Vertical root fractures and cracked teeth: post-endodontic root dentinal status through micro-CT assessment after ex vivo fiber post removal.

Objectives: This study aimed to investigate cracked teeth and vertical root fracture observable on micro-CT images of extracted roots of mandibular incisors, after fiber post removal.

Materials and methods: Thirty mandibular incisors were selected with any degree of slight incisal wear inspected with the aid of a stereomicroscope under 12x magnification, in order to have a group of young adult specimens according to the criteria of Hugoson et al. A sample of twelve mandibular incisors were selected, aged between 20 and 30 years old, with similar dentine volume and thickness. The specimens were scanned in a micro-computed tomography (micro-CT) device and submitted to root canal shaping, root canal filling, post space preparation, post placement and post removal.

Results: From a total of six experimental endodontic timepoints until post removal of 12 mandibular incisors, 64,800 cross-sectional images were analyzed and no vertical root fracture (VRF) or cracked tooth were detected.

Conclusions: Micro-CT assessment after ex vivo fiber post removal did not detect vertical root fracture or cracked tooth formation in the root canal walls of mandibular incisors.

Clinical relevance: This study highlighted that fiber post removal per se was not able to propagate VRF or cracked tooth formation or promoted any interruption of the integrity of human root dentin.