Accuracy of magnetic resonance imaging compared with computed tomography for implant planning

Aim: The objective of this study was to evaluate the reliability of magnetic resonance imaging (MRI) compared with computed tomography (CT) for dental implant planning in respect to bone measurements. Methods: Five dry mandibles were submitted to MRI and CT examinations. Each mandible had three specific sites identified with markers, in a total of 15 sites to be studied. The images provided by the MRI and CT examinations were delivered to four specialists in Oral and Maxillofacial Radiology to measure the bone height at the specific sites. Subsequently, the bone height of the dry mandibles was directly measured in the determined sites. The measurements obtained by the specialists in MRI and CT images were compared with the measurements obtained directly from the dry mandibles using the ANOVA test with a 0.05 significance level. Results: The differences between the measurements obtained directly from the dry mandibles and the measurements from the MRI exams varied from 0.13 to 1.67 mm, with 10 sites being overestimated in MRI exams and five sites being underestimated. The differences between the measurements from the dry mandibles and CT exams varied from 0.02 to 1.25 mm, with nine sites being overestimated in CT exams and six sites being underestimated. The differences between the measurements from the MRI and CT exams varied from 0.03 to 1.00 mm, with nine sites giving higher values in MRI exams and six sites giving higher values in CT exams. There were no statistically significant differences between the three grous of measurements (P=0.98). Conclusion: The MRI, when compared with CT, shown to be reliable in respect to bone measurements for dental implant planning.