Radiographic examinations to determine changes in bone mass in maxillary sinus floor augmentation have been conducted primarily using panoramic radiography [8–12], which allows for the assessment of the height of the maxillary sinus in only two dimensions. In addition, it does not allow for detailed examination or measurement of the interior of the maxillary sinus without factoring in magnification or distortion. Hounsfield developed X-ray computed tomography in 1982. In 2001, cone-beam computed tomography (CBCT), the features of which included low exposure and high spatial resolution, became available in the clinical setting. Shortcomings of CBCT are that it delivers inferior spatial resolution of soft tissue compared with conventional CT and does not offer the quantification of CT values. However, narrowing the field of view (FOV) decreases the amount of radiation exposure. Moreover, its greatest advantages include isotropic spatial resolution (voxel) and high spatial resolution (superior resolution of bone), which allow for the accurate measurement of the interior of the maxillary sinus.

The purpose of this study was to examine the effect of bone grafting material resorption on volumetric change and the predictability of the long-term progress of sinus floor augmentation using β-TCP by performing radiographic examinations using CBCT.