Differentiated Selection of Retention After Mandibular Incisor Alignment With Regard to the Skeletal Growth Pattern and Alveolar Bone Density

Objective. To assess the relationship between the skeletal growth pattern, optical density of the anterior mandibular alveolar bone, and the risk of relapse after orthodontic treatment. Materials and methods. A total of 158 adolescents aged 13–17 years were examined: 69 with a vertical hyperdivergent, 53 with a horizontal hypodivergent growth pattern, and 36 controls. Clinical, cephalometric, and CBCT densitometric methods were used; 122 patients were followed for 12 months of retention. Results. Mean optical density was 379 HU in the hyperdivergent, 749.5 HU in the hypodivergent, and 549.5 HU in the normodivergent groups. Relapse or complications occurred in 11 patients (9%), all associated with fixed retainers. Conclusions. The growth pattern and the condition of the osseous envelope should be considered when determining the final mandibular incisor position and selecting retention.