple clinical sessions and operator-dependent steps that may compromise fit and comfort. Digital workflows using CAD/CAM technologies have emerged as viable alternatives, offering improved efficiency, precision, and patient-centered outcomes. This case report aims to present a fully digital workflow for maxillary complete dentures and describe clinical efficiency and patient-reported outcomes. Case Presentation: A 73-year-old edentulous male patient underwent maxillary rehabilitation using a fully digital workflow. The protocol included intraoral scanning; the design and 3D printing of a custom tray with occlusal rims; border-molded functional impressions; virtual articulation; and CAD/CAM fabrication. A digitally designed Try-In denture was 3D printed for clinical evaluation, followed by adjustments. The definitive prosthesis was milled from high-performance PMMA discs using a five-axis milling machine. The workflow reduced the number of appointments and laboratory steps. At six-month follow-up, the patient reported high satisfaction with esthetics, retention, phonetics, and masticatory performance. No significant post-delivery adjustments were required. Conclusions: This case demonstrates that fully digital workflows for maxillary complete dentures are clinically viable, providing excellent precision, patient satisfaction, and time efficiency compared to conventional methods. The reproducible protocol described may support the broader integration of CAD/CAM technologies in edentulous rehabilitation.

Background/Objectives: Residual EDTA may persist after smear-layer removal and after the application of contact sealers during setting. This in vitro study compared the effect of 1 min of pre-setting surface contact with 17% EDTA (vs. distilled water) on a calcium silicate-based sealer (AH Plus Bioceramic Sealer) and an epoxy resin-based sealer (AH Plus). Methods: Discs were prepared (N = 108) in a 2 × 2 design (n = 27/group); per group; n = 12 were used for solubility followed by eluate pH using the same specimens/eluates after 24 h immersion in distilled water; n = 12 were used to test Vickers microhardness on an independent set after setting; and n = 3 were used for SEM/EDS. Results: Data were analyzed at α = 0.05 using Kruskal–Wallis tests followed by Bonferroni-adjusted pairwise Mann–Whitney U tests for solubility and eluate pH, and one-way ANOVA was performed followed by Tukey’s post hoc test to assess the microhardness. Solubility differed among groups (p < 0.001) and was higher for the bioceramic sealer than for the resin sealer; pre-setting EDTA exposure increased solubility for the AH Plus Bioceramic Sealer (0.86 ± 0.08% to 1.30 ± 0.16%) and decreased solubility for AH Plus (0.34 ± 0.04% to 0.22 ± 0.03%) (p < 0.05). The eluate pH also differed among groups (p = 0.001) and was higher for the bioceramic sealer (≈11.7) than for the resin sealer (≈8.7–9.3), with no within-material differences (p = 0.999 and p = 0.851). Microhardness differed among groups (p < 0.001) and was higher for AH Plus (239.70–246.92 HV) than for AH Plus Bioceramic (131.72–170.83 HV); EDTA reduced microhardness only for the bioceramic sealer (p < 0.001), with no significant change for AH Plus (p = 0.475). Descriptive SEM/EDS findings suggested increased surface irregularities and lower surface Ca for AH Plus Bioceramic after EDTA exposure (12.68 to 7.31 wt%). Conclusions: Pre-setting EDTA contact therefore produced material-dependent changes in early properties and adverse surface-related effects in the calcium silicate-based sealer, supporting thorough chelator removal before obturation.

Background: Metallic and metal oxide nanoparticles are increasingly explored as antimicrobial biomaterials in endodontics due to their multi-target mechanisms of action, largely mediated by metal ion release (e.g., Ag⁺, Cu⁺). However, bacterial metal resistance systems, particularly efflux-related proteins, may influence their antimicrobial performance. This study aimed to analyze the prevalence and distribution of metal resistance-associated proteins in bacteria involved in endodontic infections using a bioinformatic approach. Methods: An in silico, cross-sectional bioinformatic analysis was conducted using publicly available genomes from the Bacterial and Viral Bioinformatics Resource Center (BV-BRC). Bacterial species associated with acute apical abscess (AAA), symptomatic apical periodontitis (SAP), asymptomatic apical periodontitis (AAP), and post-treatment apical periodontitis (PTAP) were included. The presence of selected metal resistance-related proteins (CutC, CopA, CzcA, CusA, SilA, P-type ATPase, and PA3920) was assessed using a binary presence/absence framework. Prevalence, group comparisons (Fisher’s exact test), and co-occurrence patterns (Phi coefficient) were analyzed. Results: Metal resistance-associated proteins were widely distributed across all infection types, with prevalence ranging from 70.0% to 82.9% and no significant differences between groups (p > 0.05). CutC was the most prevalent protein, followed by CopA and CzcA, whereas SilA and PA3920 were not detected. Correlation analysis revealed consistent co-occurrence patterns among key taxa, including Porphyromonas gingivalis, Fusobacterium nucleatum, and Prevotella spp. Conclusions: Metal resistance-related proteins are broadly distributed in endodontic microbiota, indicating a conserved genetic capacity for metal tolerance. These findings suggest that microbial resistance determinants may influence, but do not directly determine, the antimicrobial performance of nanoparticle-based biomaterials. This study provides a hypothesis-generating, bioinformatic framework to support the design and optimization of antimicrobial biomaterials, highlighting the need for experimental validation and integration of phenotypic and biofilm-based analyses.