Association of horizontal and vertical overlap with prevalence of temporomandibular disorders

The aim of the study was to evaluate the relationship between horizontal (HO) and vertical overlap (VO) and prevalence of temporomandibular disorders (TMD) in a non-patient population. Out of the total number of subjects (230), 65.7% subjects were classified as asymptomatic, 5.7% subjects had muscle disorders (MD) (myalgia), 9.1% subjects had disc displacement with reduction (DDR), while 19.6% subjects had disc displacement with reduction associated with muscle disorder (DDR + MD) (myalgia). The HO equal to or greater than 5 mm was significantly more prevalent in the symptomatic patients (MD, DDR, DDR + MD) than in the asymptomatic group (P < 0.001). The VO equal to or > 5 mm also demonstrated statistically significant difference (P < 0.006) between the symptomatic (suffering from DDR, and DDR + MD) and asymptomatic subjects. Conclusion of the study is that the HO and VO equal to or > 5 mm was more present in the group of subjects with diagnosis of a TMD (DDR and MD), what distinguishes this group from the group of asymptomatic subjects.