This case report presents a 4 and 1/2-year-old boy suffered from toothache over lower right posterior area. After carefully differential diagnosis, #84 was treated with OD restoration as mean time #85 finished by Vitapex pulpectomy and OD restoration. Clinical and radiographic follow-ups were made 24 months after then. The OD restorations for these two teeth were still perfect, but both Vitapex and roots of #85 were gradually resorbed during these 2 years. We believe that further studies are necessary to evaluate the filling material for pulpectomy. (Taiwan J Pediatr Dent 2(4):121-125,2002)