Background The conventional management of fibrous extracapsular temporo-mandibular joint (TMJ) ankylosis, a debilitating disease, is associated with surgical complications and financial burden on the patients. Objective To assess the outcome of conservative approach to the management of fibrous extracapsular TMJ ankylosis. Patients and methods This is a prospective study of patients who presented at the Dental and Maxillofacial Surgery Clinic of the University of Calabar Teaching Hospital, Nigeria, during the period from January 1999 to December 2012 with a history of inability to open the mouth diagnosed as fibrous extracapsular TMJ ankylosis. Results Twenty-one subjects were treated and their ages ranged from 11 to 22 years with mean at 15.0 years. There were 13 (61.9 %) males and 8 (38.1 %) females with male: female ratio of 1.6:1. The aetiological factor that predisposed to formation of extracapsular TMJ ankylosis was facial trauma. There was no facial asymmetry and the side distribution of the affliction showed that 1 (4.8 %) was bilateral while 20 (95.2 %) were unilateral. Eight cases (38.1 %) were incomplete ankylosis while the rest (n = 13, 61.9 %) were complete. The shorter the duration of fibrous ankylosis and the greater the initial inter-incisal distance before treatment, the better the treatment outcome. Conclusion The outcome of treatment suggests that the conservative approach to management of this condition was beneficial to these patients because they presented early. However, randomized controlled clinical trials are needed to validate this treatment option.