Mediation and moderation effect of the big five personality traits on the relationship between self-perceived malocclusion and psychosocial impact of dental esthetics

Objective was to explore the mediation and moderation effects of personality traits on the relationship between self-perceived malocclusion and psychosocial impact of dental esthetics. The sample included 252 subjects (62% female) aged 12-39 years. Self-perceived malocclusion was estimated using the 10-point scale Aesthetic Component of the Index of Orthodontic Treatment Need. The Psychosocial Impact of Dental Aesthetics Questionnaire was used to assess the psychological impact and the Big Five Inventory for personality traits. Moderation and mediation effects were evaluated with Pearson correlations and stepwise regression analysis, respectively. Self-perceived malocclusion ranged 1-8 and was the most significant predictor of psychosocial impact of dental esthetics, whose unique contribution accounted for 11-36.4% of variability, while age and sex account for 1.2-2.5% of variability. Personality traits have no mediation effect on this relationship. Moderation effect of agreeableness was present on the relationship between self-perceived degree of malocclusion and Social Impact (SI), Psychological Impact (PI) and Aesthetic Concern (AC) (ΔR2=0.035, 0.020 and 0.013 ; P<.001) while conscientiousness affected the relationship between perception of malocclusion and SI and PI (ΔR2=0.018 and 0.016 ; P<.05). In people with lower agreeableness and conscientiousness as opposed to those with higher, increasing severity of self-perceived malocclusion leads to lower increase of SI and PI. In people with lower agreeableness it influences AC in a similar manner. Extraversion, neuroticism and openness do not have a moderating effect. The relationship between self-perceived malocclusion and psychosocial impact of dental esthetics appears to be moderated and not mediated by the personality traits. Adolescents and young adults with lower agreeableness and conscientiousness as opposed to those with higher seem to be less affected by the increased severity of self-perceived malocclusion, demonstrated in reporting some psychosocial impacts