Periradicular Regeneration after Endodontic Surgery with Calcium-enriched Mixture Cement in Dogs

Introduction: The aim of this in vivo study was to compare the response of periradicular tissues to mineral trioxide aggregate (MTA) and calcium-enriched mixture (CEM) cement as root-end fillings and to analyze hard tissue healing after periradicular surgery. Methods: Intentional periradicular lesions were induced in 32 premolar teeth in 4 beagle dogs. The root canals were prepared, dried, and obturated with laterally condensed gutta-percha with sealer, and the coronal access cavities were filled with amalgam. After surgical exposure of the apices, 2-3 mm of the apical root was resected, and root-end cavities were ultrasonically prepared. The root-end cavities were randomly filled with MTA or CEM cement. After 2 months, the animals were killed; tissue blocks were removed and prepared for histologic examination. Hard tissue healing including cementum and new bone formation in addition to concentration and extent of inflammation were evaluated. Results: Eight samples were excluded. The major finding was the cementum deposition adjacent to MTA in 11 of 12 samples and CEM cement in 10 of 12 samples. With one-way analysis of variance, no significant difference was observed between the periradicular tissue response to tested materials. Conclusions: CEM cement and MTA were associated with regenerative periapical tissue response when used as root-end filling biomaterials. (J Endod 2010;36:837-841)