Influence of enhancement filters in apical bone loss measurement: A cone-beam computed tomography study

BACKGROUND The use of cone-beam computed tomography images (CBCT) providing a better assessment of bone injuries, although the sensibility of lesions measurement might be improved by the use of enhancement filters. Objective: This study aimed to analyze the influence of enhancement filters in apical bone loss measurement. MATERIAL AND METHODS Eighteen CBCT cases randomly selected of apical bone loss were evaluated. The analyses were carried out following the evaluation in axial, coronal and sagittal protocols, using enhancement filters as Hard, Normal, and Very Sharp. The variables were statistically analyzed by Friedman and Wilcoxon test, Spearman's rho, and intraclass correlation coefficient. RESULTS The differences between filters in axial and sagittal protocols were significant (p<0.05); however, this was not observed in the coronal slice. The use of Hard filter demonstrates better results than Very Sharp and Normal filter, improving significantly the bone loss measurement. A strong, significant and positive correlation was noted for all filters (with p< 0.001), such as a strong agreement between the variables, when the Normal filter was used as a reference. CONCLUSIONS The use of enhancement filters increases the sensitivity of alveolar bone loss measurement, with relative advantage for Hard filter. Key words:Cone-Beam computed tomography. endodontics. periapical periodontitis. image enhancement. alveolar bone loss.