Journal of Research in Dental
and Maxillofacial Sciences
Volume 11, Issue 3 (9-2026)
J Res Dent Maxillofac Sci 2026, 11(3): 185-194 |
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Abraham S, Raj P, Chitra P. Influence of Vertical Skeletal Pattern on Ramal Morphology and Optimal Screw Insertion Angulation. J Res Dent Maxillofac Sci 2026; 11 (3) :185-194
URL: http://jrdms.dentaliau.ac.ir/article-1-1427-en.html
URL: http://jrdms.dentaliau.ac.ir/article-1-1427-en.html
1- Department of Orthodontics and Dentofacial Orthopaedics, Army College of Dental Sciences, Secunderabad, Telangana, India, 500087.
2- Department of Orthodontics and Dentofacial Orthopaedics, Army College of Dental Sciences, Secunderabad, Telangana, India, 500087. ,prasadchitra@yahoo.co.uk
2- Department of Orthodontics and Dentofacial Orthopaedics, Army College of Dental Sciences, Secunderabad, Telangana, India, 500087. ,
Abstract: (6 Views)
Background and Aim: The mandibular ramus is increasingly used as an anchorage site for orthodontic miniscrews; however, anatomical variability related to vertical skeletal growth patterns may influence placement safety and stability. This study assessed mandibular ramus morphology, buccal cortical bone density, and insertion angles across different growth patterns using cone-beam computed tomography (CBCT), aiming to propose growth-pattern specific guidelines for ramal screw insertion.
Materials and Methods: This retrospective study analyzed CBCT scans of 81 adults aged 18-35 years. Subjects were equally stratified into hypodivergent, normodivergent, and hyperdivergent growth patterns. Standardized sagittal sections taken 5 mm above the occlusal plane were used to measure ramal width, thickness, height, proximity to the inferior alveolar nerve (IAN), cortical bone density, and ramal screw insertion angle. Intergroup comparisons were performed using one-way ANOVA with Tukey’s post-hoc test (alpha=0.05).
Results: Vertical growth pattern significantly influenced all parameters (P<0.001). Hypodivergent subjects showed the greatest ramal width, thickness, and height, IAN clearance, and the highest bone density. Hyperdivergent individuals demonstrated markedly reduced dimensions and the lowest density. The modified N-angle differed significantly, being smallest in hypodivergent (8.62 degrees) and greatest in normodivergent (27.45 degrees) types.
Conclusion: The results showed that vertical skeletal growth pattern significantly influences mandibular ramal morphology, cortical bone density, and screw insertion angulation. Hypodivergent individuals exhibited the most favorable anatomical characteristics, whereas hyperdivergent individuals demonstrated reduced dimensions and density, requiring steeper insertion angulations. These findings highlight the importance of growth pattern-specific planning to enhance the safety and predictability of ramal screw placement.
Materials and Methods: This retrospective study analyzed CBCT scans of 81 adults aged 18-35 years. Subjects were equally stratified into hypodivergent, normodivergent, and hyperdivergent growth patterns. Standardized sagittal sections taken 5 mm above the occlusal plane were used to measure ramal width, thickness, height, proximity to the inferior alveolar nerve (IAN), cortical bone density, and ramal screw insertion angle. Intergroup comparisons were performed using one-way ANOVA with Tukey’s post-hoc test (alpha=0.05).
Results: Vertical growth pattern significantly influenced all parameters (P<0.001). Hypodivergent subjects showed the greatest ramal width, thickness, and height, IAN clearance, and the highest bone density. Hyperdivergent individuals demonstrated markedly reduced dimensions and the lowest density. The modified N-angle differed significantly, being smallest in hypodivergent (8.62 degrees) and greatest in normodivergent (27.45 degrees) types.
Conclusion: The results showed that vertical skeletal growth pattern significantly influences mandibular ramal morphology, cortical bone density, and screw insertion angulation. Hypodivergent individuals exhibited the most favorable anatomical characteristics, whereas hyperdivergent individuals demonstrated reduced dimensions and density, requiring steeper insertion angulations. These findings highlight the importance of growth pattern-specific planning to enhance the safety and predictability of ramal screw placement.
Type of Study: Original article |
Subject:
orthodontic
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