Three-dimensional assessment of temporomandibular joint in skeletal Class I malocclusion with variable degrees of overbite and overjet.

Objective: To three-dimensionally evaluate the position and morphology of the TMJ in skeletal Class I with variable degrees of overbite and overjet in comparison with normal peers.
Methods: Pretreatment CBCT scans of 126 adults were retrieved. Based on the severity of overjet and overbite, the sample was divided into three main groups and six subgroups (18 patients each): the first group with a normal overbite and variable overjet degree and the second group with normal overjet and variable overbite degree. These six subgroups were compared with a third control group of normal overjet and overbite.
Results: There were significant differences in vertical condylar position, vertical and anteroposterior condylar inclinations, condylar height, and significant posterior condylar positioning in severe deep overbite, compared with the control group.
Conclusion: There were significant changes in the TMJ components in severe deep overbite cases. Therefore, sever deep overbite could be considered a predisposing factor for temporomandibular disorders.