Change of condylar movements in using intermaxillary elastics

Abstract

I investigated the changes in condylar movements caused by intermaxillary elastics used in orthodontic treatment. The subjects included four adults (three males and one female) aged 23〜26 years (mean 24 years). All subjects had normal Class I occulusion with no signs or symptoms of temporomandibular disorder. Six degrees of jaw movement (three of translaton and three of rotation) were recorded and calculated using a Gnatho-Hexagraph at 20 mm jaw opening with and without Class II and Class III intermaxillary elastics. Class II elastics induced the condylar path to move forward. ClassIII elastics pushed it back and up, while increasing mandibular rotation. These results suggest that intermaxillary elastic force can affect condylar movements.