title: Effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors.
abstract: The purpose of this study was to compare the effects of active and passive lacebacks on antero-posterior position of maxillary first molars and central incisors during leveling phase. Twenty-three subjects with Class I and Class II malocclusion were treated with first premolars extraction using preadjusted appliances (MBT 0.022-inch brackets). The leveling phase was performed with stainless steel archwires only. The sample was divided into 2 groups: 14 subjects received active lacebacks (Group 1) and 9 subjects received passive lacebacks (Group 2). Lacebacks were made from 0.008-inch ligature wire. Lateral cephalometric radiographs were taken pre- and post-leveling phase. Student's t-test was applied to determine the differences between pre- and post-leveling mean values and to determine the mean differences between groups. In Group I, the first molars showed a significant mesial movement, whereas no change was observed in Group 2. In both groups, maxillary central incisor crowns moved to lingual side. In conclusion, active laceback produced anchorage loss of maxillary first molars whereas passive laceback did not affect the position of these teeth. Active and passive lacebacks were effective in preventing central incisor proclination.
authors.affiliation: Positivo University, Curitiba, PR, Brazil. ricardo@moresca.com.br
authors.forename: Ricardo Cesar
authors.initials: RC
authors.lastname: Moresca
authors.forename: Julio Wilson
authors.initials: JW
authors.lastname: Vigorito
authors.forename: Gladys Cristina
authors.initials: GC
authors.lastname: Dominguez
authors.forename: André
authors.initials: A
authors.lastname: Tortamano
authors.forename: Danielle Rodrigues
authors.initials: DR
authors.lastname: Moraes
authors.forename: Alexandre
authors.initials: A
authors.lastname: Moro
authors.forename: Gisele Maria
authors.initials: GM
authors.lastname: Correr
mesh_terms: D000293:Adolescent; D001641:Bicuspid / Q000601:surgery; D002508:Cephalometry / Q000379:methods; D002648:Child; D003722:Dental Alloys / Q000737:chemistry; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000473:pathology*; D008297:Male; D008311:Malocclusion, Angle Class I / Q000628:therapy; D008312:Malocclusion, Angle Class II / Q000628:therapy; D008437:Maxilla; D008963:Molar / Q000473:pathology*; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D009969:Orthodontic Wires; D013193:Stainless Steel / Q000737:chemistry; D019228:Tooth Crown / Q000473:pathology; D014081:Tooth Extraction; D014087:Tooth Movement Techniques / Q000295:instrumentation*; D014092:Tooth Root / Q000473:pathology
chemical_list: D003722:Dental Alloys; D013193:Stainless Steel