Condyle-preserved arthroplasty versus costochondral grafting in paediatric temporomandibular joint ankylosis: a retrospective investigation

We aimed to evaluate results of condyle-preserved arthroplasty and costochondral grafting in growing children with temporomandibular joint ankylosis through medium-term follow-up and three-dimensional metric analysis. We assessed 11 patients (14 sides) with type II ankylosis (group A) and 11 patients (13 sides) with type III/IV (group B) from January 2012 to December 2015. Group A patients received condyle-preserved arthroplasty and group B patients received costochondral grafting. Postoperative computed tomography was used to measure condylar height, condylar width, mandibular ramus height and mandibular body length. Changes in maximum mouth opening were evaluated >1 year postoperatively.Postoperative follow-up showed similar average maximum mouth opening and one case of recurrence in each group. Computed tomography measurements showed that condylar width and mandibular ramus height increased in both groups A and B (P < 0.05). Moreover, in group A, condylar angulation of medially displaced malformation decreased by 13.2° (P < 0.05), and mandibular body length increased by 5.7 mm (P < 0.05). Thus, both condyle-preserved arthroplasty and costochondral grafting were effective surgical methods for treatment of temporomandibular joint ankylosis. Moreover, compared with group B, group A patients manifested more remarkable mandibular growth, at least in the anteroposterior direction of the mandibular body.