Overjet and Overbite Influence on Cyclic Masticatory Movements: A CT Study

Aim. To determine whether a relationship exists between the linear measurements of overjet and overbite and the interincisal space delimited by the morphology of the upper and lower incisors. Method and Materials. 30 subjects (age range from 14.1 to 34.8 years, with a median age of 23.5 years and sex ratio F/M: 5/10) with overjet and overbite equal to 2 mm were selected from a group of 381 individuals with a full and well-aligned dentition, no previous dental treatment, and no signs or symptoms indicative of temporomandibular disorder. Computed Tomography images of vinyl polysiloxane impressions of the 30 subjects' anterior teeth were acquired. The interincisal space was defined as Immediate Overjet Angle and was calculated on the Computed Tomography images. Results. Although the 30 subjects presented overlapping measures of overjet and overbite, the values of the Immediate Overjet Angles were different in a range of a minimum value of 12° and a maximum value of 54°. Conclusion. This study reveals that (1) only 30 (7.9%) of the 381 individuals considered have values of overjet and overbite equal to 2 mm and (2) the Immediate Overjet Angle values of the 30 subjects are not related to the values of overjet and overbite.