title: Physical properties of root cementum: Part 25. Extent of root resorption after the application of light and heavy buccopalatal jiggling forces for 12 weeks: A microcomputed tomography study.
abstract: BACKGROUND
  The aims of this study were to evaluate with microcomputed tomography the orthodontically induced inflammatory root resorption in premolars caused by buccopalatal jiggling movement with light and heavy forces and to compare it with the resorption caused by equivalent but continuous buccal forces.
  
  
  METHODS
  The sample consisted of 60 maxillary first premolars collected from 30 patients (15 girls, 15 boys; ages, 13-18 years) who required orthodontic treatment with extractions. They were divided into 3 groups of 10 patients. Light (25 g) or heavy (225 g) buccal tipping orthodontic forces were randomly assigned on the maxillary right or left quadrant with either continuous buccal (positive controls) or buccopalatal jiggling forces for 12 weeks. At the end of the experimental period, the teeth were carefully extracted and processed for 3-dimensional imaging and volumetric evaluations of resorption craters. Data were analyzed with Wilcoxon signed rank tests.
  
  
  RESULTS
  There was no statistically significant difference between positive control light (P = 0.0173) and heavy (P = 0.0173) continuous forces and jiggling forces for both force magnitudes. However, statistically significant differences were observed between heavy and light jiggling forces (P = 0.038), with heavy jiggling forces causing greater total root resorption than light jiggling forces.
  
  
  CONCLUSIONS
  Light and heavy jiggling forces in the buccopalatal direction did not cause significantly different amounts of root resorption when compared with continuous forces of the same magnitude. On the other hand, light jiggling forces resulted in less root resorption than heavy jiggling forces.
authors.affiliation: Postgraduate student, Department of Orthodontics, Semmelweis University, Budapest, Hungary.
authors.forename: Edina
authors.initials: E
authors.lastname: Eross
authors.affiliation: Professor, Department of Orthodontics, Faculty of Dentistry, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Tamer
authors.initials: T
authors.lastname: Turk
authors.affiliation: Associate professor, Department of Orthodontics, Faculty of Dentistry, Ondokuz Mayis University, Samsun, Turkey.
authors.forename: Selma
authors.initials: S
authors.lastname: Elekdag-Turk
authors.affiliation: Assistant professor, Department of Orthodontics, Faculty of Dentistry, Bülent Ecevit University, Zonguldak, Turkey.
authors.forename: Fethiye
authors.initials: F
authors.lastname: Cakmak
authors.affiliation: Associate professor, School of Medical and Molecular Biosciences, University of Technology, Sydney, Australia.
authors.forename: Allan S
authors.initials: AS
authors.lastname: Jones
authors.affiliation: Professor, Department of Orofacial Orthopedics and Orthodontics, Heim Pál Children's Hospital, Budapest, Hungary.
authors.forename: András
authors.initials: A
authors.lastname: Végh
authors.affiliation: Senior lecturer, Discipline of Orthodontics, Faculty of Dentistry, University of Sydney; Sydney Dental Hospital, Sydney South West Area Health Service, Sydney, Australia.
authors.forename: Alexandra K
authors.initials: AK
authors.lastname: Papadopoulou
authors.affiliation: Professor and chair, Discipline of Orthodontics, Faculty of Dentistry, University of Sydney; Sydney Dental Hospital, Sydney South West Area Health Service, Sydney, Australia. Electronic address: ali.darendeliler@sydney.edu.au.
authors.forename: M Ali
authors.initials: MA
authors.lastname: Darendeliler
mesh_terms: D000293:Adolescent; D001641:Bicuspid / Q000000981:diagnostic imaging; D001696:Biomechanical Phenomena; D003739:Dental Cementum / Q000000981:diagnostic imaging*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008297:Male; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets; D009969:Orthodontic Wires; D012391:Root Resorption / Q000000981:diagnostic imaging* / Q000209:etiology; D013314:Stress, Mechanical; D014087:Tooth Movement Techniques / Q000295:instrumentation*; D014092:Tooth Root / Q000000981:diagnostic imaging*; D055114:X-Ray Microtomography / Q000379:methods*