Purpose: Maxillary anterior tooth dimensions are critical in esthetic and restorative dentistry, yet data remain limited for some populations. Existing reference values may not apply universally, and sex-related differences are underreported. This study examined the clinical crown width (w), length (l), and width/length ratio (w/l) of maxillary central incisors, lateral incisors, and canines in a Kuwaiti adult population, and evaluated the sex-related differences. Patients and Methods: Maxillary 3D resin models were obtained from 126 healthy adults. Mesiodistal width (w) and clinical crown length (l) were measured with a digital caliper (0.01 mm). The w/l ratio was calculated, and reproducibility was tested on 24 models. Sex differences were assessed with independent sample t-tests. Results: Of the participants, 84 (66.6%) were female and 42 (33.4%) were male, with a mean age of 29.8 years. Mean (± SD, range) crown widths were 8.83 ± 0.65 (7.5– 9.8) mm, 6.83 ± 0.52 (6.0– 7.8) mm, and 7.76 ± 0.58 (6.8– 8.7) mm for central, lateral, and canine teeth, respectively. Corresponding lengths were 9.83 ± 0.72 (8.2– 11.2) mm, 8.00 ± 0.60 (7.0– 9.2) mm, and 9.14 ± 0.68 (8.0– 10.4) mm. The corresponding w/l ratios were 91% (centrals), 86% (laterals), and 86% (canines). Statistically significant sex differences were observed in crown length (p < 0.001) and w/l ratio (p < 0.001) for all three tooth types, with males exhibiting longer crowns and females showing higher w/l ratios. Conclusion: Width/length ratios were higher in females across all maxillary anterior teeth, whereas crown length of all anterior teeth and canine width were greater in males, showing the greatest sexual dimorphism. Ethnicity and sex significantly influence maxillary anterior tooth dimensions, highlighting the need for population- and sex-specific reference values to guide esthetic and restorative treatment.

Objective: Selecting suitable materials and luting agents for single crowns is critical yet challenging, as dentists must consider different factors. This study aimed to assess dentists’ preferences for materials and luting agents under different clinical conditions and evaluate the nonclinical factors influencing their preferences. Methods: A paper-based survey supplemented with photographs illustrating anterior and posterior single-crown preparation designs was used, incorporating three clinical scenarios for each as examples. Participants provided demographic data and were asked to select their preferred material and luting agent for each scenario. Comparisons between the crown material/luting agent choices and dentist/practice characteristics were performed. Significant differences were determined using the chi-square test. Results: Overall, 262 (87.3%) dentists participated in this survey. The top-selected material for anterior preparation designs was lithium disilicate; monolithic zirconia was the most selected for posterior preparation designs. Dual-cure resin was the most selected luting agent for all anterior and posterior clinical scenarios, except for posterior subgingival preparation design. There was a significant association between the dentist’s age and the selection of material and luting agent (p < 0.05) in all clinical scenarios, except for the luting agent selection in the posterior subgingival preparation designs (p < 0.05). Other nonclinical factors yielded mixed results; some preparation designs showed significant differences, while others did not, depending on the clinical scenario. Conclusions: Reliance on new materials and luting agents that require minimally invasive treatment with dental ceramics and resin cement is increasing. However, the choice of materials and luting agents is influenced by clinical presentation and nonclinical factors, making it crucial for dentists to be aware of these factors when selecting materials for single-crown restorations. Clinical Implications: An overall trend was observed for the use of strong monolithic ceramics with adhesive resin cements. These findings could assist dentists in reviewing and re-evaluating material choices in their clinical practices, both at a national and regional level. Additionally, the findings could be useful for dental policy makers, wholesale suppliers, and retail distributors in making future decisions.

Objective: This study evaluated how preheating temperature and duration, and light-curing time affect the microhardness (HV) and degree of conversion (DC) of a preheated resin composite used as a luting agent. Materials and methods: A microhybrid composite was preheated to 54 °C or 68 °C for 5, 10, or 15 min, and then placed between a 4.0 mm lithium disilicate overlay and a natural tooth as a luting agent. Light-curing was performed for 120, 180, or 270 s. The microhardness and degree of conversion were measured. Three-way ANOVA analyzed the effects and interactions of the variables. Pearson's correlation assessed the relationship between HV and DC. Results: DC was not significantly affected by preheating temperature, duration, or light-curing time ( p > 0.05). HV was significantly influenced by all variables ( p ≤ 0.001), with the highest HV at 68 °C for 15 min and longer curing. A significant three-way interaction was noted ( p = 0.039). No consistent correlation was found between DC and HV, except for one condition (54 °C, 5 min, 90 s; ρ = 0.97, p = 0.005). Conclusions: Within the preheating conditions evaluated, higher preheating temperatures, longer preheating durations, and extended curing times were associated with increased microhardness, but not the degree of conversion, of the resin composite under ceramic restorations. Clinical significance: Among the preheating protocols evaluated, higher preheating temperatures, longer preheating durations, and extended multidirectional light-curing times were associated with higher microhardness of resin composites used as luting agents beneath thick (4 mm) lithium disilicate restorations, without affecting the degree of conversion. Because no non-preheated control group was included, these findings should be interpreted as comparisons among different preheating protocols rather than evidence of the benefits of preheating itself. Furthermore, the extended curing times investigated in this study represent optimal experimental conditions for the evaluated restoration configuration and may not always be practical or feasible in routine clinical settings. Minimizing the delay between preheating and curing may help preserve the effects associated with the investigated preheating protocols.