Microscopic Evaluation of the Effect of Oral Microbiota on the Development of Bisphosphonate-Related Osteonecrosis of the Jaws in Rats.
OBJECTIVE
Osteonecrosis of the jaws is a side effect associated with the use of bisphosphonates. Using histologic analysis, this study aimed to evaluate the influence of microbial colonies in the development of osteonecrosis in the jaws of rats subjected to nitrogenous and non-nitrogenous bisphosphonates, undergoing surgical procedures.


METHODS
Thirty-four rats (Rattus norvegicus, Wistar strain) were allocated randomly into three groups: 12 animals treated with zoledronic acid; 12 animals treated with clodronate; and 10 animals treated with saline. Sixty days after the start of treatment, the animals underwent three extractions of the upper right molars. After 120 days of drug administration, the rats were killed. Histologic analysis was performed on specimens stained with hematoxylin and eosin by the technique of manual counting points using Image-Pro Plus software on images of the right hemimaxilla.


RESULTS
Osteonecrosis was induced in the test groups. There was no statistically significant association between the presence of microbial colonies and the presence of non-vital bone (Kruskal-Wallis, P > 0.05).


CONCLUSIONS
Use of zoledronic acid was associated with non-vital bone and the results suggested that the presence of microbial colonies does not lead to osteonecrosis.
Dental College, Federal University of Pelotas - UFPel, Rio Grande do Sul, Porto Alegre Brazil.
Felipe M
FM
Silveira
Dental College, Federal University of Pelotas - UFPel, Rio Grande do Sul, Porto Alegre Brazil.
Adriana
A
Etges
Dental College, Federal University of Pelotas - UFPel, Rio Grande do Sul, Porto Alegre Brazil.
Marcos B
MB
Correa
Dental College, Federal University of Pelotas - UFPel, Rio Grande do Sul, Porto Alegre Brazil.
Ana Carolina U
AC
Vasconcelos
bisphosphonate-associated osteonecrosis of the jaw; diphosphonates; infection