Temporomandibular joint (TMJ) ankylosis is a problem peculiar to India and Indian subcontinent. The patient develops many subsequent problems like nutritional deficit, aesthetic deformity due to interruption of growth and obstructive sleep apnea syndrome.

The treatment is release of ankylosis with creation of Gap or interposition of various autogenous or alloplastic materials. The loss of condylar cartilage, which is thought to be a growth center, is said to cause the cessation of mandibular growth in subsequent growing period in children who are operated in growing period. This results in asymmetry, retrognathia and sometimes problems of obstructive sleep apnea.

There are conflicting views whether the condyle is primary growth center or is the matrix of muscle around mandible, which again becomes functional after release induces growth. The functional matrix theory is well known. This confusion has led to growth center transplantation in the released condyle by either costochondral joint ( CCG) or sternoclavicular joint.

The aim of the study is to scientifically document the growth of mandible after release of TMJ ankylosis. The Gap arthroplasty proponents believe that the growth of mandible after release of ankylosis can catch up as a result of muscle matrix being functional again and the growth center transplantation school bases its assumptions on the condylar growth center theory.

There has never been any study on actual quantification of growth after Gap or costochondral (CCG) interposition arthroplasty. The growth reporting has largely been based on personal observations from case reports/ series. There have been conflicting reports in the literature about both and none have shown predictable growth.

The proposed research work will test the CCG arthroplasty and gap arthroplasty in a superiority trial and will help obtaining level-I evidence for growth center transplantation requirements in TMJ ankylosis. This will also establish which procedure has less recurrence associated with it.