Various methods of assessing the success of bone grafts have been proposed for the evaluation of secondary alveolar bone grafting in cleft patients. CBCT is more precise and reliable method compared to two dimensional radiographs to evaluate the size of the alveolar cleft defect, position and level of bone on adjacent teeth and presence of supernumerary teeth. Evaluation based on CBCT gives a better understanding of the defect for the surgeon and orthodontist which helps in treatment plan. Assessment of the bone fill should ideally be carried out at least 3 months after the bone grafting as grafted bone transforms into normal trabecular bone by 3 months. Resorption (height loss) of the bone graft occurs within 3 to 6 months after secondary alveolar bone grafting. The conclusions of the present study are: 1) 2D scales such as Enemark’s and Chelsea analysis and 3D scale proposed by A J Forte showed 80% of the patients had an acceptable outcome and 20% patients had an unacceptable outcome after secondary alveolar bone grafting. 2) On CBCT evaluation preoperative cleft volume was 0.88 ± 0.49 cm³ which was reduced to .2±.18 cm³ at 3 months and further reduced to .16±.18 cm³ at 6 months with percentage of bone fill 76.23% and 82.13 % at 3 months and 6 months respectively. There was an absolute difference of 28.71% of bone fill between 3 months and 6 months. 3) The average density of the unaffected side was 752.26± 66.11 HU and coincides with normal radiographic bone density of maxilla, where bone density D3 (350-850HU). Average density of bone graft was 375.38 ± 148.18 HU at 3 months which was reduced to 347.57 ± 137.10 HU at 6 months.