Novel dentin bonding pretreatment using copper sulfate (CuSO₄) and dipotassium hydrogen phosphate (K₂HPO₄) may create a more hydrophobic environment for dentin bonding. Thus, this study aims to investigate the impact of a CuSO₄ + K₂HPO₄ pretreatment on dentin μTBS when bonded with a universal adhesive to conventional and CAD/CAM resin composites. Eighty recently extracted human molars (n = 80) were chosen and placed in transparent acrylic blocks to expose the crowns entirely. Nano-filled resin composite and CAD/CAM resin blocks were selected. Based on the dentin pretreatment, type of resin composite, and adhesion strategy, the teeth were randomly allocated into eight equal groups (n = 10). The microtensile bond strength (μTBS) and fracture mode were determined. A three-way analysis of variance (ANOVA) was used to analyze the μTBS data, followed by Tukey’s post hoc test. The μTBS values were not significantly affected by either the resin composite type (p > 0.05) or the adhesive strategy (p > 0.05) according to the three-way ANOVA results. Conversely, significant differences were detected between no dentin pretreatment (24.20 ± 4.54 MPa) and CuSO₄ + K₂HPO₄ pretreatment (33.66 ± 5.22 MPa) using an etch-and-rinse adhesive strategy for nano-filled composites (p < 0.001). Additionally, significant differences were detected between no dentin pretreatment (24.71 ± 4.33 MPa) and CuSO₄ + K₂HPO₄ pretreatment (32.49 ± 4.92 MPa) using an etch-and-rinse adhesive strategy for CAD/CAM resin blocks (p < 0.001). Moreover, significant differences were detected between no dentin pretreatment (21.20 ± 3.40 MPa) and CuSO₄ + K₂HPO₄ pretreatment (30.31 ± 3.87 MPa) using a self-etching adhesive strategy for nano-filled composites (p < 0.001). Also, significant differences were detected between no dentin pretreatment (23.89 ± 3.89 MPa) and CuSO₄ + K₂HPO₄ pretreatment (31.22 ± 4.71 MPa) using a self-etching adhesive strategy for CAD/CAM resin blocks (p < 0.001). In conclusion, dentin μTBS was enhanced by a copper-based treatment when used with nano-filled and CAD/CAM resin blocks.

Objective: The current investigation aims to assess the clinical efficacy of intraoral photographic assessment in detecting dental caries of varying severity and to assess different variables, such as the type of dentition, examiner experience, and the type of imaging equipment, on evaluative clarity. Methods: This meta-analysis of the PRISMA-DTA systematic review and diagnostic test accuracy was conducted. They searched electronic databases such as PubMed, Web of Science, Scopus, Embase, and Cochrane Library from the beginning of time up to January 2025. The studies had to have evaluated intraoral photographic caries because they were required to have compared it with clinical intraoral examination and provide extractable tooth-level 2 × 2 data. Enamel (ICDAS 1 3), dentine (ICDAS 4 6), and any caries (ICDAS 1 6) were analyzed separately in a meta-analysis. A random-effects model was used to compute pooled sensitivity, specificity, diagnostic odds ratio (DOR), and summary receiver operating characteristic (SROC) curves. Subgroup analysis was done on a pre-specified basis according to dentition, type of examiner, and imaging device. This study has been registered in PROSPERO with reference number 2026 CRD420261330820. Results: Twenty-three studies were retrieved through a comprehensive search and were stratified by severity into three categories. In the case of enamel caries, sensitivity was 0.65 (95% CI: 0.62–0.68), specificity was 0.95 (95% CI: 0.94–0.95), DOR was 36.74 (95% CI: 12.44–108.49), and the AUC was 0.87. In the case of dentine caries, the pooled sensitivity and specificity were 0.86 (95% CI: 0.85–0.87) and 0.96 (95% CI: 0.96–0.97), respectively, which produced the DOR of 176 (95% CI: 91.2–339.6) and the AUC of 0.94. Any caries had a pooled sensitivity of 0.81 (95% CI: 0.80–0.83), specificity of 0.97 (95% CI: 0.96–0.97), DOR of 64.04 (95% CI: 11.65–351.94), and AUC of 0.888. Subgroup analyses revealed that diagnostic accuracy was greater when the lesions were severe. Conclusions: Intraoral photographic assessment has a moderate level of accuracy in detecting enamel lesions and has a clinically acceptable level of accuracy in detecting dentine caries. The clinical efficacy increased with the severity of lesions and was consistent with high specificity at all levels of threshold. Imaging on smartphones could be a promising method for caries screening.

In-office bleaching with hydrogen peroxide (HP) is effective, but prolonged application times and multiple sessions may alter the enamel surface and trigger adverse cellular responses. TiO₂-assisted HP bleaching could enhance whitening efficacy while reducing the application time. This study evaluated whether TiO₂ incorporation could improve bleaching efficiency with a shorter application time while limiting adverse enamel and cellular effects. Forty enamel–dentin specimens were assigned to four bleaching protocols (n = 10): 40% HP for 40 min (G1), 40% HP containing 1 wt% TiO₂ for 20 min (G2) or 40 min (G3), and 40% HP for 20 min (G4). All groups received standardized LED irradiation. Evaluations included color change, enamel microhardness, and surface roughness. Conditioned media were applied to human dental pulp stem cells (hDPSCs) and evaluated the cellular oxidative response in hDPSC lysates using a commercial Human ROS ELISA assay. Cellular metabolic activity and morphology were assessed by MTT assay, phase-contrast microscopy, and scanning electron microscopy (SEM), respectively. All protocols resulted in measurable whitening, and G2 showed whitening performance comparable to G1 despite half the application time. G1 showed the lowest post-treatment microhardness and the highest surface roughness, whereas G4 showed the least alteration to enamel. ROS ELISA measurements differed among the experimental conditions, with the highest level observed in G3. All conditioned media reduced hDPSC metabolic activity related to the control, with differences among the bleaching protocols and exposure periods. According to the results of this in-vitro study, incorporating 1 wt% TiO₂ into HP bleaching gel under LED irradiation enabled a shorter application protocol to achieve whitening comparable to the conventional longer-duration protocol while reducing enamel surface alterations. Although TiO₂-assisted protocols produced higher cellular ROS levels, these levels did not show a directly proportional relationship with cellular metabolic activity or morphology.