Axiographic evaluation of mandibular mobility in children with angle Class-II/2 malocclusion (deep overbite)

Correction of the occlusion in Angle Class-II/2 patients is often more complicated and tedious than in Class-II/1 cases. Reasons given are the more comprehensive remodeling and functional adaptation processes of the temporomandibular joints (TMJ) since the articular tuberculum is more strongly developed in deep overbite, and a deep bite leading to a locked occlusion is dominant due to the steeper condylar path. Both characteristics are, however, considered to be the consequence of pronounced incisor retrusion. The present study covered 28 untreated Class-II/2 patients aged 8 to 12 years in whom functional TMJ adaptation to the retroclined maxillary incisors was studied with the help of electronic, 3D axiographic registrations of mandibular movements. Comparison with eugnathic age peers revealed increased mobility in mandibular protrusion and a somewhat steeper condylar path, although the latter was less pronounced than in adult patients. The results corroborate the concept of functional TMJ adaptation to incisor inclination and speak for early uprighting of maxillary incisors.