Análise fractal de lesões periapicais de origem inflamatória por meio de tomografia computadorizada de feixe cônico

Abstract

The development of apical periodontitis is associated with infection by microorganisms and migration of their subproducts through the root canal system to the periapical region, where they induce an inflammatory response that can be seen on tomographic images as hypodense, circumscribed image, associated with the root apex, which may or may not demonstrate a surrounding radiopaque halo. Fractal analysis (FA) is a quantitative method capable of describing the structural pattern of complex geometric shapes, being expressed numerically as fractal dimension (FD). The higher the DF value, the more complex is the evaluated structure. Differential diagnosis between apical lesions is still preferentially given by histopathological examination. The aim of this study was to assess FA as a differential diagnostic predictor method between periapical cysts and granuloma in cone beam computed tomography (CBCT) exams. Twelve patients were selected, including 6 with a histopathological diagnosis of periapical cyst and 6 with a diagnosis of periapical granuloma, who had CBCT exams in the analysed databases. Images were standardized and analysed using the Fiji software and the FD of each lesion was determined with the aid of the BoneJ plugin. The cutoff point for differentiation of lesions was determined for the two groups analysed: group I with standard number of slices and group II with maximum number of slices encompassing the lesion. The results showed that periapical cysts and granulomas affect both genders similarly and are more prevalent between the third and sixth decades of life. For group I, the FD value for the cutoff point between lesions was 2.09 and for group II the value was 2.28, since values below the cutoff point were representative for periapical cyst. FA was considered a useful and non-invasive diagnostic tool to distinguish between apical periodontitis.