Effect of cuspid positioning in the cleft at the time of secondary alveolar bone grafting on eventual graft success.

This investigation was to determine the relationship between the success of secondary alveolar bone grafting and the position of the permanent cuspid relative to the cleft at the time of grafting. In this retrospective study utilizing periapical radiographs take on cleft patients to evaluate bone grafting results, the subjects were patients treated at the Lancaster Cleft Palate Clinic, a private institution specializing in the care of cleft patients. Sixty-seven patients (20 BCLP; 47 UCLP) were selected for this study based on availability of quality radiographs and a minimum of 6-month post-surgical follow-up. All patients underwent alveolar bone grafting (mean age, 10 years 7 months). Presurgical radiographs were taken within 3 months of the operation. Post-surgical radiographs were taken to evaluate the outcome of grafting (mean follow-up, 2 years 10 months). Radiographs were traced and digitized on a total of 86 cleft sites. Presurgically, a ratio was used to determine the amount of cuspid crown emerged through the alveolus into the cleft site relative to the anatomic cuspid-crown length. Post-surgically, ratios of bone support for the teeth mesial and distal to the cleft were established by dividing the amount of root covered by bone by the anatomic root length. Ratios expressing the height of alveolar crest relative to the cementoenamel junction (CEJ) of adjacent teeth and amount of alveolar notching relative to the mesial tooth root length were also evaluated. Linear regressions of each of the five ratios of graft outcome on the cuspid-eruption ratio were done. No significant correlations could be found between final graft success and the amount of cuspid crown exposed in the cleft at the time of grafting. Cuspid position could not be shown to be a significant factor in determining graft success.