Investigation of stability of orthopedic treatment results in skeletal class II patients due to lower jaw

Objective: The aim of this study was; monoblock, twin block and Herbst apparatus in patients treated with lateral cephalometric films to examine the changes that occur. Method: In this follow-up study, clinical and cephalometric controls were performed at least 1 year after the end of functional treatment of individuals with different growth and developmental stages who had received functional orthopedic treatment for amandibular retardation. Prepeak twin block group, peak monoblock group and postpeak Herbst group, respectively; It consists of 21, 21 and 26 individuals. The follow-up periods after treatment were 2.65 ± 0.49 years for the twin block group, 3.21 ± 0.69 years for the monoblock group, and 3.53 ± 0.70 years for the Herbst group. Differences between the three groups (T1-T0) were analyzed by one-way analysis of variance (ANOVA). Subgroup analysis of differences between groups was performed by Mann-Whitney U test. Results: In cephalometric evaluation; ANB and Witt's values were stable in all groups approximately 3 years (2.6-3.5 years) after functional treatment (p> 0.05). Maxillary and mandibular dimensional measurements were increased due to the effect of growth in twin block and monoblock groups. In all three groups, dentoalveolar changes occurred due to constant treatment and growth and development effect. Recurrence of overjet was the highest in Herbst group due to dentoalveolar changes (p <0.05). Conclusion: Twin block and monoblock apparatus applied during the developmental period and the skeletal changes obtained with the Herbst apparatus applied during the last stage of the development were largely preserved at the end of the follow-up period. Key Words: mandibular retrognati, relapse in functional therapy, growth and development.