Microscopic analysis of the effect of zoledronic acid on bone healing of dental alveoli of Wistar rats

Abstract

Zoledronic acid is a powerful bisphosphonate nitrogen. When deposited in bone tissue causes a decrease in bone reabsorption. Thus, these are drugs of choice for treating osteocytes diseases. However, the current increase in the prescription of bisphosphonates brought consequences with it, such as osteonecrosis of the jaws. The mechanism of action of bisphosphonates has not yet been fully clarified and the majority of published studies are case reports, retrospective studies or consensus on the management of this type of injury. Furthermore, there are few studies correlating the effects of these drugs with osteonecrosis of the jaw and the different actions of those in the oral cavity and other bone tissues. Objective: To investigate the changes caused by zoledronic acid on the metabolism of bone remodeling through quantitative and qualitative analysis of the bone healing process by conventional microscopy and by quantification of osteoclast apoptosis by TUNEL test. Material and methods: 24 male rats will be used at their 12th week of life which will be divided into 4 groups randomly: control group, Zoledronic acid group, Surgical Control group, Zoledronic acid Surgical group. Each group will have 6 rats and drug administration will be held intraperitoneally every 28 days in AZ and AZ surgical groups. 45 days after the beginning of the experiment the rats of the two surgical groups will be submitted to extraction of the superior molars on the right side. The euthanasia will be performed 150 days after the start of the experiment. The parts of the maxilla will be processed for histological study and stained with Herris' hematoxylin and Lision's eosin through TUNEL method. Histological images will be scanned, analyzed and counted in software. After obtaining the results and tabulating them, statistical comparison will be applied with 5% of significance level.