Introduction: Bruxism, defined as repetitive masticatory activity, is a common condition with a multifactorial etiology. Although linked to stress and personality traits, few studies have examined medical students – a population with chronic academic stress, whose specialized knowledge may enhance self-report reliability. This study aimed to assess the association between personality traits and self-reported bruxism in this group. Material and methods: A cross-sectional survey was conducted among 204 students of the Medical University of Silesia (150 women, 54 men). Bruxism was assessed by self-report using a modified version of the Baron et al. questionnaire, while personality traits were measured with the NEO-FFI inventory. Group differences (non-bruxism, awake bruxism – AB, sleep bruxism – SB) were analyzed using ANOVA, and predictors of bruxism status evaluated through logistic regression. Results: Based on self-report, 56 participants (27.5%) were classified as having bruxism, including 26 (12.8%) with SB. ANOVA indicated significant differences only for conscientiousness (F(2,201) = 4.57; p = 0.011), with lower scores in the SB group compared to non-bruxers (p = 0.0088). Logistic regression showed higher conscientiousness was associated with lower odds of being classified as a bruxer; however, this association was borderline (OR = 0.87; 95% CI: 0.76–1.00; p = 0.051). No significant associations were observed for neuroticism, extraversion, openness, or agreeableness. Conclusions: In this cohort, lower conscientiousness was the most consistently observed trait associated with self-reported bruxism, particularly its sleep subtype. The multivariable findings were borderline and overall predictive performance modest; therefore, the results should be considered exploratory and hypothesis-generating, pending confirmation in studies using objective bruxism assessment.

Background: Reliable mesiodistal tooth-width measurements are essential for orthodontic diagnosis and treatment planning. Digital models obtained by scanning plaster casts may facilitate orthodontic workflows; however, the extent of agreement between manual caliper measurements and digital measurements on digitized plaster models remains clinically relevant, particularly at the individual-tooth level. Objective: To evaluate the agreement, repeatability, and inter-method differences between manual and digital mesiodistal tooth-width measurements from the canine to the first molar on digitized plaster models. Methods: Plaster models from 30 orthodontic patients were analyzed. The models were digitized using a 3Shape TRIOS 4 intraoral scanner. Mesiodistal widths of teeth 13–16, 23–26, 33–36, and 43–46 were measured using digital calipers on plaster models and using 3Shape Unite platform version 1.7.33.2 (3Shape A/S, Copenhagen, Denmark) on the corresponding digital models. Manual and digital measurements were each performed twice at 24 h intervals. For both methods, the mean of the two repeated measurements was used for inter-method comparison. Manual and digital intra-observer repeatability was assessed using the intraclass correlation coefficient (ICC). Inter-method differences (ΔMD = mean manual − digital) were analyzed using Bland–Altman analysis. Differences exceeding 0.3 mm were considered to exceed the predefined threshold of potential clinical relevance. Results: A total of 480 teeth were analyzed. Manual and digital intra-observer repeatability were excellent (ICC = 0.985 and ICC = 0.976, respectively). Manual measurements were on average 0.150 mm higher than digital measurements (SD = 0.407 mm; median = 0.145 mm; IQR = 0.29 mm), with 95% limits of agreement ranging from −0.647 mm to 0.947 mm. At the single-tooth level, 212 out of 480 measurements (44.2%) exceeded the predefined 0.3 mm threshold. First molars and selected premolars showed the highest discrepancy rates, whereas canines generally showed lower discrepancy rates. Conclusions: Manual and digital mesiodistal tooth-width measurements performed on digitized plaster models showed good agreement under the tested conditions. However, individual tooth-level differences exceeding the predefined 0.3 mm threshold were frequent, particularly for posterior teeth. Therefore, digital measurements obtained from digitized plaster models should be interpreted with caution in clinical situations requiring high precision at the level of individual tooth dimensions.