Bone mineral density (BMD) is related to oral health. This study investigated how changes in BMD influence tooth loss risk and dental caries prevalence. This cross-sectional observational study included 224 people (199 males and 25 females). The BMD scores of the participants’ lumbar spine, femoral neck, and total hip were categorized as normal, osteopenia, or osteoporosis. Oral health was assessed using the Decayed, Missing, Filled Teeth (DMFT) index and Oral Hygiene Index-Simplified (OHI-S) scores. Based on the number of surviving teeth, the participants were categorized into low (< 20) and high (≥ 20) groups. Differences between groups were assessed using independent sample T tests and one-way analysis of variance. The normal, osteopenia, and osteoporosis groups comprised 72, 87, and 65 participants, respectively. The OHI-S scores showed no notable variations across the groups. The DMFT index scores were highest (18.69) in the osteoporosis group and lowest (14.08) in the normal group (p < 0.001). Although the number of remaining teeth was lower in the osteoporosis and osteopenia groups compared to the normal group (p < 0.001), that in the osteopenia group approximated the normal group, but was substantially higher than in the osteoporosis group. The group with the lowest number of remaining teeth had lower total hip T-scores, despite significantly higher DMFT indexes (p < 0.001). Tooth loss and dental decay rates were significantly high in patients with osteoporosis. Although bone resorption during osteopenia is not excessive, it constitutes a crucial risk factor for dental health. Therefore, attention must be paid to bone resorption treatment in patients with osteopenia.

Objective: This finite element analysis study aims to evaluate the effects of restoring 1 mm and 2 mm diastemas in maxillary anterior incisors with different CAD-CAM materials on stress distribution and to compare full crown and laminate veneer restorations. Materials and methods: Maxillary anterior tooth models simulating laminate veneer and full crown restorations were created. The experimental groups were categorized into four based on diastema width (1 mm and 2 mm) and CAD-CAM materials. Loads of 50 N, 150 N, and 250 N were applied vertically at 0° and obliquely at 30° and 60° angles to the central incisor’s incisal midpoint. Von Mises stress values were analyzed numerically and visually with color-coded comparisons for all models. Results: When laminate veneer restorations were used to close diastemas, the highest stress values under a 250 N vertical load and 2 mm diastema were observed in the lateral incisor. IPS E.max exhibited a stress value of 166.88 MPa for the superstructure, while Lava Ultimate recorded 35.49 MPa in the lateral incisor. Within the dentin, the highest stress was 45.92 MPa for IPS E.max and 65.74 MPa for Lava Ultimate in the lateral incisor. When full crown restorations were employed, the highest stress values under a 250 N vertical load were again recorded in the lateral incisor. IPS E.max showed a stress value of 198.03 MPa for the superstructure, while Lava Ultimate demonstrated 40.80 MPa. The highest stress values within the dentin were 65.20 MPa for IPS E.max and 65.74 MPa for Lava Ultimate in the lateral incisor. Conclusions: This finite element analysis highlights that the type of restoration and diastema width significantly affect stress distribution in anterior teeth. IPS E.max material exhibited higher stress values, leading to more significant stress accumulation than other materials in laminate veneer and full crown restorations. Additionally, Lava Ultimate showed the highest stress values within the dentin. These findings underscore the importance of selecting appropriate CAD-CAM materials and restoration types to optimize stress distribution in diastema closures, providing critical insights for restoration planning.

Aim: This study evaluated dental students perception of smile aesthetics regarding midline devia-tion and diastema, and examined differences by gender, prior treatment, and education level. Material and Methods: A total of 550 students were invited, 415 responded, and 400 valid questionnaires (268 females, 132 males) were included in the final analysis. Nine digitally modi-fied images were produced from one facial photograph to show midline deviations (0 mm, 1 mm, 2 mm) and diastema widths (0 mm, 1 mm, 2 mm). Students rated each image on a Visual Analog Scale (0–10). Because the same participants rated all nine images, differences among the nine smile conditions were analyzed using the Friedman test. When significant, post-hoc pairwise comparisons were performed using the Wilcoxon signed-rank test with Bonferroni correction (adjusted α = 0.001389). Between-group comparisons (gender, education level, treatment histo-ry) were analyzed using the Mann–Whitney U test. Results: The Friedman test revealed statistically significant differences among the nine smile conditions (χ² (8) = 2536.21, p < 0.001; Kendall’s W = 0.79), indicating a large effect size. Post-hoc Wilcoxon signed-rank tests with Bonferroni correction (adjusted α = 0.001389) demonstrat-ed that all pairwise comparisons were statistically significant. The control condition received the highest aesthetic ratings (median 8 (7–9)), whereas the lowest ratings were observed for the 2 mm deviation + 2 mm diastema condition (median 2 (1–3)). Conclusion: Even minor midline deviation or diastema reduced perceived smile aesthetics, and combined discrepancies produced the greatest reduction, with the 2 mm deviation + 2 mm dia-stema condition rated the least aesthetic.