27 In mTOR inhibitor review addition, this study confirms that sagittal sections of the hemi-arch give a more reliable determination of the major diameter of the periapical lesion extension.19 Ideally, the area of the periapical lesions of the studied root canals should be compared with tomographic baseline images taken before and after the induction procedure.27 However, technical limitations for positioning the head of the animals in the I-CAT device and potential movement with subsequent distortion during the scanning discarded this analysis. Regarding the low success rate found in the endodontically treated teeth,

the results could be explained by the poor microbial control of the selected protocol that includes the lack of intracanal medication. Leonardo et al.28 showed that even intentional enlargement of the apical foramen of infected root canals treated in a single appointment was not followed by a higher degree of repair in comparison with root canals treated with calcium hydroxide. Borlina et al.29 showed that for Sealer 26 and endomethasone sealers, the widening of the apical foramen favored healing after the use of calcium hydroxide. Interestingly, in this work, the area of periapical

destruction was Trichostatin A nmr restricted to 1.12 to 3.43 mm2 when periapical radiographs were used, showing that endodontically treated tooth lesions could be more restricted to the narrow bone in comparison with the nontreated roots. These results are in agreement with the results of previous studies22 and 28 and were confirmed using volumetric data. In fact, the goal of endodontic treatment is not only to eliminate bacteria, but also their toxins. Previous studies in animals have shown the ability of calcium hydroxide to neutralize endotoxins in necrotic root canals.30 and 31 Clinically, it appears that endodontic treatment still should be limited to protocols with well-documented histologic success.32 and 33 The void created by new PAK6 diagnosis technology (CBCT) emphasizes the necessity of well-controlled clinical studies so as to establish the success rate and limitations of nonsurgical endodontic treatment. The same can

be applied to the use of intracanal medication when the diagnosis of necrotic pulp and chronic apical periodontitis is present. Despite the advantages of sagittal sections to evidence apical periodontitis, the selection of the slice with the largest periapical bone destruction in this study can overestimate the actual bone loss because it did not take the 3-dimensional change into consideration. As with other studied techniques, subjectivity of the evaluator may confound the data obtained because tracing of the periapical lesion on the slices using OsiriX software is still dependent on the accuracy of the examiner. However, OsiriX software is a free open-source software that can help to encourage future CBCT volumetric studies.