Accuracy of CBCT with blooming artifact reduction filter on the measurements of dentin thickness in root canals with radiodense materials: an in vitro study.

The precision of dentin thickness evaluations in the presence of artifacts is vital, as inaccuracies may increase the risk of over-preparation and consequent structural damage to the tooth. The purpose of this in vitro study was to evaluate the accuracy of residual dentin thickness measurements in CBCT images of teeth with high-density intracanal materials, utilizing the blooming artifact reduction (BAR) filter. Twelve single-rooted human teeth were selected. Axial cuts were performed, and the root thickness was measured at the buccal, lingual, mesial, and distal surfaces, which represented the reference standard. CBCT scans were acquired of each specimen in 5 different settings: empty root canals (ERC), gutta-percha cone (GPC), gutta-percha and endodontic sealer (GPC + S), fiberglass post (FGP), and metal post (MP). Measurements were performed before and after the application of the BAR filter in the e-vol DX software. ANOVA with the Dunnet's post hoc test was used for comparison between measurements in CBCT images and the reference standard. The BAR filter did not influence the measurements in teeth with ERC, GPC, and FGP (p > 0.05). In teeth with GPC + S, the measurements with the BAR filter had no difference from the reference standard (p < 0.05). CBCT images measurements were comparable to the reference standard in the ERC, GPC, and FGP groups. BAR filter was restricted to the GPC + S group in the cervical third, and the MP group in the apical third. In root canals with metal posts, the overall dentin thickness was significantly underestimated in all CBCT images within the cervical and middle thirds.