Objective : To determine the accuracy of volumetric measurement of a simulated alveolar bone defect using cone-beam computed tomography (CBCT) scans. Design : Laboratory-based observational study. Setting : University dental teaching hospital. Methods : Scans of a dried skull with an artificially created maxillary bone defect. Main Outcome Measures : The skull was scanned using an i-CAT CBCT scanner (Imaging Sciences International, Hatfield, PA) at 0.2 mm resolution. The superior and inferior aspects of the void were identified, and the volume was calculated by three-dimensional (3D) computational analysis of the CBCT scan using an algorithm created with MATLAB software (The Mathworks Inc., R2009a, Natick, MA). The skull was then scanned using micro computed tomography (micro-CT) at 0.0934 mm resolution, and the volume of the defect was determined using the Studio Max 2.2 program (Volume Graphics, 2012, Heidelberg, Germany). The process was repeated two additional times, and the volumes were compared using a two-sample t test (P < .05). To determine the interobserver reproducibility of the identification of the superior and inferior aspects of the defect, the slices chosen to represent these extremities were selected by four separate observers and the data assessed using an F-test (P < .05). Results : The interobserver reproducibility of the identification of the superior and inferior boundaries of the defect was good (P = .18). The volumes computed from the i-CAT CBCT images were 4.11% lower than those computed from the micro-CT images; however, the difference was not statistically significant (P = .71). Conclusions : 3D volumetric measurement of simulated alveolar bone defects using i-CAT CBCT scans is similar to the volumes determined using micro-CT.

Accuracy of both virtual and printed 3-dimensional models for volumetric measurement of alveolar clefts prior to alveolar bone grafting compared to a validated algorithm Kasaven, C. P.; McIntyre, Grant; Mossey, Peter General rightsCopyright and moral rights for the publications made accessible in Discovery Research Portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from Discovery Research Portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain.• You may freely distribute the URL identifying the publication in the public portal. Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Results: Inter-observer reliability was almost perfect (ICC = 0.987). There were no significant differences between the three methods (p>0.05) although virtual 3D models were the most precise with the smallest standard deviations and confidence intervals.Conclusion: In this preliminary investigation, virtual 3D and 3D printed models were as precise as the validated computer algorithm for calculating alveolar cleft volumes prior to bone grafting but virtual 3D models were the most accurate and subject to further investigation could be a useful adjunct in clinical practice.