Objective: This study was directed to evaluate the regenerative potential of simvastatin (SIM) on dental pulp stem cells (DPSCs) in non-vital immature dogs' teeth both histologically and radiographically.
Methods: The present study was carried out on 6 adult healthy male mongrel dogs aged from 4 to 6 months and their weight ranged from 12 to 17 kg. Three premolars (two rooted) in each quadrant were included in this study summing up the total number of teeth to 72 (12 premolars x 6 dogs). Endodontic access cavities were prepared in all experimental teeth in the buccal surface and the vital pulps of teeth were exposed till confirmation of radiolucency. Then triple antibiotic paste was used for disinfection of root canals for 3 weeks. After disinfection period, the teeth were divided into two groups: group 1; treated with dental pulp stem cells and simvastatin while group 2; was treated with dental pulp stem cells only. Both groups were evaluated histologically and radiographically after 1 week, 1 month and 3 months. Results: Better radiographic and histologic findings were found in the group treated with dental pulp stem cells with simvastatin than groups treated with dental pulp stem cells only after 1 week, 1 month and 3 months of evaluation periods. Conclusions: Under the condition of this study, simvastatin aids in regeneration of infected immature dog's teeth with the ability of producing functional dentin-pulp complex and inclusion of a stem cells seemed to improve the outcomes of attempted regeneration.