A radiographic study of the effect of various retrograde fillings on periapical healing after replantation.

ABSTRACT

An effective retrograde sealing procedure places great demands upon both technique and materials. Prevention of micro-leakage, biocompatibility and stability of the material in the apical tissues are very important. To evaluate potential retrograde filling materials, a replantation model has been developed in which extracted permanent molars were replanted in monkeys after apicectomy of each root, preparation of a 2-mm deep retrograde cavity and its sealing with various dental materials. Prior to retro-filling the remaining pulp was exposed to saliva. Apicected molars which were infected and did not receive retrograde fillings served as positive controls. Periapical healing was evaluated radiographically after 8 weeks based on planimetric measurements of the size of the periapical radiolucency. The following dental materials were tested amalgam, glass ionomer cement, calcium-hydroxide lining cement, AH 26 root canal sealer, various zinc oxide-eugenol cements, Cavit, and gutta-percha with various sealers. The materials which were associated with better apical healing than the infected controls were glass ionomer cement, Cavit, and the zinc oxide-eugenol cements. When plain zinc oxide-eugenol or IRM were combined with a gutta-percha core, healing was best and not statistically different from normal apices. It was concluded that radiographic assessment at 8 weeks of molar teeth retrograde filled prior to replantation could be a valuable method for discrimination of potentially useful materials in vivo.