[The value of cone beam computed tomography in detecting suspicious vertical root fractures of molars on periapical radiographs].

OBJECTIVE: To evaluate the diagnostic accuracy of the cone beam computed tomography (CBCT) in detecting suspicious vertical root fractures (VRF) of molars on periapical radiography. METHODS: Forty-five teeth of 45 patients with clinical signs and symptoms suggestive of VRF but not confirmed by periapical radiographs were collected. All of these 45 teeth accepted the examination of CBCT and were extracted for conceivable bad prognosis. All these teeth were extracted by minimally invasive surgery, and the conditions of the roots were observed to make sure the VRF happened or not before extraction. Nine teeth were excluded post operation because of fragmented and horizontal root fracture. Thirty-six teeth were included in this study. Two dentists observed the CBCT images of the teeth independently and reached a consensus. Diagnosis test was performed in this study. RESULTS: The sensitivity, specificity, and accuracy of the CBCT in detecting VRF were 72.4%, 91.8% and 84.6%. The positive predictive value and negative predictive value and Youden index were 84.0%, 84.9% and 0.642 respectively. CONCLUSIONS: CBCT should be used in diagnosing VRF in those cases which could not be confirmed by clinical signs, symptoms and periapical radiographs. But for those cases with metal restorations were not recommended for further CBCT examination.