title: The effect of zigzag elastics in the treatment of Class II division 1 malocclusion subjects with hypo- and hyperdivergent growth patterns. A pilot study.
abstract: The aim of this study was to investigate the effect of zigzag elastics in the treatment of Class II division 1 malocclusion subjects with hypo- or hyperdivergent growth patterns. Two groups were established, each consisting of 10 subjects classified as hypo- or hyperdivergent according to their pre-treatment SN-GoGn angle. The cephalometric radiographs taken before and after an elastic application period of approximately 4 months were used to generate 22 variables. In both groups, there were no statistically significant differences in the vertical position of the lower molars, the SN-GoGn angle or the inclination of the lower incisors, whereas the sagittal skeletal relationship was improved as a result of an increase in the SNB angle and the mandibular length (P < 0.01). Upper incisor extrusion was statistically significant in both groups (P < 0.05). The downward rotation of the occlusal plane and the increase in overbite were found to be significant in the hypodivergent group (P < 0.05). Significant differences were observed between the groups in the extrusion of the upper incisor, the inclination of the occlusal plane, and the amount of overbite (P < 0.05). The results show that the zigzag elastic system is preferable, especially in hyperdivergent Class II division 1 subjects, as the use of such elastics does not cause an unfavourable effect on vertical jaw base relationship.
authors.affiliation: Department of Orthodontics, University of Ege, Turkey.
authors.forename: A
authors.initials: A
authors.lastname: Aras
authors.forename: A
authors.initials: A
authors.lastname: Cinsar
authors.forename: H
authors.initials: H
authors.lastname: Bulut
mesh_terms: D000293:Adolescent; D002508:Cephalometry; D002648:Child; D002680:Chin / Q000473:pathology; D003722:Dental Alloys; D003766:Dental Occlusion; D005115:Extraoral Traction Appliances; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology; D008297:Male; D008312:Malocclusion, Angle Class II / Q000503:physiopathology / Q000628:therapy*; D008334:Mandible / Q000473:pathology; D008445:Maxillofacial Development; D008963:Molar / Q000473:pathology; D009295:Nasal Bone / Q000473:pathology; D009532:Nickel; D016382:Orthodontic Appliance Design; D009967:Orthodontic Appliances; D009969:Orthodontic Wires; D011446:Prospective Studies; D012399:Rotation; D012658:Sella Turcica / Q000473:pathology; D013193:Stainless Steel; D013223:Statistics as Topic; D018709:Statistics, Nonparametric; D014025:Titanium; D014087:Tooth Movement Techniques / Q000295:instrumentation / Q000379:methods; D014716:Vertical Dimension
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium