Evaluation of the effect of cell sheet of human dental pulp stem cell, associated or not with photobiomodulation therapy, on repair of experimental condyle fracture in rats

Abstract

The repair of the condyle fracture (FC) with medial deviation occurs by the formation of bone callus and reorganization of the joint structures. Facial asymmetries may occur after conservative treatment of FC. Surgical intervention associated with tissue engineering and cell therapies, both mediated by stem cells (CTs), could be applied together with photobiomodulation therapy (PBMT) to seek fracture regeneration by improving treatment outcomes. The objective of this study will be to evaluate the effect of Cell Sheets (CSs) of human dental pulp stem cells (hDPSC), associated or not to PBMT, on the reapir of FC in rats. The study will have two steps: one in vitro (obtaining the CSs) and other in vivo (using an experimental model of FC). 96 Wistar rats, adult, males will be divided into four experimental groups with 24 specimens each. GI: FC with no additional treatment; GII: FC+PBMT; GIII: FC+CS involving the fracture line; GIV: FC+CS+PBMT. PBMT will be performed with infrared laser (780 nm, 40 mW, 0.04 cm2 beam area, 1 W/cm2, 3s, 3J/cm2, 0.12J per point) immediately, 48 and 96 hours after surgery. Animals body will be recorded. 7, 15, 30 e 90 days postoperatively (n=6) the animals will be sacrificed and the skull will be fixed and submitted to following analyzes morphometric in computerized microtomograph (MicroCT) histologic and histomorphometric (H&E), histochemistry (TRAP - tartrate resistant acid phosphatase) and immunohistochemistry (cell tracking-BrDU). The data will be analyzed statistically (± = 0.05). (AU)