Craniofacial Deformities in Patients With Beta-Thalassemia: Orthodontic Versus Surgical Correction-A Systematic Review

Evaluation of craniofacial anthropometry of children with β-thalassemia major in the eastern Anatolia: a case-control study

OBJECTIVE

The present study aims to compare β-thalassemia major patients and healthy individuals in terms of anthropometric characteristics and changes in craniofacial profile.

SUBJECTS AND METHOD

Craniofacial anthropometric measurements were performed on a total of 422 subjects (199 β-thalassemia major patients and 223 healthy individuals) by using a millimetric caliper and tape measure on 19 anthropometric parameters (8 horizontal, 10 vertical, and 1 head circumference) in cranial, facial, nasal, orolabial, and orbital zones.

RESULTS

The difference between the orbital, nasal, and orolabial zone parameters of healthy subjects and β-thalassemia major patients was found to be statistically significant (p < 0.05). There was no statistically significant difference between the groups in terms of head circumference in the cranial zone and total facial height in facial zone (n-gn) values (p˃0.05). In intragroup comparison between females and males with β-thalassemia, statistically significant differences were found in forehead width (ft-ft), forehead height (tr-gl), right eye width (R ex-ex), and upper lip height (sn-stm) (p < 0.05).

CONCLUSION

Understanding the craniofacial profile changes in β-thalassemia major patients and increasing our knowledge about the relationship between the course and severity of disease and the level of these changes would contribute to the advancements in diagnoses to be made in facial and jaw zones of these patients and in the treatment plans.

CLINICAL RELEVANCE

We believe that the analysis and results of the craniofacial anthropometric data obtained in the study will contribute to the diagnosis and treatment processes of patients with β-thalassemia major in areas of expertise such as craniofacial surgery, orthodontics, and hemato-oncology.

Evaluation of Quantitative Aspects of Craniofacial Deformities in Transfusion Dependent Beta-Thalassemia Major Patients: A Cephalometric Study

PURPOSE

To evaluate the quantitative (cephalometric) aspects of the craniofacial deformities in transfusion-dependent beta-thalassemia (TDT) patients.

MATERIALS AND METHODS

Sixty-five TDT patients receiving a regular blood transfusion in the Department of Pediatrics of age group 5 to 8 years (younger) and 15 years and above (older) were compared with control groups of similar age using cephalograms (lateral and posterior-anterior view).

RESULTS AND OBSERVATION

The prevalence of skeletal class II tendency is higher in thalassemic patients that do not improve with age. The thalassemic patients were found to show large angle ANB i.e.. Angle between points point a, nasion and point B (ANB), large flexure angle, small angle SNB i.e.. Angle between points sella, nasion and point B (SNB), and normal angle SNA i.e.. Angle between points sella, nasion and point A (SNA) angles suggestive of retrognathic mandible. The thalassemic patients were observed to have smaller transverse widths and thickened calvarium on the posterior-anterior view.

CONCLUSION

The skeletal class II malocclusion appears to be a manifestation of generalized growth retardation/delayed puberty in thalassemic patients leading to diminished mandibular growth, rather than maxillary prognathism due to marrow hyperplasia.

Craniofacial shape in patients with beta thalassaemia: a geometric morphometric analysis

The shape of the craniofacial complex of patients with beta thalassaemia was evaluated using geometric morphometrics on lateral cephalometric radiographs and was compared with matched controls. The beta thalassaemia group consisted of 40 patients (16 females, 24 males, mean age 33.4). Each patient was matched by age and gender to two controls (32 females, 48 males, mean age 33.1). The 120 lateral cephalometric radiographs were digitized and traced with 15 curves, 10 landmarks and 117 sliding semi-landmarks. These landmarks were subjected to Procrustes superimposition and principal component analysis in order to describe shape variability of the cranial base, maxilla and mandible, as well as of the entire craniofacial complex for each sex. The first 4 principal components accounted for 50% of the total sample's variability. The beta thalassaemia group was significantly different in overall shape to the control group for both sexes. Similar findings were noted for the maxilla, the mandible and the cranial base. The main differences were related to smaller mandibular body for the thalassaemia group, midface protrusion and decrease in posterior face height. The shape of the craniofacial complex in these patients is prone to be more convex and hyperdivergent.

Assessment of mandibular characteristics in patients affected with β-thalassaemia major: A retrospective case-control study

OBJECTIVE

Thalassemia is the most common hereditary blood disorder across the world. This study aimed to identify some mandibular features of thalassaemic patients and compare them with unaffected counterparts.

MATERIAL AND METHODS

This retrospective case-control study was carried out on lateral cephalograms of 60 subjects (26 males, 34 females) with class II malocclusion and age range of 11 to 15 years. The control group consisted of 60 non-thalassaemic subjects with class II malocclusion and similar chronological age, gender and vertical facial dimension. Based on the Jarabak index, the case and control subjects were classified into hyperdivergent, normodivergent and hypodivergent growth patterns. Four linear (ramus height, ramus width, mandibular depth, and antegonial notch depth) and 3 angular (symphyseal angle, gonial angle, and mandibular arc angle) cephalometric parameters were measured to represent mandibular morphology. The data were analysed using Chi-square test and Student's t-test.

RESULTS

No significant difference was found in linear measurements between thalassaemic patients and controls. The symphysis angle was significantly greater and the mandibular arc angle was significantly smaller in the total thalassaemic sample than the control individuals (P<0.001 and P=0.004, respectively). The difference in symphysis angle was significant in both hyperdivergent and normodivergent subjects (P=0.004 and P=0.002, respectively), whereas the difference in mandibular arc angle was only significant in the normodivergent subgroup P=0.001).

CONCLUSIONS

The smaller mandibular arc angle in the thalassaemic sample suggests a more superior than posterior growth direction of condyles compared with healthy individuals. The difference in symphyseal angle represents inherent differences in chin morphology between thalassaemic subjects and controls.