Abstract
Introduction The Herbst device is widely used for correction of class II malocclusions; however, most of the researches carried out on the Herbst appliance in literature do not take into account patients with a different mandibular divergence. The aim of this study was to investigate the effects of Herbst on dental and skeletal structures and to evaluate possible influence of vertical facial growth patterns. Methods A retrospective study was conducted on lateral cephalograms of 75 growing patients (mean age: 9.9 ± 1.9 years) with class II malocclusion treated with Herbst. Subjects were divided into 3 groups using the mandibular divergence index (SN and GoMe angle). Cephalometric parameters were evaluated using the modified SO (sagittal occlusion) Pancherz's analysis. A statistical analysis was conducted to evaluate differences among groups using ANOVA. Results Our study showed differences in response to treatment depending on patient's facial vertical growth pattern. Cranial base angle and mandibular rotation were significantly different (p < 0.05) between hypodivergent patients and normodivergent patients and between hypodivergent and hyperdivergent subjects. Conclusion Hypodivergent patients increased their mandibular divergence during treatment to a greater extent than normodivergents; moreover, hyperdivergent patients exhibited a decreased mandibular divergence at the end of the treatment.
Highlights
Bilateral class II malocclusion represents one of the main orthodontic problems affecting the world population, and it has been observed that this condition affects 27.2% of English adolescents [1], 36.3% of Italian adolescents [2], about 15% of the total United States population [3], and 27.0% of Chinese children [4].is sagittal malocclusion can be skeletal, dental, or combined
Sample size calculation was performed; estimate of standard deviation was based on data obtained from other 10 subjects who were followed in a preliminary study, considering mandibular divergence as the primary outcome
Herbst therapy has determined in the total sample a slight retreat of the upper maxilla, but no significant difference was observed at the end of the treatment
Summary
Bilateral class II malocclusion represents one of the main orthodontic problems affecting the world population, and it has been observed that this condition affects 27.2% of English adolescents [1], 36.3% of Italian adolescents [2], about 15% of the total United States population [3], and 27.0% of Chinese children [4].is sagittal malocclusion can be skeletal, dental, or combined. E Herbst device is one of the most common appliances for the treatment of skeletal and dental class II, consisting of a piston and a tube anchored to orthodontic bands (or to splints or to cobalt/chrome fusions), which keeps the jaw in a protracted position 24 hours a day [6] through a bilateral telescopic mechanism. Most of the studies carried out on the Herbst appliance do not take into account patients with a different mandibular divergence [15], which affects chin position [16], the direction of the condylar growth [17], and the shape of the jaw [18]. E aim of this study was to investigate the effect of the Herbst appliance on dental and skeletal levels and to evaluate the existing differences between patients with different vertical growth patterns
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
