This study aimed to evaluate the influence of denture cleansers on the color, stability, and surface roughness of three-dimensional (3D)-printed denture base resins modified with zirconium dioxide nanoparticles (nano-ZrO₂). A total of 440 specimens were fabricated using one heat-polymerized resin, and two 3D-printed resins (NextDent and ASIGA). According to the nano-ZrO₂ content, the specimens for each resin were divided into five groups (0%, 0.5%wt, 1%wt, 3%wt, and 5%wt). Each concentration was divided into four subgroups (n = 10) based on the immersion solution (distilled water, sodium hypochlorite, Corega, and Fittydent) and immersion duration (360 and 720 days). The color changes (∆E₀₀) and surface roughness (Ra, µm) of each specimen were measured at different time intervals (base line, 360 days, 720 days) using a spectrophotometer and a non-contact profilometer, respectively. The results were statistically analyzed using ANOVA and a post hoc Tukey’s test (α = 0.05). Sodium hypochlorite showed the highest significant color change of all the denture base resins (p < 0.001). The average value of ΔE₀₀ for sodium hypochlorite was significantly higher than the values for the other solutions (Fittydent, Corega, and water) (p < 0.001). Color stability was significantly affected by immersion time for all types of solutions except Corega (p < 0.001). All of the tested immersion solutions (distilled water, sodium hypochlorite, Corega, and Fittydent) showed a significant increase in the surface roughness of all the denture base resins (p < 0.05). Surface roughness was substantially increased by immersion time for all types of solution except Fittydent (p < 0.001). Denture cleansers can result in substantial color change and affect the surface roughness of unmodified and nanoparticle-modified denture base resins. Therefore, the selection of denture cleanser and appropriate types of material is critical for denture longevity.

Background: With the growing demand for sustainable dental practices, chitosan has evolved as an eco-friendly disinfectant for polyether impressions. Objectives: The present study investigated the disinfectant efficacy of chitosan on the dimensional accuracy of polyether (PE) impression material. Methods: A total of 63 polyether impressions (Impregum^TM, Penta^TM, 3M ESPE, Boca Raton, FL, USA) were prepared from the master 3D-printed model, each consisting of a single unit abutment facing two units’ abutments. Three groups of these subjects were used, while each group comprised 21 impressions, respectively. Group 1 is used as a control group and is not subjected to chemical disinfection. Group 2 is spraying group, in which the PE impressions were sprayed with 0.5% chitosan with a high molecular weight. Group 3 is the immersion group, in which the impression was immersed for 15 min in 0.5% chitosan with a high molecular weight. The data collected were analyzed using SPSS 28.0 and the difference in dimensional accuracy between the groups was measured using a one-way ANOVA. Results: Both the intra-and inter-abutment measurements (MD and OG) showed no statistically significant differences in the dimensional changes between the control and the study groups, while the cross-arch distance showed a statistically significant difference in the dimensional change between control and immersion group, p = 0.000. Conclusions: While chitosan disinfection induced slight dimensional changes in polyether impressions, these alterations remained within clinically acceptable limits. The spray application method appeared to be preferable to immersion, as it resulted in less pronounced dimensional changes.

Background: Shade selection is a critical procedure of any esthetic prosthodontic treatment process. Despite its importance, there is a concern regarding the awareness and knowledge of shade selection among dental students and practitioners. Purpose: To evaluate the knowledge of dental students and practitioners regarding shade selection principles and investigate the differences in aesthetic prioritization between fixed and removable prostheses. Additionally, to investigate the emphasis placed on aesthetics in removable prosthetic cases compared to fixed prostheses, and to examine how this emphasis differs between dental students and experienced practitioners. Methods: A cross-sectional questionnaire-based study was conducted involving students and dental practitioners. The questionnaire consisted of multiple-choice questions designed to evaluate participants’ knowledge of shade selection principles and methods used in contemporary dental clinical practice and the perceived impact on treatment outcomes in Saudi Arabia. This study involved 554 participants, divided into three groups: 117 who treated fixed cases, 51 who treated removable cases, and 398 who treated both fixed and removable cases. The collected data was tabulated for data analysis using the Mann–Whitney U test and the Kruskal–Wallis test to generate the significance per category. Results: The study revealed no significant differences in knowledge and practice scores across the demographic factors for participants who exclusively treated either fixed or removable cases, suggesting a uniformity in expertise and application. However, among participants who managed both fixed and removable cases, significant variations emerged based on gender, age, and educational or professional level. Notably, a statistically significant disparity (p < 0.05) was observed in the comprehension of digital shade-matching technology, with practicing dentists exhibiting a higher level of awareness compared to dental students. Conclusions: The study concluded that age, gender, and education level significantly impact the knowledge and practice of shade selection. The findings highlighted a concerning gap in the awareness and knowledge regarding shade selection by dental students compared to practitioners, which emphasizes the need for enhanced educational training programs focusing on shade selection techniques and their implications for prosthodontic outcomes.