A photogrammetric study of the effects of alveolar bone graft on nose symmetry among unilateral cleft patients

Abstract

Alveolar bone graft is considered conducive to tooth eruption and maxilla stability in unilateral cleft patients, but its contribution to nasal symmetry is still under discussion. To explore the detailed effects of alveolar bone graft on nasal symmetry and its role in rhinoplasty, 90 mixed-dentition complete unilateral cleft lip and palate patients were studied and categorised according to the operation they underwent during the mixed dentition period (bone graft, secondary rhinoplasty or bone graft and rhinoplasty combined). Standardised frontal and submental oblique photographs were taken before and after surgery, and objective measurements for the evaluation of nasal symmetry were devised. Measurement reliability was examined with the intraclass correlation coefficient. Intra- and inter-group comparisons were performed to explore the effect of bone graft on nasal symmetry and its role in rhinoplasty. The intraclass correlation coefficient values were >0.84. Preoperative inter-group analysis yielded satisfactory comparability. Among the bone-graft-only patients, seven of 10 measurements demonstrated significant differences, five indicated enhanced symmetry and two indicated compromised symmetry. For the rhinoplasty-only patients, all measurements revealed significant improvement. Compared with the patients who underwent rhinoplasty only, those who underwent combined bone graft and rhinoplasty were superior in nasal-base elevation only. The photogrammetric strategy appeared reliable for evaluation of nasal symmetry. Most of the effects imposed by alveolar bone graft on nasal symmetry were localised to the alar base and would be camouflaged by rhinoplasty. Considering the limited benefit in symmetry and the potential risk of more complications, overextended dissection during mixed dentition bone graft may be unnecessary.