Coronoidoplasty in TMJ ankylosis treatment

Abstract

A 2-year-old boy was brought by his parents with complaints of difficulty in mouth opening for the past one and half years. He had difficulty in chewing and was malnourished, with developing facial asymmetry. He was diagnosed with right side temporomandibular joint ankylosis. We planned for surgical removal of the ankylotic mass. But we modified the treatment protocol. Instead of doing coronoidectomy after aggressive excision of the ankylotic mass as advocated by Kaban, we did a 'coronoidoplasty' after aggressive excision of the ankylotic mass. Coronoidotomy or coronoidectomy is one of the rungs in the treatment ladder that is followed in surgical management of temporomandibular joint ankylosis. But one of the postoperative complications after coronoidectomy is the open bite. The difficulty to close the mouth becomes more pronounced when bilateral coronoidectomy is done. However, 'coronoidoplasty', as we have done for this patient retains the action of the temporalis muscle on the mandible in closing the mouth, yet removes the mechanical interference of the coronoid process. Postoperatively the patient was able to clench his teeth well, chew properly and there was no open bite.

Keywords: dentistry and oral medicine; oral and maxillofacial surgery.

Figure 1

Preoperative frontal view.

Figure 2

Preoperative right lateral view.

Figure 3

Preoperative left lateral view.

Figure 4

Osteotomy through submandibular incision.

Figure 5

Osteotomy through preauricular incision.

Figure 6

Securing coronoid before osteotomy.

Figure 7

Segment of resected ascending ramus.

Figure 8

Coronoidoplasty fixation.

Figure 9

Resected ankylotic mass and ramus.

Figure 10

Immediate post Operative.

Figure 11

Immediate post-OP opening.

Figure 12

Seventh day post OP.

Figure 13

Mouth opening seventh day post OP.

Figure 14

Mouth opening close to 6 months post OP.

Figure 15

Deviation to the right side but adequate opening.

Figure 16

Mouth opening adequate to protrude tongue.

Figure 17

Frontal view mouth closed.

Figure 18

Healing with minimal scarring.

Figure 19

Direction of masseter and temporalis muscle fibres. This illustration was drawn by the author (DSSS).

Figure 20

Direction of pull. Copyright by AO Foundation, Switzerland. Source: AO Surgery Reference, https://surgeryreference.aofoundation.org.

Figure 21

Postoperative frontal view.

Figure 22

Postoperative right lateral view.