Growth of the mandible after replacement of the mandibular condyle: an experimental investigation in Macaca mulatta.

PURPOSE

The study goal was to investigate growth of the mandible after temporomandibular joint reconstruction in juvenile monkeys.

MATERIALS AND METHODS

Sixteen juvenile monkeys (Macaca mulatta) were used as experiment subjects. Animals were equally divided into 4 experimental groups based on the method of temporomandibular joint reconstruction after bilateral condylar excision via extraoral vertical ramus osteotomies. Group Condyle animals had their condylar segments immediately replaced to serve as surgical controls. Group Bone animals were reconstructed with a bony strut. Group sternoclavicular joint (SCJ) animals were reconstructed with the sternal end of their clavicles. Group costochondral junction (CCJ) animals were reconstructed with costochondral junction of ribs. Standardized lateral cephalometric radiographs with the aid of tantalum bone markers were used to evaluate mandibular growth. Twenty animals were used as controls and were allowed to grow undisturbed for an 18-month period (Group Control).

RESULTS

All animals showed good mandibular function and a Class I molar relationship after an 18-month follow-up period. Statistical and graphic comparisons showed no significant difference in mandibular growth among any of the groups.

CONCLUSIONS

The results of this investigation suggest that, within the limits of this model, the choice of autograft for condyle replacement may be irrelevant.