Objective. Secondary alveolar bone grafting (SABG) has become the principal means of treating alveolar cleft defects. We reviewed the literature on 2-dimensional (2-D) and 3-dimensional (3-D) radiographic evaluation of SABG in patients with cleft lip and alveolus (CLA) and those with cleft lip and palate (CLP), with a focus on outcomes. Study Design. We searched several electronic databases to the end of 2018. The inclusion criteria were nonsyndromic CLA or CLP treated with SABG at an optimal age and evaluation performed no earlier than 3 months postoperatively. Study quality was evaluated by using the Methodological Index for Non-Randomized Studies and the Cochrane Collaboration tool. Results. We identified 282 articles from 3 databases. Full texts of 102 articles were analyzed, and finally 11 articles were included for qualitative analysis. 2-D and 3-D radiographic evaluations were performed in each study. Traditional 2-D radiographic imaging tended to overestimate success; bone resorption in the labiopalatal direction was inaccurate in 2-D views. Most articles were observational in nature and of moderate methodologic quality. Conclusions. 2-D evaluation tended to overestimate SABG outcomes; 3-D evaluation was more precise and reliable than 2-D radiography. A gold standard 3-D evaluation protocol is required for quantitative comparisons in the future. (Oral Surg Oral Med Oral Pathol Oral Radiol 2020;130:455À463)

Background Secondary alveolar bone grafting (SABG) is an integral part of the treatment for cleft lip and alveolus and cleft lip and palate. However, the outcome of SABG was not satisfactory as expected, factors that affecting the outcome were still controversial. The aims of this study were to summarize a new method for the classification of alveolar cleft morphology in patients with unilateral cleft lip and alveolus or unilateral cleft lip and palate, to evaluate the correlation between the morphology and SABG outcomes, to identify factors that might predict the outcomes. Methods The characteristics of the cleft morphologies of 120 patients who underwent SABG were observed using the preoperative Cone-Beam Computed Tomography (CBCT) images. 52 patients who had CBCT scans performed at least 6 months after SABG were included for the evaluation of outcomes. Both categorical and continuous evaluation methods were measured. Correlations between cleft morphology and SABG outcomes were assessed using the Pearson correlation coefficient in SPSS 27.0.0. Results A new method for the classification of cleft morphology was summarized:type I, prism type (labial defect size ≥ palatal defect size; nasal defect size ≥ occlusal defect size); type II, prism’ type (labial defect ≥ palatal defect; nasal defect < occlusal defect); type III, inverted prism type (palatal defect ≥ labial defect); type IV, funnel type (presented as a significantly narrow defect area in the middle towards the vertical dimension); and type V, undefinable (extremely irregular morphology can’t be defined as any of the above types). Categorical evaluation showed 8 failure, 11 poor, 12 moderate, and 21 good results, while the average bone filling rate was 59.24 ± 30.68%. There was a significant correlation between the cleft morphology and categorical/continuous evaluation outcome (p < 0.05). Conclusion The new method for the classification of alveolar cleft morphology summarized in this study was comprehensive and convenient for clinical application. Both categorical and continuous methods should be used for radiographic assessments in patients undergoing SABG. The chances of a successful procedure might be better when the patient has type I or IV morphology, in which the shape is like a funnel in the relatively palatal or occlusal area towards the vertical dimension. A relatively great amount of bone resorption was observed in most patients. Trial registration Chinese clinical trial registry; registration number: ChiCTR2100054438.