Effect of Time Lapse on the Diagnostic Accuracy of Cone Beam Computed Tomography for Detection of Vertical Root Fractures

Diagnosis of alveolar and root fractures in macerated canine maxillae: a comparison between two different CBCT protocols

OBJECTIVES

To compare two small-field-of-view (FOV) CBCT protocols with different voxel sizes and number of frames for the diagnosis of root and alveolar fractures in macerated canine maxillae.

METHODS

80 incisor teeth from the canine species were inserted in 80 anterior alveolar sockets of 20 canine maxillae. An operator randomly divided each maxilla site (80 sites in total) into 4 equal groups of 20 sites: 1 (sound tooth and non-fractured alveolar socket); 2 (sound tooth and fractured alveolar socket); 3 (fractured root and non-fractured alveolar socket); and 4 (fractured root and fractured alveolar socket). The CBCT images were obtained using two different protocols: normal (N) (voxel 0.20 mm, 400 frames and radiation exposure 5.6 mGy) and high definition (HD) (voxel 0.15 mm, 500 frames and radiation exposure 7.0 mGy).

RESULTS

Sensitivity numbers for alveolar fractures were lower than specificity, resulting in comparable areas under the receiver operating characteristic curves (AUC) for both protocols. Sensitivity, specificity and AUC for N and HD protocols were very similar for root fractures. When comparing AUC for both N and HD protocols by submitting them to Student's t-test, the comparison among the curves produced statistically non-significant results for alveolar fractures and root fractures likewise.

CONCLUSIONS

Our findings demonstrated that the elected protocol for the diagnosis of root and alveolar fractures was N. This protocol allowed similar diagnosis results than HD protocol; however, with a lower amount of radiation exposure for the patient (5.6 mGy for N vs 7.0 mGy for HD).

Diagnosis of alveolar and root fractures: an in vitro study comparing CBCT imaging with periapical radiographs

Objective

To compare periapical radiograph (PR) and cone-beam computed tomography (CBCT) in the diagnosis of alveolar and root fractures.

Material and Methods

Sixty incisor teeth (20 higid and 40 with root fracture) from dogs were inserted in 60 anterior alveolar sockets (40 higid and 20 with alveolar fracture) of 15 macerated canine maxillae. Each fractured socket had a root fractured tooth inserted in it. Afterwards, each maxilla was submitted to PR in two different vertical angulation incidences, and to CBCT imaging with a small field of view (FOV) and high-definition protocol. Images were randomized and posteriorly analyzed by two oral and maxillofacial radiologists two times, with a two-week interval between observations.

Results

Sensitivity and specificity values were good for root fractures for PR and CBCT. For alveolar fractures, sensitivity ranged from 0.10 to 0.90 for PR and from 0.50 to 0.65 for CBCT. Specificity for alveolar fractures showed lower results than for root fractures for PR and CBCT. Areas under the ROC curve showed good results for both PR and CBCT for root fractures. However, results were fair for both PR and CBCT for alveolar fractures. When submitted to repeated measures ANOVA tests, there was a statistically significant difference between PR and CBCT for root fractures. Root fracture intraobserver agreement ranged from 0.90 to 0.93, and alveolar fracture intraobserver agreement ranged from 0.30 to 0.57. Interobserver agreement results were substantial for root fractures and poor/fair for alveolar fractures (0.11 for PR and 0.30 for CBCT).

Conclusion

Periapical radiograph with two different vertical angulations may be considered an accurate method to detect root fractures. However, PR showed poorer results than CBCT for the diagnosis of alveolar fractures. When no fractures are diagnosed in PR and the patient describes pain symptoms, the subsequent exam of choice is CBCT.