Effect of root surface treatment with denusomab after delayed tooth replantation.

Abstract

To evaluate denosumab, a human monoclonal antibody that mimics the effects of osteoprotegerin in bone metabolism, as a topical treatment of root surface to be used prior to delayed tooth replantation. Thirty-six rats' right incisors were used. Teeth were extracted and divided into: delayed replantation without root surface treatment (control); delayed replantation with root surface treatment with denosumab 60mg/mL and 30mg/mL, respectively, for 10min both experimentals groups. After that, the root canals were filled with calcium hydroxide and replanted. After 15 and 60days, the animals were euthanized, and the samples were collected and processed for microscopic analysis. Histological sections were performed, and stained with HE to describe the dental characteristics, measure ankylosis, replacement resorption, and dental resorption by conventional microscopy. Also, was performed Brown & Brenn staining and immunohistochemistry for RANKL, OPG, and periostin. Denosumab 60mg/mL reducted ankylosis (p < 0.0001), replacement resorption (p < 0.0001), and tooth resorption, 60days after replantation, compared to untreated replanted teeth (p < 0.005). Lower bacterial contamination in root surface in the denosumab treatment groups was found, regardless of the concentration used (p < 0.001). Also, denosumab treatment inhibited the expression of RANKL without modulating OPG. Periostin was observed in periodontal ligament of replanted tooth, although this labelling was absent in the ankylosis areas, in both experimental periods. Treatment of the root surface with denosumab at 60mg/mL of rat teeth before delayed replantation reduced dental root resorption compared with the untreated teeth after 60days. Survival of a replanted tooth has been a challenge in clinical practice. The use of a medication, such as denosumab, to limit dental root resorption represents an important therapeutical approach.