Objective: To assess the dogs' tissue reaction to nHA-PA66 which is prepared to be used as a new root canal filling sealer.
Methods: The experimental apical periodontitis of dogs was induced first, then nHA-PA66 was used in the test groups while CCQ was used in the control group. The reactions of periapical tissues were measured by histological means.
Results: One month after nHA-PA66 was used in root canal filling, the dogs' periapical tissues showed mild to moderate inflammatory reactions, the X-ray films showed decreased radiolucent area as compared with the previous film. Three months later, tissue repairs occurred, which exhibited even more decreased radiolucent area on X-ray films. nHA-PA66 caused weak inflammatory reaction while the reparative reaction happened early.
Conclusion: nHA-PA66 has good tissue compatibility and is a potential sealer for root filling in clinical use.