Factors Influencing Discrepancies Between Pre-Surgery Cone Beam Computed Tomography and Intraoperative Measurements in Apical Surgery.

Abstract

Introduction: This study evaluated the accuracy of cone-beam computed tomography (CBCT) in apical surgery planning by comparing preoperative CBCT measurements with intraoperative findings and identifying factors associated with discrepancies.

Methods: Ninety patients (107 teeth) scheduled for apical surgery underwent preoperative CBCT imaging using a Planmeca ProMax 3D Classic unit (90 kV, 10 mA, 100 μm voxel size, 5×5 cm FOV). Three calibrated examiners measured the apico-coronal and mesiodistal dimensions of buccal cortical bone perforations, as well as the apico-coronal length of the remaining buccal cortical bone plate (BCP) collar. CBCT measurements were compared to intraoperative measurements. Statistical analyses assessed associations between CBCT inaccuracies and variables including age, sex, lesion size, tooth type (anterior vs. posterior), location (maxilla vs. mandible), root canal status, and time interval between CBCT and surgery.

Results: A total of 101 surgical sites were analyzed. CBCT demonstrated a sensitivity of 90.6% and a specificity of 93.9% for detecting cortical plate perforations. Paired statistical tests revealed that CBCT significantly underestimated the mesiodistal dimension of lesions (P = .011) and overestimated the BCP collar dimension (P = .005). Multivariate generalized linear model (GLM) analysis indicated that larger lesion size, mandibular location, and the presence of a root filling were significantly associated with greater discrepancies.

Conclusion: CBCT demonstrates inherent limitations in measurement accuracy for apical surgery planning. Discrepancies are influenced by lesion size, tooth location, and root canal status. Clinicians should account for these factors when interpreting CBCT data to minimize preoperative planning errors.