Giuca Maria Rita, Pasini Marco, Drago Sara, Del Corso Leonardo, Vanni Arianna, Carli Elisabetta, Manni Antonio
Department of Surgical, Medical, Molecular Pathology and Critical Area, Unit of Pediatric Dentistry, University of Pisa, Pisa, Italy.
Department of Orthodontics, School of Dentistry, University of Genova, Genova, Italy.
Int J Dent. 2020 Jan 11;2020:1018793. doi: 10.1155/2020/1018793. eCollection 2020.
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.
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.
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 ( < 0.05) between hypodivergent patients and normodivergent patients and between hypodivergent and hyperdivergent subjects.
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.
Herbst矫治器广泛用于矫治II类错牙合畸形；然而，文献中对Herbst矫治器进行的大多数研究并未考虑下颌差异不同的患者。本研究的目的是调查Herbst矫治器对牙齿和骨骼结构的影响，并评估垂直面部生长模式的可能影响。
对75例接受Herbst矫治器治疗的生长发育期II类错牙合畸形患者（平均年龄：9.9±1.9岁）的头颅侧位片进行回顾性研究。使用下颌差异指数（SN与GoMe角）将受试者分为3组。使用改良的SO（矢状牙合）Pancherz分析法评估头影测量参数。采用方差分析进行统计分析以评估组间差异。
我们的研究表明，根据患者的面部垂直生长模式，治疗反应存在差异。低角型患者与均角型患者之间以及低角型与高角型受试者之间，颅底角和下颌旋转存在显著差异（P<0.05）。
低角型患者在治疗期间下颌差异增加的程度大于均角型患者；此外，高角型患者在治疗结束时下颌差异减小。
