CBCT Patterns of Bone Loss and Clinical Predictors for the Diagnosis of Cracked Teeth and Teeth with Vertical Root Fracture

Abstract

Introduction: This study aimed to identify clinical and radiographic characteristics of teeth with longitudinal fractures to assist in the diagnosis and differentiation between cracked teeth and teeth with vertical root fracture (VRF).

Methods: Ninety-five patients (95 teeth) diagnosed with a longitudinal fracture (only cracked teeth or VRF) through clinical visualization of the fracture line were included in this study. Clinical and radiographic data were collected from the patients' records to identify the characteristics associated with each condition. Fifty-four patients (54 teeth) had full radiographic (periapical [PA] radiography and a cone-beam computed tomographic [CBCT] scan) and clinical findings (probing depths and clinical images of the fracture line). PA and CBCT images were evaluated by 2 independent examiners to identify the different patterns of bone loss associated with these teeth (no defect, an angular defect, a J-shaped defect, or a combined defect). Cohen kappa analysis was used to compare the results between the 2 examiners and between the findings of the PA and CBCT images. Pearson chi-square analysis, the Fisher exact test, and adjusted Bonferroni post hoc testing were used to establish an association between the type and extension of the longitudinal fracture with the probing depth, the CBCT pattern of bony defects, and the presence/absence of the buccal plate and also to compare the clinical and radiographic characteristics of cracked teeth and teeth with VRF (P < .05).

Results: CBCT images had 4.4 times the odds of detecting bony defects suggestive of longitudinal fractures compared with PA radiographs. Teeth with VRF were more associated with indirect restorations, deep probing (>6 mm), absence of the cortical plate, and a J-shaped defect on the CBCT image (P < .05). On the other hand, cracked teeth were associated with direct restorations, shallow probing (<6 mm), an intact cortical plate, and the presence of an angular defect on the CBCT image (P < .001). There was a significant correlation between a radicular extension of the fracture line and deep probing as well as J-shaped defects (P < .05).

Conclusions: Patterns of bone loss on CBCT imaging can likely differentiate between cracked teeth and teeth with VRF. The presence of an angular defect may suggest the presence of a crack in the tooth before intervention. J-shaped defects, deep probing (>6 mm), and loss of the cortical plate are likely suggestive of VRF.

Keywords: Angular defects; J-shaped lesions; cone-beam computed tomography; cracked tooth; vertical root fracture.