Abstract
BACKGROUND: Long-term stability following orthodontic correction of Class II malocclusion is often compromised by soft tissue dysfunctions, particularly improper tongue posture. Tongue posture training has been hypothesized to contribute to posttreatment stability by promoting functional harmony in the orofacial musculature. OBJECTIVE: This prospective study aimed to evaluate the effect of tongue posture training on the long-term stability of orthodontic outcomes in patients with Class II malocclusion. MATERIALS AND METHODS: A total of 60 patients with skeletal Class II malocclusion, aged between 12 and 18 years, were enrolled and randomly divided into two groups: Group A (n = 30) received comprehensive fixed orthodontic treatment along with tongue posture training exercises; Group B (n = 30) received only orthodontic treatment. Posttreatment stability was assessed at six and 12 months using cephalometric parameters and Peer Assessment Rating (PAR) scores. Data were analyzed using independent t-tests and repeated-measures ANOVA. RESULTS: At the 12-month follow-up, Group A showed significantly lower relapse rates, with a mean change in PAR score of 1.8 ± 1.2 compared to 3.9 ± 1.5 in Group B (P < 0.001). Cephalometric analysis revealed more stable incisor positioning and mandibular advancement in Group A (IMPA: 98.3° ±2.4 vs. 94.7° ±3.1; P = 0.002). Tongue-to-palate contact time increased significantly in Group A (17.5 ± 3.2 hours/day) versus Group B (10.8 ± 2.7 hours/day; P < 0.001). CONCLUSION: Tongue posture training significantly enhances the posttreatment stability of orthodontic correction in Class II malocclusion. Incorporating orofacial myofunctional therapy into orthodontic protocols may yield more stable long-term outcomes.