A comparative study of two CBCT images on assessing the amount of bone in the maxillary posterior region

Objective:To evaluate the accuracy of the measurement of the sinus ridge distance and the proximal and distal middle distance in the maxillary posterior missing tooth area by oral and maxillofacial conebeamCT(CBCT) panoramic view and cross section view. Methods:60 patients in CBCT database were selected to measure the available bone height (sinus ridge distance) and available bone width ( the proximal and distal middle distance) of the missing tooth area of the second premolars, the first molars and the second molars in panoramic view and cross-section view respectively, and the measurement results of different tooth positions were statistically analyzed. Results:there was significant difference in bone width (near and far middle distance) between CBCT panoramic view and cross section view, and the measured value of cross section view was smaller than that of panoramic view, but there was no significant difference in the available bone height (sinus ridge distance) and the measured values between different observers (P>0.05).There were also statistical differences among the measured values of different tooth positions (P<0.05), among which the proximal and distal middle distance of the first premolars was the smallest, the sinus ridge distance was the largest, and the sinus ridge distance of the second molars was the smallest. Conclusion:CBCT can assist in the measurement of bone mass in the area of absence of tooth,which is of great significance to the development of the treatment plan of the oral cavity.