Outcome following secondary autogenous bone grafting before and after canine eruption in patients with unilateral cleft lip and palate.

Objective: To determine whether the long axis and eruption of the cleft-adjacent canine affect postoperative outcomes in secondary autogenous bone grafting (SABG).

Methods: Retrospective longitudinal study. Methods: Multidisciplinary long-term follow-up at Kagoshima University Hospital. Methods: Twenty-five patients with complete unilateral cleft lip and palate (11 male, 14 female) were compared between unerupted and erupted groups for canine developmental stage, canine angle, and vertical height at bone grafting at 1 year and more than 4 years after SABG. The interalveolar septal heights at 1 and more than 4 years were evaluated by orthopantomograms.

Results: All patients in both groups accomplished dental rehabilitation with orthodontic treatment alone without prosthetic appliances. Although the rate of an acceptable bone bridge tended to be lower in the unerupted group (62.5%) than in the erupted group (88.8%), the difference was not significant (P = .158). The canine angle at bone grafting was significantly different between acceptable (69.2° ± 12.2°) and poor cases (77.3° ± 6.2°) at more than 4 years in the unerupted group (P = .049). The acceptable bone bridge rate might reflect mechanical stress added by natural eruption and orthodontic force.

Conclusions: We suggest that SABG should be planned in accordance with the canine angle, crown and root development, the eruption position of the cleft-adjacent canine, and the timing of added mechanical stress in the alveolar cleft, considering the bone formation in the alveolar cleft.