The association between clinical diagnostic factors and the prevalence of vertical root fracture in endodontic surgery

Background/Purpose: Diagnosis of vertical root fractures (VRFs) can often be challenging due to the similarity of signs and symptoms with other common dental infectious diseases. This study was aimed at evaluating the potential relationship between VRFs and commonly used clinical diagnostic factors. Methods: 330 root-filled teeth with endodontic failures were subjected to endodontic microsurgery over a six-year period. VRFs were identified in 61 teeth. A randomly age- and sex-matched retrospective case-control study was conducted on a subset of 59 root-filled teeth with VRFs (cases) and 177 root-filled teeth without VRFs (controls). The strength of association between preoperative signs and radiographic findings and VRFs was evaluated using logistic regression model. Results: Sinus tract, periodontal pocket depth ≥5 mm, periodontal swelling or abscess, and radiological image of J-shaped or “halo” radiolucency were significantly more frequent in cases than in controls (p < 0.05). With regard to logistic regression analysis, J-shaped or “halo” radiolucency demonstrated the greatest association with VRF, followed by periodontal pocket depth ≥5 mm, sinus tract, and periodontal swelling or abscess. Approximately 70% of cases manifested themselves as combinations of at least two of these factors. Teeth having two and three or four of these factors had 3.14 times and 11.64 times higher risks for the presentations of VRFs, respectively (p < 0.001). Conclusion: The major risk for VRFs was represented by those presenting radiological image of J-shaped or “halo” radiolucency, periodontal pocket depth ≥5 mm, sinus tract, and periodontal swelling or abscess simultaneously.