## 3 Results
### Studies Included
[63] conducted a study with 100 participants to examine changes in personality traits, attitudes toward orthodontic treatment, and pain perception beforeand after treatment (T1 and T2). At T1, gender differences were evident in neuroticism and agreeableness, but these differences were no longer significant at T2. Post-treatment, neuroticism scores significantly decreased, while openness, agreeableness, and conscientiousness scores increased significantly. Although positive attitudes toward orthodontic treatment were initially reported, improvements were noted post-treatment, particularly among male subjects. Average pain scores remained statistically similar between genders at both timepoints. [PERSON] et al. [52] conducted a cross-sectional study involving 200 adolescents, with equal groups of treated and untreated individuals. The findings revealed a strong positive correlation between pain perception and attitude. Additionally, higher levels of neuroticism were significantly associated with increased pain perception, whereas higher conscientiousness was linked to reduced pain and more favorable attitudes. There was no significant difference in pain perception or attitudes between the treated and untreated groups, but patients with more positive attitudes tended to experience less pain. Gender comparisons revealed no significant differences in pain perception or attitude within either the treated or untreated groups. [PERSON] et al. [54] investigated the association between orthodontic treatment needs, OHRQoL, self-esteem (SE), and personality traits in 189 adults. Total OHIP-14 scores did not differ significantly by gender or across most age groups, although individuals over 50 reported worse OHRQoL. Approximately 79% of subjects were classified as needing orthodontic treatment based on the Dental Health Component (DHC) of the IOTN, compared to 38% based on the Aesthetic Component (AC). Univariate analyses demonstrated modest to weak associations between treatment need and OHRQoL, with higher treatment need correlating with poorer quality of life, particularly in domains such as functional limitations, physical discomfort, psychological discomfort, and psychological disability. Significant links were found between self-esteem and OHRQoL, as well as between personality traits like neuroticism and extraversion and OHRQoL. However, no evidence was found that self-esteem or personality traits moderate the association between OHRQoL and treatment need. [PERSON] et al. [51] examined the effects of personality traits on pain perception and attitudes toward orthodontic treatment in 300 young adults (150 treated and 150 untreated). The study found no significant differences in pain perception or attitudes between treated and untreated groups. A significant correlation was observed between attitude and pain perception, with a more positive attitude linked to less reported pain. Moreover, the analysis of personality traits revealed that higher neuroticism was significantly associated with increased pain perception, while variations in conscientiousness (from very low to very high levels) also significantly influenced pain and were strongly correlated with attitude. [PERSON] et al. [59] conducted a longitudinal study involving 38 children to examine how personality traits influence compliance, measured as the average daily wearing time of removable appliances. The average wearing time was 6.09 h per day (range: 1.38-15.00 h), generally below the prescribed duration. Secondary analyses examined correlations between psychological test outcomes (from both patients and caregivers) and appliance-wearing time. These findings revealed strong positive correlations between wear time and traits such as self-efficacy, conscientiousness, and parental involvement. Although some measurements were rejected based on power analysis, those tests confirmed a significant relationship between psychological factors and patient compliance.