Periapical lesions in primary and permanent human teeth: analysis of the correlation between radiographic lesion size and intensity of marking for beta-defensin 3

Abstract

The immune system acts directly on the immunopathology of the periapical lesion. Considering that ²-Defensin 3 is an endogenous antimicrobial peptide, that is, that participates in regulating the immune system, the objective of the present study will be to compare the radiographic size of periapical lesions of deciduous and permanent human teeth with the intensity of the marking for ²-Defensin 3 (hBD3). Root cysts of endodontic origin from caries lesions will be evaluated, being 15 primary teeth and 15 permanent teeth, obtained from the Laboratory of Pathology of the College of Dentistry of Ribeirão Preto of the University of São Paulo (FORP-USP), as well as the radiographs. Radiographic images will be transferred to the Image J 1.28 (National Institutes of Health - California - USA) program for measurement of the periapical radiolucent areas, in mm2. The periapical lesions will be submitted to histological processing and immunohistochemical analysis by the avidin-biotin-peroxidase complex method, to evaluate the immunostaining for ² -Defensin 3. The slides will be analyzed and photographed under an Axio Imager microscope. M1 (Carl Zeiss Microimagin GmbH, Gottingen, Germany), for further quantification of ²Defensin 3, at 400x magnification. Then, the correlation between the area of the periapical lesion in mm2 and the intensity of immunostaining for ²-Defensin 3 in deciduous and permanent teeth will be evaluated by means of appropriate statistical tests, with significance level of 5%.