A Comparative Study of the Accuracy and Reliability of Multidetector Computed Tomography and Cone Beam Computed Tomography in the Assessment of Dental Implant Site Dimensions

MastersObjectives: The goal of implant site imaging is to acquire accurate and reliable measurements of the proposed implant sites which aid in the determination of optimum implant location, size, and angulation. The aim of this study, therefore, was to investigate the accuracy and reliability of linear measurements of edentulous ridges recorded from both MDCT images and CBCT images acquired using a flat panel detector (FPD) with a large field of view (FOV), both independently and in comparison to each other. Material and Methods: Four maxillae and five mandibles from human dry skulls were used in the study. The edentulous areas to be measured were marked with radiopaque gutta percha markers in order to standardize the plane of the transverse cross-sections as well as the path of measurements. The skulls were imaged in a 16-row spiral CT scanner as well as in a CBCT device with a large FOV and a FPD. The ridge dimensions were recorded from reformatted transverse cross-sectional images by two observers. These measurements were compared to caliper measurements recorded directly from the bone. Thirtyeight height and 42 width measurements were included in the study. The measurement errors were calculated for each modality and compared to each other. The intra- and inter-examiner reliability of the results were evaluated, as well as the statistical significance of findings. Results: The intra-examiner reliability score of the direct bone measurements was found to be 0.999. While the MDCT intra- and inter-examiner reliability scores were 0.994 and 0.985 respectively, those for CBCT were 0.995 and 0.958 respectively. The overall mean of the absolute MDCT errors was 0.75 mm with a standard deviation of 1.09 mm. On the other hand, that of the CBCT absolute errors was 0.49 mm with a standard deviation of 0.47 mm. The mean of the MDCT absolute errors was significantly larger than that of the CBCT absolute errors. Conclusions: The measurements recorded from both MDCT and CBCT images had a high inter- and intra-examiner reliability, but were both associated with a clinically and statistically significant measurement error. The higher image resolution of CBCT images led to smaller measurement errors, compared to MDCT