[Experimental establishment of animal model of temporomandibular joint ankylosis secondary to condylar sagittal fracture].

OBJECTIVE

To experimentally develop an animal model of traumatic temporomandibular joint ankylosis secondary to condylar fracture in small Tail Han sheep.

METHODS

Four sheep were used to make sagittal fracture of condyles. The cartilage layer of articular surface was damaged and lateral half of articular disc was removed in the right side and conserved in the left side as a control. All animals were sacrificed at the end of 6 months postoperatively. CT observation and histological examination were carried out to evaluate the formation of ankylosed joints.

RESULTS

All of the animals showed a change of mixed ankylosis on the right sides. On the CT image, the joint space became narrow and the articular surfaces became irregular with high-density callus formation. Histological observation validated that the bone-like and the cartilage-like matrix scattered between the condyle and temporal fossa. The ankylosis bone bridge could be figured out in some slices.

CONCLUSION

This study has successfully simulated the formation of temporomandibular joint ankylosis resulting from condylar fractures. The established ankylosis model is allowed to duplicate at a high successful rate.