Validation of a 3D methodology for the evaluation and follow-up of secondary alveolar bone grafting in unilateral cleft lip and palate patients.

Objective: The aim of the study was to propose and validate a method for three-dimensional (3D) quantitative assessment of secondary alveolar bone grafting (SABG) and its stability in time for patients with unilateral cleft lip and palate (UCLP).

Methods: Ten non-syndromic UCLP patients (9 males and 1 female with a mean age of 9.5 ± 0.9 years) undergoing SABG with good quality preoperative, immediate postoperative (6 weeks) and 6 months postoperative Cone Beam Computed Tomography (CBCT) scans were selected. Methods: The preoperative and 6 months postoperative scans were registered onto the immediate postoperative scan. The bone-grafted region was defined on the immediate postoperative scan and refined on the registered preoperative scan resulting in a 3D volume. The residual bone graft was calculated by applying threshold based segmentation on the registered 6 months postoperative scan within the segmented bone graft volume of the previous step. Inter and intra observer tests using intra-class correlation coefficient (ICC) were applied comparing the volumes of the 3D models.

Results: An excellent reliability was found for inter and intra observers with ICC ≥ 0.95.

Conclusions: The presented method proved to be reliable for volumetric assessment of the alveolar bone graft in UCLP patients, as well as to assess the percentage of bone resorption during follow-up.