When ankylosed primary teeth are retained beyond the mixed-dentition stage and the involved teeth are below the occlusal plane, occlusal and interproximal contacts can be restored to esthetic and functional anatomic contours. With the development of new, improved posterior composite resins that have greater wear resistance and stronger adhesive bonding systems for enamel and dentin, new opportunities for conservative, simple, and efficient esthetic and functional restorations are possible in selected retained ankylosed primary molars.