Comparative Effect of Conventional and 3D-printed Twin Block Appliances on Soft Tissue Changes

Background: Enhancing facial aesthetics is the main target of orthodontic treatment, as appearance greatly influences a person's social confidence and self-esteem. Skeletal Class II malocclusion is quite common, and the pubertal growth spurt is the perfect time for functional treatment to promote mandibular advancement. The Twin-Block, one of the most widely used functional appliances, is a popular choice for achieving this goal..

Patients and methods: Twenty patients divided into two groups with mixed or early permanent dentition were enrolled. Lateral cephalometric radiographs were taken at the start (T0; before treatment) and end (T1; at the end of the active phase) using the same machine. Those of each patient treated with a conventional Twin Block appliance for class II malocclusion were compared to those of patients treated with a 3D-printed Twin Block appliance for a 6-month follow-up period. Both groups were evaluated for soft tissue changes using various angular and linear geometric measurements, and differences between pre- and post-treatment were analyzed with a paired t-test.

Inclusion criteria

1- Young, growing age from 9 to 16 years. 2. Class II malocclusion with retruded mandible. 3. Increased overjet.

Exclusion criteria

• Severe proclination of anterior teeth. 2. Severe crowding of anterior teeth. 3. Systemic disease affecting bone and general growth.

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