Long-Term Effect of Maxillary Distraction Osteogenesis (DO) on Nasal Index in Adult Patients with Cleft Lip and Palate Deformities

Purpose

To test the hypothesis that there is no immediate and long-term effects of maxillary distraction osteogenesis (DO) on nasal index among adult subjects with cleft lip and palate deformities.

Materials and Methods

Twelve adult subjects in the age range of 17–20 years with complete unilateral cleft lip and palate underwent advancement of maxilla by DO. The immediate and long-term effects of maxillary DO on nasal index were evaluated from extra-oral full face frontal photographs recorded prior to DO (T₀), at the end of active DO (T₁) and at least 2-years after the DO (T₂). The ANOVA, Post Hoc test (Bonferroni) and Pearson correlation coefficients were used. The probability value (P value) 0.05 was considered as statistically significant.

Results

SNM angle and Ptm-M distance increased significantly by DO (P < 0.001). The nasal index increased significantly (P < 0.01) by 13.85 % from T₀ value of 85.15 ± 4.49 to 99.02 ± 11.16 % at the end of active distraction (T₁) and by 12.69 to 97.84 ± 9.14 % at the end of long-term follow-up (T₂). The correlation between sagittal maxillary advancement and nasal index was statistically significant (P < 0.001). For each millimeter of maxillary advancement, the nasal index increased by 1.38 % and 1.8 % at the end of active distraction and long-term follow-up respectively.

Conclusion

The advancement of maxilla by distraction osteogenesis among subjects with cleft lip and palate deformities increased nasal index significantly.