Radiographic assessment of secondary autogenous alveolar bone grafting in cleft lip and palate patients

Objective: To assess if a 4-point, radiographically based scale could be used between operators to reliably assess the success of secondary alveolar bone grafting. Design: The study was retrospective with the clinicians blind to patient identity. Radiographs were examined twice by two clinicians with 1 week between assessments. Setting The research was carried out in a hospital-based orthodontic/oral and maxillofacial unit. Patients: All patients who had secondary alveolar bone grafting in this unit between February 1992 and March 1995 were included in this study, There were 38 patients with a total of 48 grafted sites. Interventions: The bone graft site was radiographed following orthodontic expansion prior to grafting. The radiograph was repeated postoperatively at a mean of 4 months after surgery, Main Outcome Measure: The degree of bony fill in the cleft area was assessed using a 4-point scale: Grade 1 >75% bony fill; Grade 2 50-75% bony fill; Grade 3 <50% bony fill; Grade 4 no complete bony bridge, Results: Overall, 50% of grafts achieved grade 1, 23% were grade 2, 22% grade 3, and 5% grade 4. Levels of intra- and inter-observer agreement were highly variable (.33 to .72 kappa statistic). Conclusions: The 4-point scale described could be used to assess the success of autogenous secondary alveolar bone grafting. It showed moderate to substantial intra-observer agreement, and fair-to-moderate inter-observer agreement.