Symphysis morphology and mandibular alveolar bone thickness in patients with β-thalassemia major and different growth patterns

Abstract

Objective: The present study aimed to assess the morphology of symphysis and alveolar bone thickness (ABT) surrounding mandibular incisors in thalassemic patients, as compared to unaffected individuals. Methods: This case-control study was conducted on lateral cephalograms of 60 thalassemic and 60 unaffected patients with Class II malocclusion seeking orthodontic treatment at Dental School, Shiraz University of Medical Sciences. The sample was divided into three subgroups including hyperdivergent, normodivergent, and hypodivergent, according to the Jarabak index. Symphysis dimensions and alveolar bone thickness surrounding mandibular incisors were measured using AutoCad software. Finally, the correlation between alveolar bone thickness and symphysis morphology was assessed. Results: In general, chin dimensions and bone thickness at different levels of mandibular incisor roots (cervical, middle, apical) were smaller in thalassemic adolescents than controls. Concerning the total sample as well as the normodivergent subgroup, significantly lower values were observed in thalassemic patients for symphysis width, total ABT at the cervical, and lingual ABT at the apical root area compared to controls (p < 0.05). The hypodivergent growth pattern was not associated with any statistical differences between the groups (p> 0.05). In both thalassemic and control subjects, symphysis width showed a weak to moderate positive correlation with ABT of lower incisors (p< 0.05), whereas symphysis height showed a moderate positive correlation with cervical ABT in only ß‐thalassemia patients (p< 0.05). Conclusions: Compared to controls, ß-thalassemia patients showed thinner alveolar bone at different levels of lower incisor roots and smaller symphysis dimensions. There were significant correlations between symphysis dimensions and alveolar bone thickness of mandibular incisors in the sample.

Success rates of single-thread and double-thread orthodontic miniscrews in the maxillary arch

“…Among various types of TADs, miniscrews are the most widely used in clinical practice due to their small size, ease of insertion and removal, and cost-effectiveness compared to other systems [ 4 , 5 ]. Miniscrews enable efficient and versatile tooth movements such as intrusion or retraction of anterior and posterior teeth, correction of canted occlusal plane, unilateral space closure, and alignment of dental midlines [ 6 – 9 ].…”

Mandibular Canal Branching Assessed With Cone-Beam Computed Tomography

“…The high accuracy of threedimensional imaging enables the clinician to observe the fine anatomy of the craniofacial skeleton, including the location and direction of neurovascular bundle branches. 2,[9][10][11][12][13] Various classifications of mandibular canal branching have been proposed in the literature according to the location and configuration of the accessory mandibular canal and the diagnostic tool applied. 6,[14][15][16] Carter and Keen 14 pioneered in evaluating the intramandibular course of IAN based on cadaveric dissection.…”

“…After the introduction of cone-beam computed tomography (CBCT) into dental practice, it rapidly became a golden standard for the diagnosis of anatomical structures. The high accuracy of three-dimensional imaging enables the clinician to observe the fine anatomy of the craniofacial skeleton, including the location and direction of neurovascular bundle branches 2,9–13 …”