SEVERE RESTRICTION IN JAW MOVEMENT AFTER ROUTINE INJECTION OF LOCAL-ANESTHETIC IN PATIENTS WHO HAVE FIBRODYSPLASIA OSSIFICANS PROGRESSIVA

Objective. To determine the relationship of dental procedures to immed iate ossification and ankylosis of the jaw in patients who have fibrod ysplasia ossificans progressiva. Study design. A mail survey was condu cted of the 60 patient-members of the International Fibrodysplasia Oss ificans Progressiva Association. All 41 patients (18 males, 23 females ) who responded were examined. instantaneous exact hazard rates for os sification of the jaw were calculated by the Weibull model. Results. T hirty-six patients had dental procedures performed. Twenty-one (58%) p atients had received an injection of local anesthetic. Five (24%) pati ents had an immediate flare-up of fibrodysplasia ossificans progressiv a with ossification and permanent ankylosis of the jaw (expected occur rence, 0.031; p < 0.0001). None of the 12 patients who had comparable dental work without injections developed heterotopic ossification (exp ected occurrence, 0.019; not significant). Conclusion. Injections of l ocal anesthetic during dental procedures pose serious and immediate ri sk for inciting heterotopic ossification and ankylosis of the jaw in p atients who have fibrodysplasia ossificans progressiva and should be a ssiduously avoided.