Guided Access through Ceramic Crowns with Fiberglass Post Removal in Lower Molars: An In Vitro Study

Abstract

This in vitro study evaluated the accuracy of guided endodontics for the removal of intraradicular fiberglass posts from posterior mandibular teeth and the influence of the operator’s experience in this procedure. Forty root-filled mandibular first molars with an intraradicular fiberglass post were mounted onto 20 mandibular models. Guides for access were made following surface scanning and cone-beam computed tomography (CBCT) using CoDiagnostix software. The models were randomly divided between two operators (n = 20). One was an inexperienced dental surgeon (IN), and the other was a dentist experienced in the guided technique (EX). A postoperative CBCT scan was superimposed on the initial planning, and the means were calculated for the angle and for 3D deviation. The 95% confidence interval (CI) was calculated, and differences between groups were assessed by a t-test. The mean deviation angle was 2.54° (0–5.85°) for IN and 1.55° (0–2.85°) for EX. The mean 3D deviation was 0.44 mm (0.14–0.73 mm) for IN and 0.33 mm (0.11–0.76 mm) for EX. The means of the angle and 3D deviation were significantly different (p = 0.008 and p = 0.049). Guided endodontics was influenced by the operator and allowed access for removing intraradicular fiberglass posts with minimal deviation and greater accuracy for an experienced operator compared with an inexperienced one.

Post Removal Using Guided Endodontics: A Systematic Review of the Literature

“…Findings from this review showed that the use of guided endodontics is effective in the removal of dental posts with a low risk of iatrogenic errors. Complications were reported only in the two in vitro studies [29], [30]. Of those, the first one showed an 87.5% success rate and the second one 97.5%.…”

“…The effectiveness was measured by the reviewers as the ability to remove the dental post without causing severe complications such as a fracture or a perforation of the root. In all case reports the post was successfully removed with no complications (100% success rate) [22]- [28] In one in vitro study the post was removed from all but one tooth (97.5% success rate) where perforation occurred [29]. In the other in vitro study, the post was removed in 87.5% of the teeth, in one case it was unsuccessful because the drill bit hit the canal wall [30].…”

“…Only two studies reported the guide material being polymer resin [22], [30]. Five studies reported the dimensions of the guide sleeve [22], [23], [26], [29], [30]. All 9 studies included the removal of a fiber post.…”

“…On the other hand, 18 parameters were fulfilled by all case reports. Regarding the in vitro studies, one was assessed as a high risk of bias study, while the other one as a low risk of bias [29], [30]. Neither of the studies included a control group, and neither of the studies reported any blinding of the two operators.…”

Removal of fiber posts using conventional versus guided endodontics: a comparative study of dentin loss and complications

“…In addition, guided endodontics allows minimally invasive access to the apices during endodontic surgery [ 17 – 19 ]. A few case reports have shown that guided endodontics can be used to successfully remove fiber posts from root-filled teeth [ 20 – 26 ]. The accuracy of GE to provide access for the removal of intraradicular fiber posts was evaluated in an in vitro study of 40 teeth restored with fiber posts and composite cores, which showed that GE resulted in a mean apical deviation of 0.40 ± 0.19 mm [ 27 ].…”