Does apical root resection in endodontic microsurgery jeopardize the prosthodontic prognosis?

Abstract

Apical surgery cuts off the apical root and the crown-to-root ratio becomes unfavorable. Crown-to-root ratio has been applied to periodontally compromised teeth. Apical root resection is a different matter from periodontal bone loss. The purpose of this paper is to review the validity of crown-to-root ratio in the apically resected teeth. Most roots have conical shape and the root surface area of coronal part is wider than apical part of the same length. Therefore loss of alveolar bone support from apical resection is much less than its linear length.The maximum stress from mastication concentrates on the cervical area and the minimum stress was found on the apical 1/3 area. Therefore apical root resection is not so harmful as periodontal bone loss. Osteotomy for apical resection reduces longitudinal width of the buccal bone and increases the risk of endo-perio communication which leads to failure. Endodontic microsurgery is able to realize 0 degree or shallow bevel and precise length of root resection, and minimize the longitudinal width of osteotomy. The crown-to-root ratio is not valid in evaluating the prosthodontic prognosis of the apically resected teeth. Accurate execution of endodontic microsurgery to preserve the buccal bone is essential to avoid endo-perio communication. (Restor Dent Endod 2013;38(2):59-64)

Effect of length of apical root resection on the biomechanical response of a maxillary central incisor in various occlusal relationships

“…, Cho & Kim ). However, the coronal root surface area is greater than the apical region of the same length (Cho & Kim ). As a consequence, the CRR value based on periodontal bone loss is not applicable to apically resected teeth (McGuire ).…”

“…(), for teeth with a healthy periodontium, 3 mm of apical root resection appeared to be mechanically acceptable. However, occasionally more extensive root resection is required clinically due to complications such as perforations, resorptions and root fracture (Cho & Kim ). According to previous studies, deep overbites and increased overjets are correlated with a greater rate of external apical resorption in maxillary incisors (Martins et al .…”

“…Classically, 1 : 1.5 to 1 : 1 of CRR is suggested as the acceptable value for bridge (fixed partial denture) abutments (Jang et al 2014). Most studies that have investigated the change in CRR mainly targeted the teeth with periodontal disease, because periodontitis is the main cause of an unfavourable CRR (Eke et al 2012, Cho & Kim 2013. However, the coronal root surface area is greater than the apical region of the same length (Cho & Kim 2013).…”

“…Most studies that have investigated the change in CRR mainly targeted the teeth with periodontal disease, because periodontitis is the main cause of an unfavourable CRR (Eke et al 2012, Cho & Kim 2013. However, the coronal root surface area is greater than the apical region of the same length (Cho & Kim 2013). As a consequence, the CRR value based on periodontal bone loss is not applicable to apically resected teeth (McGuire 1991).…”

Mid‐term outcomes and periodontal prognostic factors of autotransplanted third molars: A retrospective cohort study

“…26 Therefore, despite similar C:R ratios, considerable discrepancies in tooth stability exist between periodontally compromised teeth and teeth without fully developed roots or resected apices. 27 Owing to disagreement and ambiguity, heterogeneity in success rates is not exclusively related to disparate clinical outcomes but also to the specific definitions applied for evaluation. Hereby, the importance of consensus on the success criteria for autotransplanted teeth, beyond tooth loss, would be advantageous to facilitate research standardization and interpretation.…”