A comparison of the skeletal, dental, and soft tissue effects caused by herbst and mandibular protraction appliances in the treatment of mandibular Class II malocclusions.

This lateral-view cephalometric study compares the skeletal, dental, and soft tissue effects in patients with Class II mandibular malocclusions undergoing treatment with the Herbst appliance and the mandibular protraction appliance. The sample consists of 43 adolescents, divided into 3 groups: group 1, 12 individuals, average age 12 years 4 months, treated with the Herbst appliance for an average of 8.7 months; group 2, 15 individuals, average age 13 years 2 months, treated with the mandibular protraction appliance for an average of 8.3 months; and group 3 (control), 16 individuals, average age 10 years 4 months, who did not undergo any treatment and were followed for a period of 10 months. Based on the results, both treatment groups showed: (1) greater increases in the mandibular length than the controls, with the MPA-treated group displaying significantly more growth than the Herbst-treated group; (2) a vestibular inclination of the mandibular incisors; (3) retrusion of the upper lip. No other significant soft tissue or dental differences manifested among the 3 groups.