Growth of the mandible after condylar reconstruction using transport distraction osteogenesis: an experimental investigation in goats.
BACKGROUND
Mandibular condyle damage during childhood disturbs mandibular growth and facial skeletal development. Transport distraction osteogenesis provides a new treatment for condyle reconstruction, but there are no data available on mandibular growth in growing individuals following surgery. The authors investigated the effect of condylar reconstruction by transport distraction osteogenesis on mandibular growth in goats.


METHODS
A condylar defect was created unilaterally in 44 growing goats. The animals were divided randomly into group A (n = 22) and group B (n = 22). Transport distraction was used to reconstruct the condyles in group A, whereas group B served as sham controls. Three-dimensional computed tomographic imaging was performed at different intervals. Ten animals from each group were used for mandibular growth measurements at 48 weeks after the end of distraction. Four animals from each group were euthanized at 12, 24, and 48 weeks after surgery. Their transport disks were harvested and processed for histologic evaluation.


RESULTS
In group A, the hemimandible of the distracted side exhibited similarities to the contralateral side except for the larger neocondyles. In group B, ramus height and width were significantly shorter on the undistracted side than on the contralateral side; concomitantly, there was mandibular deviation to the operated side. Well-organized fibrocartilage was seen at the neocondylar surface over time in group A but not in group B.


CONCLUSIONS
This study suggests that a neocondyle reconstructed by means of transport distraction has the potential to grow under functional stimuli of the temporomandibular joint. Therefore, this technique may serve as an alternative method for condylar reconstruction in growing individuals.
Zhu
Song-Song
SS
Chengdu, China From the State Key Laboratory of Oral Diseases, Sichuan University, and the Department of Oral and Maxillofacial Surgery, West China College of Stomatology, Sichuan University.
Hu
Jing
J
Ying
Bin-Bin
BB
Li
Ji-Hua
JH
D000818:Animals; D002508:Cephalometry; D006041:Goats; D007091:Image Processing, Computer-Assisted; D021621:Imaging, Three-Dimensional; D008297:Male; D008334:Mandible / Q000000981:diagnostic imaging / Q000254:growth & development* / Q000473:pathology; D008335:Mandibular Condyle / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D019857:Osteogenesis, Distraction / Q000379:methods*; D013704:Temporomandibular Joint / Q000000981:diagnostic imaging / Q000473:pathology / Q000502:physiology; D014057:Tomography, X-Ray Computed