Idiopathic Condylar Resorption: Analysis Of Outcomes Following Total Joint Replacement
Idiopathic Condylar Resorption: Analysis Of Outcomes Following Total Joint Replacement
Friday, September 14, 2012: 9:30 AM
Statement of Problem: Idiopathic condylar resorption (ICR) continues to present a major diagnostic and therapeutic challenge to practitioners for many reasons including rarity of the condition, progressive nature of the deformity, and its simultaneous involvement of skeletal, occlusal and articular disorders. Recommended treatment alternatives range from no surgery, only orthognathic surgery (maxillary impaction and chin camouflage surgery), staged TMJ and orthognathic surgery, to concomitant TMJ and orthognathic surgery. Traditionally, costochondral grafts have been used for TMJ replacement in this sub-group of patients, but advances in technology and availability of modern, patient-fitted TMJ alloplastic replacement systems may offer many benefits over such autogenous replacement options.
Materials and Methods: A retrospective analysis of all patients who underwent surgical treatment of ICR by a single surgeon at Boston University Medical Center hospital between 2000 and 2008 was performed. Criteria for inclusion in the study included: 1) Progressive mandibular retrusion secondary to TMJ resorption, 2) negative screening for known forms of systemic arthrides causing TMJ resorption, c) Absence of any history of trauma, 4) Presence of anterior open bite with Class II skeletal and dental malocclusion, and, 5) Surgical treatment involving bilateral TMJ total joint replacement and concomitant mandibular advancement with or without maxillary surgery. Clinical and radiographic examination was performed presurgically (T1), immediately postsurgery (T2), and at longest follow-up (T3). Visual analog scales were used for subjective examination of jaw function, dietary restrictions, functional disability, patient satisfaction, and pain at each of the above intervals. Objective examinations included: a) clinical evaluations of TMJ sounds, anterior open bite, occlusal relationship, mandibular range of motion (excursions, protrusion, and maximum opening), cranial nerve VII injury, and objectionable scarring, and, b) radiographic analysis by superimposition of cephalometric tracings for measurement of surgical change (T2-T1) and relapse (T3-T2).
Results: A total of 21 patients were included in the study. The average patient age was 25.6 years (range 22 - 32) and average follow up was 3.4 years (R 2-8). All patients were females. 10/14 (70%) patients correlated the period of active orthodontic treatment to the initiation of resorption. All patients gave a history of clicking/popping of their TMJ’s at some stage during their lifetime. Average surgical time was 8.5 hours (R 5.5-9) and the average duration of hospitalization was 2.6 postsurgical days (R 2-5). Average mandibular advancement at Point B was 18.9 mm (R 14-27) and average occlusal plane change was -6.8 degrees (R 3-8). 16/21 (76%) underwent maxillary orthognathic surgery for posterior downgrafting with rigid fixation and grafting. One patient had prolonged weakness of the frontal/temporal branch, which resolved completely in 7 months. Long-term follow-up revealed excellent stability of surgical movements with significant decrease in TMJ and myofascial pain, headaches, and dietary restrictions.
Conclusions: ICR patients can be treated very effectively using patient-fitted TMJ total joint prostheses for correction of TMJ resorption and mandibular advancement in combination with maxillary orthognathic surgery, when indicated for correction of the associated dentofacial deformity. Use of these prostheses eliminates donor site morbidity and allows for extremely large mandibular advancements to be performed in a predictable manner with a drastic reduction in TMJ dysfunction symptoms and excellent stability of orthognathic movements.
Materials and Methods: A retrospective analysis of all patients who underwent surgical treatment of ICR by a single surgeon at Boston University Medical Center hospital between 2000 and 2008 was performed. Criteria for inclusion in the study included: 1) Progressive mandibular retrusion secondary to TMJ resorption, 2) negative screening for known forms of systemic arthrides causing TMJ resorption, c) Absence of any history of trauma, 4) Presence of anterior open bite with Class II skeletal and dental malocclusion, and, 5) Surgical treatment involving bilateral TMJ total joint replacement and concomitant mandibular advancement with or without maxillary surgery. Clinical and radiographic examination was performed presurgically (T1), immediately postsurgery (T2), and at longest follow-up (T3). Visual analog scales were used for subjective examination of jaw function, dietary restrictions, functional disability, patient satisfaction, and pain at each of the above intervals. Objective examinations included: a) clinical evaluations of TMJ sounds, anterior open bite, occlusal relationship, mandibular range of motion (excursions, protrusion, and maximum opening), cranial nerve VII injury, and objectionable scarring, and, b) radiographic analysis by superimposition of cephalometric tracings for measurement of surgical change (T2-T1) and relapse (T3-T2).
Results: A total of 21 patients were included in the study. The average patient age was 25.6 years (range 22 - 32) and average follow up was 3.4 years (R 2-8). All patients were females. 10/14 (70%) patients correlated the period of active orthodontic treatment to the initiation of resorption. All patients gave a history of clicking/popping of their TMJ’s at some stage during their lifetime. Average surgical time was 8.5 hours (R 5.5-9) and the average duration of hospitalization was 2.6 postsurgical days (R 2-5). Average mandibular advancement at Point B was 18.9 mm (R 14-27) and average occlusal plane change was -6.8 degrees (R 3-8). 16/21 (76%) underwent maxillary orthognathic surgery for posterior downgrafting with rigid fixation and grafting. One patient had prolonged weakness of the frontal/temporal branch, which resolved completely in 7 months. Long-term follow-up revealed excellent stability of surgical movements with significant decrease in TMJ and myofascial pain, headaches, and dietary restrictions.
Conclusions: ICR patients can be treated very effectively using patient-fitted TMJ total joint prostheses for correction of TMJ resorption and mandibular advancement in combination with maxillary orthognathic surgery, when indicated for correction of the associated dentofacial deformity. Use of these prostheses eliminates donor site morbidity and allows for extremely large mandibular advancements to be performed in a predictable manner with a drastic reduction in TMJ dysfunction symptoms and excellent stability of orthognathic movements.