Accuracy of both virtual and printed 3-dimensional models for volumetric measurement of alveolar clefts before grafting with alveolar bone compared with a validated algorithm: a preliminary investigation.
Our objective was to assess the accuracy of virtual and printed 3-dimensional models derived from cone-beam computed tomographic (CT) scans to measure the volume of alveolar clefts before bone grafting. Fifteen subjects with unilateral cleft lip and palate had i-CAT cone-beam CT scans recorded at 0.2mm voxel and sectioned transversely into slices 0.2mm thick using i-CAT Vision. Volumes of alveolar clefts were calculated using first a validated algorithm; secondly, commercially-available virtual 3-dimensional model software; and finally 3-dimensional printed models, which were scanned with microCT and analysed using 3-dimensional software. For inter-observer reliability, a two-way mixed model intraclass correlation coefficient (ICC) was used to evaluate the reproducibility of identification of the cranial and caudal limits of the clefts among three observers. We used a Friedman test to assess the significance of differences among the methods, and probabilities of less than 0.05 were accepted as significant. Inter-observer reliability was almost perfect (ICC=0.987). There were no significant differences among the three methods. Virtual and printed 3-dimensional models were as precise as the validated computer algorithm in the calculation of volumes of the alveolar cleft before bone grafting, but virtual 3-dimensional models were the most accurate with the smallest 95% CI and, subject to further investigation, could be a useful adjunct in clinical practice.
University of Dundee Dental Hospital, 2 Park Place, Dundee DD1 4HR, UK.
C P
CP
Kasaven
University of Dundee Dental Hospital, 2 Park Place, Dundee DD1 4HR, UK. Electronic address: grant.mcintyre@nhs.net.
G T
GT
McIntyre
University of Dundee Dental Hospital, 2 Park Place, Dundee DD1 4HR, UK.
P A
PA
Mossey
D000465:Algorithms; D064728:Alveolar Bone Grafting / Q000379:methods*; D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery*; D002971:Cleft Lip / Q000000981:diagnostic imaging / Q000601:surgery; D002972:Cleft Palate / Q000000981:diagnostic imaging / Q000601:surgery; D017076:Computer-Aided Design; D054893:Cone-Beam Computed Tomography; D006801:Humans; D066330:Printing, Three-Dimensional; D015203:Reproducibility of Results; D014584:User-Computer Interface
3D; CAD-CAM models; bone grafting; micro-CT; volumetric assessment