Long-term evaluation (10 years) of the outcomes of Herbst functional appliance in pharyngeal dimensions and hyoid bone position.

OBJECTIVE

This study aimed to evaluate the long-term changes in the pharyngeal dimensions and hyoid bone position in Class II malocclusion patients treated with Herbst functional appliance.

MATERIAL AND

METHODS

The sample comprised 15 skeletal Class II malocclusion patients (13.00 ± 1.21 years) treated with Herbst functional appliance and followed for a mean period of 10 years (10.73 ± 3.67 years). Lateral headfilms were used to evaluate the pharyngeal dimensions and hyoid bone position, and the measurements were performed with Dolphin Imaging 11.9. Intragroup comparison between the evaluation stages was performed with repeated measures ANOVA, followed by Tukey tests if necessary. Results were considered statistically significant at p<0.05.

RESULTS

Regarding the pharyngeal cephalometric variables, only the hipo pharynx space increased significantly in the treatment period, and all of them remained stable remained stable during follow-up period. The hyoid bone moved significantly forward and downward during the treatment period and even further forward during the long-term posttreatment period.

CONCLUSION

The outcomes of Herbst functional appliance in pharyngeal dimensions and hyoid bone position are stable over the years.