Orthognathic surgery need following BAMP therapy in unilateral complete cleft lip and palate with moderate to severe maxillary deficiency: a prospective study.

BACKGROUND

The objective of this study was to assess the long-term stability of bone-anchored maxillary protraction (BAMP) in patients with unilateral complete cleft lip and palate (UCLP) and sagittal midface deficiency.

METHODS

The sample comprised 30 patients with UCLP (20 males and 10 females), with a mean age of 11.8 years (standard deviation = 0.79 years). All patients presented with moderate to severe maxillary deficiencies and were prospectively treated with BAMP for 18 months. Cone-beam computed tomography was obtained before (T1) and after BAMP therapy (T2), whereas conventional lateral cephalograms were acquired at least 5 years after BAMP therapy (T3: mean age = 20.15 years, standard deviation = 2.38 years). Moreover, 3 patients were lost during the follow-up, and 1 was excluded because of missing T2 records. Interphase comparisons were performed using analysis of variance and Tukey honest significant difference test (P <0.05). Discriminant analysis was used to identify pre and posttreatment predictive variables associated with surgical or nonsurgical outcomes.

RESULTS

Among the 26 patients included in the final sample, 46.2% (n = 12) received nonsurgical treatment in phase 2, whereas 53.8% (n = 14) required orthognathic surgery. In the nonsurgical subgroup, the outcomes achieved with BAMP therapy remained stable from T2 to T3. In the surgical subgroup, treatment changes were negligible, and an impairment of facial convexity was observed during the posttreatment follow-up. Discriminant analysis revealed that pretreatment indicators predictive of nonsurgical outcomes included a less negative overjet, a smaller mandibular plane angle, and a reduced gonial angle. Greater improvements in the ANB angle and overjet during treatment were associated with a higher likelihood of a nonsurgical outcome.

CONCLUSIONS

Patients with UCLP who achieved a positive overjet during BAMP therapy remained stable in the long-term, and orthognathic surgery was avoided. Hyperdivergent growth pattern with obtuse gonial angle and more severe negative overjet were initial predictors of the need for orthognathic surgery. Greater correction of the skeletal maxillomandibular relationship and overjet during BAMP therapy was associated with nonsurgical outcomes.