Soft tissue evaluation of functional therapy in growing patients with class II malocclusion: mandibular advancement vs. twin block-a retrospective study.

Objective: The aim of this retrospective study was to assess the soft tissues changes resulting from Class II treatment with functional appliances (Twin Block vs. Mandibular Advancement), when compared to an untreated Class II control group.

Materials and methods: The records of 45 Class II patients who underwent treatment with Twin Block (TB group: n = 22; mean age: 11.3 ± 1.4 years) or Mandibular Advancement (MA group: n = 23; mean age: 11.2 ± 1.3 years) were analyzed in comparison with a control sample of untreated Class II subjects (Untreated Control group = 24; mean age: 11.2 ± 1.1 years). The data were collected before treatment (T1) and at the conclusion of the functional therapy phase (T2). Cephalometric modifications were assessed among the three groups using ANOVA and Tukey's post hoc tests.

Results: Significant improvements were observed for mandibular sulcus and the facial profile angle in the treated groups compared to the Untreated control group (facial profile angle: TB group: +5.67°; MA group: +6.34°; mandibular sulcus: TB group: +10.0°; MA group: 11.77°). The distance of Pogonion (Pg) to the True Vertical Line (TVL) exhibited significant differences among the three groups, with a more pronounced advancement of the soft tissue pogonion in the TB group (TVL-Pg': TB group: +3 mm; MA group: +0.9 mm; untreated control group: -1.6 mm).

Conclusions: Treatment with removable functional devices (TB or MA) during puberty produced beneficial effects on the soft tissue profile. Both treated groups demonstrated a significant improvement in the Class II convex profile, accompanied by a less evident mandibular sulcus.