Accuracy of graft volume assessment for sinus lift surgeries using automatically driven virtual patient

Even though bone graft insertion for sinus lift procedures has been performed since 1980, graft volume assessment is not always approximated according to objective presurgical planning techniques. As a result, the volume is frequently excessive or insufficient. The aim of this study was to propose a methodology for graft volume assessment based on an automatically driven virtual patient and compare it to the actual intraoperative volume for cases assigned for lateral sinus floor elevation to assess its accuracy. Thirty-six pre-operative CBCT scans acquired for presurgical planning of lateral window sinus lift were used. First, the DICOM files were uploaded to the virtual patient creator platform (Relu BV, Belgium) to obtain automated segmentation of the maxillary sinus and related teeth in STL format. Based on consultation with the oral surgeon to determine the number and dimensions of implant(s) required, a height equivalent to the planned implant was measured from the alveolar bone crest at the center of the augmented region. Finally, the corresponding volume was extracted in 3-matic (Materialise N.V., Leuven, Belgium) using the trim tool. The actual intraoperative volume was measured with a 5-mL sterilized syringe. Mean estimated volume was 1.45 and mean actual volume was 1.43, with no significance between them. Th correlation coefficient between the two volumes was 0.88, indicating a strong correlation. Use of automated virtual patient could provide fast, accurate, and consistent 3D virtual models that can improve the quality and predictability of presurgical planning. The proposed methodology allowed for a reliable simulation of the actual graft volume.