Diagnostic accuracy of panoramic and Cone Beam Computed Tomography (CBCT) radiographs showing bone dimensions in comparison with measurements obtained from surgical placement

Abstract

Bone dimensions' calculations are crucially important in the implant treatments for which different radiographic modalities such as panoramic and periapical techniques have been used. CBCT imaging systems gained more importance in the implant treatments and calculation of the bone dimensions recently due to their advantages. The present study compared the bone mesiodistal calculations accuracies using panoramic, CBCT and clinical methods as well as their diagnostic accuracy in the pre-implant assessments. Materials and Methods In this descriptive cross-sectional trial, panoramic and CBCT images were obtained from 100 patients referred for the implant treatments. Bone mesiodistal dimensions (distance between tooth's CEJ in the mesial of edentulous region to CEJ of the tooth in distal of edentulous region) were calculated using a scaled ruler in the panoramic images and the system software in the CBCT images. During implant insertions; the mucoperiosteal flap was raised and the clinical dimensions of the bone were measured by means of periodontal probe and bone gauge. The differences of the bone height and thickness measurements between gold standard and CBCT or panoramic modalities were statistically analyzed by means of Student t test. Results Mean ( standard deviation) of the bone height were 10.647 (1.55); 11.44 (1.51) and 10.685 (1.6) mm in the clinical, panoramic and CBCT modalities respectively. Significant differences were noted between the clinical and panoramic techniques (p<0.0001); however, no significant differences observed between the clinical and CBCT imaging when determining the bone height and thickness. During bone height calculations; 79%, 62% and 78% of the images ranked in the normal range using CBCT, panoramic and gold standard measurements respectively. The mean areas under the ROC curve were 0.92 and 0.83 in the CBCT and panoramic techniques. Conclusion The accuracy of CBCT images was higher than panoramic technique to measure the bone dimensions. Due to the insignificant differences between CBCT and gold standard measurements; the technique can be used with adequate confidence to calculate bone dimensions in the implant surgeries