Abstract
The present study was carried out to evaluate the benefits from one-phase Class II Early Treatment (ET) using extraoral forces and functional appliances but without intermaxillary forces and eventual lower leeway space preservation compared to two-phase Class II Late Treatment (LT) with the need for extractions and full fixed appliances as well as lower incisor proclination. The ET group (n = 239, 115 M, 124 F, mean age 10.6 ± 1.2 years), with first premolars not in contact and the second deciduous lower molars preserved, was compared to the LT group (n = 288, 137 M, 151 F, mean age 12.4 ± 1.5 years). The ET group was first treated with headgears, growth guide appliances, or Teuscher activators and, in borderline crowding cases, with lower space maintenance by a lingual arch, lip bumper, or fixed utility arch. The LT group and the second phase of ET were treated with full fixed appliances including intermaxillary forces such as Class II elastics or noncompliance devices; headgear and a growth guide appliance were also used. Cephalograms and plaster models were taken before (T1) and after treatment (T2) to calculate cephalometric changes and space balance discrepancies. The differences between T1 and T2 were analyzed by a t-test for normally distributed data and by the Mann–Whitney Test for nonnormally distributed data at a level of p < 0.05. The groups were defined as statistically homogeneous at T1. A statistical analysis showed that the ET group (mean treatment time 35.3 ± 13.3 months) was significantly associated with a 22.2% lower extraction rate, 15.9% less need for a full fixed appliance, and more than 5° less incisor proclination in the nonextraction cases compared to the LT group (mean treatment time 25.9 ± 8.1 months); treatment time significantly increased in the ET group compared to the LT group. Early Class II treatment resulted in a significant treatment effort reduction in more than one third of the patients and less lower incisor proclination, even if it clinically increased treatment time.
Highlights
Class II malocclusion is certainly the most frequent malocclusion in the Western world, and it represents a percentage of about 25–30% of the malocclusions of the orthodontic population [1]
For allocation to the Early Treatment (ET) group, the first permanent premolars must not have been in occlusal contact at treatment start, and the second deciduous molars must have been preserved in case of lower crowding
The limited scientific evidence may be due to the definition of “early treatment”, which includes different periods from primary, through early and late mixed dentition; including such a large period can lead to different results
Summary
Class II malocclusion is certainly the most frequent malocclusion in the Western world, and it represents a percentage of about 25–30% of the malocclusions of the orthodontic population [1]. Its etiology is multifactorial, being caused by skeletal or dental factors or their combination [2]. A diagnosis of Class II typically might determine the presence of maxillary prognathism and/or mandibular retrognathism, together with a variation in the occlusion and inclination of the teeth [3]. Mandibular retrusion is a common finding, as are pronounced overjet and prominent maxillary incisors with incomplete lip closure, with an increased risk for dental trauma and functional alterations [4]. A correct diagnosis to decide the most appropriate treatment plan should consider the interarch relationships and skeletal discrepancy, age, and patient compliance. Headgears are commonly used in orthodontic treatment among children with a
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
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 call
