## 3 Results
### Studies Included
\begin{table}
\begin{tabular}{c c c c} \hline \hline
**Study** & **Population Characteristics** & **Instrument Used** & **Main Findings** \\ \hline [PERSON] et al. (2015) [52] & 200 adolescents aged 14–18 years & & Pain perception was similar for treated and untreated groups, indicating no effect of orthodontic treatment on pain perception. \\ [PERSON] et al. (2015) [52] & \begin{tabular}{c} Equal number of males and \\ females (100 each). \\ \end{tabular} & Pain perception and attitude measurement using the VAS scale. & \begin{tabular}{c} Personality traits evaluation \\ with NEO-FFI. \\ \end{tabular} & \begin{tabular}{c} Pain perception was similar for treated \\ and untreated groups, indicating no effect \\ of orthodontic treatment on pain perception. \\ Personality traits, particularly neuroticism \\ and conscientiousness, significantly \\ influenced pain perception and attitude \\ toward orthodontic treatment. \\ Gender and treatment status did not affect \\ pain perception or attitude towards \\ orthodontic treatment. \\ \end{tabular} \\ \hline \hline \begin{tabular}{c} 189 adults aged 17–64 years \\ (mean age 31.3 years). \\ \end{tabular} & Personality traits evaluation with the Dutch adaptation of NEO-FFI. & \begin{tabular}{c} There is a significant association between orthodontic treatment need and oral \\ health-related quality of life (OHRQoL), with higher treatment need correlating \\ with worse OHRQoL. \\ Self-esteem is significantly associated with \\ OHRQoL, where higher self-esteem \\ correlates with other OHRQoL. \\ Certain personality traits are associated \\ with OHRQoL, with OHRQoL, but neither self-esteem nor \\ personality traits moderate the \\ relationship between treatment need \\ and OHRQoL. \\ \end{tabular} \\ \hline \hline \begin{tabular}{c} 300 adolescents and young adults \\ aged 15–20 years divided into \\ untreated and treated groups \\ (150 each). \\ \end{tabular} & Personality traits evaluation with NEO-FFI. & \begin{tabular}{c} Attitude, personality traits, and pain \\ perception significantly influence patient \\ cooperation and the success of orthodontic \\ treatment. \\ No significant difference in pain \\ perception was found between treated and \\ untreated groups or between genders. \\ Higher levels of neuroticism are \\ associated with increased pain perception, \\ while conscientiousness is directly \\ proportional to pain perception. \\ \end{tabular} \\ \hline \hline \begin{tabular}{c} 38 adolescents aged 9–12 years. \\ (2017) [59] \\ \end{tabular} & \begin{tabular}{c} Patient temperament and personality \\ traits assessment by the EAS-C \\ Temperature Questionnaire, Generalized \\ Self-Efficacy Scale (GSES), NED-FFI, and \\ Parental Attitude Scale. \\ \end{tabular} & \begin{tabular}{c} Psychological traits such as high \\ self-efficacy, conscientiousness, and strict \\ parental requirements positively correlate \\ with better compliance in wearing \\ removable orthodontic appliances. \\ Psychological assessments can predict \\ patient compliance, suggesting their \\ potential use in planning \\ orthodontic treatments. \\ \end{tabular} \\ \hline \hline \begin{tabular}{c} 230 adolescents aged 11–14 years \\ (mean age 12.48 years). \\ \end{tabular} & \begin{tabular}{c} Personality traits assessment by BPTI. \\ Personality traits assessment by BPTI. \\ Personality traits assessment by BPTI. \\ Treatment need and oral health-related \\ quality of life in adolescents. \\ Adolescents with higher levels of \\ extraversion and openness to experience \\ are less negatively affected by their \\ orthodontic treatment needs. \\ \end{tabular} \\ \hline \hline \
\begin{tabular}{c} 50 adults aged 18–48 years (mean \\ age 27.62 years). \\ \end{tabular} & Personality assessment by NEO-FFI. &
\begin{tabular}{c} Females experienced a significant \\ reduction in negative oral health impacts \\ after Invisignal treatment \\ Among males, personality traits such as \\ openness, extraversion, and \\ constituiness predicted oral health \\ impacts after treatment. \\ Personality traits did not predict oral \\ health impacts for females. \\ \end{tabular} \\ \hline \end{tabular}
\end{table}