Volumetry of simulated bone grafts in the edentulous maxilla by computed tomography: an experimental study.
OBJECTIVE
To determine the precision of CT for calculating the volume of bone grafts to the maxilla.


METHODS
Plaster of Paris was used to simulate bone as onlay and inlay grafts to the maxillary alveolus and sinus in a dry skull. Two mm thick axial CT scans were obtained. The area of the graft on each slice was measured and volumes calculated according to the formula V(graft)=Sigma of areas x the thickness of each section. Scans were repeated with the skull at approximately +5 degrees and -5 degrees to the horizontal plane and the calculations repeated. The real volume was calculated by the displaced water technique. Precision was estimated as reliability coefficient.


RESULTS
The reliability coefficients for the right and left inlay and the onlay grafts were 0.97, 0.6 and 0.96 respectively.


CONCLUSIONS
Calculations of the volume of both inlay and onlay grafts to the maxilla from axial CT is precise.
Johansson
B
B
Department of Surgical Sciences, Oral and Maxillofacial Surgery, Uppsala University Hospital, S 751 85 Uppsala, Sweden.
Grepe
A
A
Wannfors
K
K
Aberg
P
P
Hirsch
J M
JM
D000465:Algorithms; D000540:Alveolar Ridge Augmentation / Q000379:methods; D001699:Biometry; D016025:Bone Transplantation / Q000000981:diagnostic imaging* / Q000473:pathology; D002133:Calcium Sulfate / Q000737:chemistry; D002138:Calibration; D003764:Dental Materials / Q000737:chemistry; D006801:Humans; D007575:Jaw, Edentulous / Q000000981:diagnostic imaging / Q000601:surgery*; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery*; D008443:Maxillary Sinus / Q000000981:diagnostic imaging / Q000601:surgery; D008953:Models, Anatomic; D011856:Radiographic Image Enhancement; D015203:Reproducibility of Results; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed
D003764:Dental Materials; D002133:Calcium Sulfate