Soft-tissue profile characteristics in children with beta thalassaemia major

Abstract

Objectives: To compare soft-tissue profile characteristics of patients with beta thalassaemia major (BTM) with a group of non-thalasseamic subjects with a similar skeletal pattern. Subjects and methods. The material for this cross-sectional retrospective study consisted of lateral cephalograms of 40 BTM patients (23 males, 17 females, aged 9.5 ± 0.97 years). These were compared with lateral cephalograms of a control group of 40 non-thalasseamic subjects (23 males, 17 females, aged 11.0 ± 0.87 years) who had similarities with the study group in the following cephalometric variables: SNA (°), SNB (°), ANB (°) and anterior face height (N-Me). Overall, 22 linear and angular soft-tissue cephalometric variables were measured. Results. Horizontal soft-tissue measurements, except for the thickness at B point (B-B'), were larger relative to non-thalasseamic subjects; particularly showing a statistically larger mean values for the following variables: soft-tissue thickness at Pronasale (ANS-Prn, p < 0.01), Subnasale (ANS-Sn, p < 0.01), point A (A-A′, p < 0.01) and at the Pogonion point (Pg-Pg′, p < 0.05). Compared to controls, BTM patients showed significantly larger (p < 0.05) mean values for the anterior nose length (Prn-Prn', p < 0.01) and lower nose height (Prn-Sn, p < 0.05). Variables that represented the lip profile, including the nasolabial angle, did not significantly differ from controls. The average values for the mid-face (N-ANS), posterior face height (S-Go) and the inclination of maxillary incisors to the SN plane were significantly larger (p < 0.01) in BTM patients. Conclusion: The soft-tissue profile differences in BTM patients may have implications for their future orthodontic or orthognathic management. Future studies can investigate the 3D soft-tissue changes and the possible contributing factors.