Dental arch dimensions in subjects with beta-thalassemia major

Thalassemia is a group of inherited hemoglobinopathies with thalassemia major representing the severe form of the disease characterized by craniofacial deformities. The aim of this study is to provide a detailed description of dental arch dimensions in subjects with thalassemia major.

The sample consisted of 43 thalassemic subjects, 24 males and 19 females, aged 7.3 to 15.4 years (mean ± SD = 10.6 ± 3.5 years) and control group matched by age and sex. Dental casts of the participants were measured for arch lengths, arch widths, using a digital sliding caliper. Student t-test was used for comparison of mean values between males and females as well as between thalassemic and control groups.

The results show that all means of maxillary and mandibular arch dimensions in thalassemic males and females were smaller than their controls, with 14 of the 16 comparisons being statistically significant (ranged from p < 0.05 to p < 0.001).The segmental arch lengths in the maxilla and mandible of thalassemic group were reduced by an average of 2.59 and 2.55 mm respectively, compared with the control group. The mean maxillary and mandibular arch depths (lengths) in the thalassemic group were shorter by 3.21 and 2.63 mm respectively, relative to the controls (p < 0.001). All arch widths thalassemic patients were significantly reduced by an average ranged from 1.33 to 1.90 mm in the maxilla and 1.37 to 1.77 mm in the mandible.

The present study showed that the maxillary and mandibular dental arches dimensions are significantly reduced in patients with thalassemia major compared with healthy control subjects.

Changes in the size of dental arches and tooth dimensions in thalassemic patients have an impact on the occlusal relationships.These changes should be taken into account when planning orthodontic treatment and orthognathic surgery.