Timing matters: dental development and outcomes on secondary alveolar bone grafting in cleft lip and palate patients

This is the first study to systematically evaluate the timing of secondary alveolar bone grafting (SABG) based on canine root mineralization stages (R-value), assessing its impact on bone graft preservation, canine eruption, and space closure in patients with cleft lip and palate (CLP).

This retrospective single-center cohort study included 104 patients with unilateral or bilateral CLP (127 cleft sites). Orthopantomograms and clinical records were evaluated at three stages: pre-SABG, six months post-SABG, and post-orthodontic treatment. The R-value was classified as R = 0,25 - 1,0, corresponding to 25-100% root development, respectively. Assessed parameters included the canine mineralization stage, axis-angulation and vitality, limbus height, probing depths, and space closure strategy. Group comparisons were performed using t-tests.

Early SABG (R ≤ 0,5) yielded significantly higher orthodontic space closure rates (71% versus 25% with late SABG, p < 0,05) with better graft preservation, but was associated with increased canine impaction (18,6% in lateral incisor agenesis cases). The mean axis-angle of cleft-side canines differed significantly between orthodontic and prosthodontic space closure (81,3° vs. 91,0°, t = 5,702). Limbus alveolaris height was reduced when SABG occurred after root completion (R = 1,0, t = 4,234). Periodontal probing depths remained < 3 mm, and canine vitality was preserved in all groups.

Early SABG, timed according to canine mineralization, supports alveolar bone preservation and space closure without compromising periodontal health.

Tailoring SABG timing based on dental development can optimize orthodontic and prosthodontic outcomes in patients with CLP.