title: Root resorption diagnosed with cone beam computed tomography after 6 months of orthodontic treatment with fixed appliance and the relation to risk factors.
abstract: OBJECTIVE
  To investigate root resorption after 6 months of active orthodontic treatment and its relation to possible risk factors.
  
  
  METHODS
  Ninety-seven patients (10-18 years) with a Class I malocclusion and crowding treated with fixed appliance and premolar extractions were examined with cone beam computed tomography before and after 6 months of active treatment. The exposure covered all teeth from first molar to first molar in both jaws. The Malmgren index was used to evaluate the degree of root resorption. Irregular root contour (score 1) was seen in most teeth already before active treatment, and therefore resorptions were registered only as score 2 (<2 mm, minor resorption) or higher.
  
  
  RESULTS
  Minor root resorption was noted in 10% of the patients and severe root resorption, >2 mm (score 3) was found in four patients. Root resorption was more frequently seen in the upper jaw, especially the incisors. There was no statistically significant correlation of root resorption with any of the selected risk factors.
  
  
  CONCLUSIONS
  After 6 months of treatment, clinically significant resorption was diagnosed in 4% of the patients, ie, in 96% of the patients the radiographic examination did not reveal any significant information. The selected risk factors did not have any impact on the amount of resorption after 6 months of active treatment.
authors.affiliation: Department of Orthodontics, Institute of Odontology, Sahlgrenska Academy at University of Gothenburg, Sweden. dmakedonas@hotmail.com
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Makedonas
authors.forename: Henrik
authors.initials: H
authors.lastname: Lund
authors.forename: Kerstin
authors.initials: K
authors.lastname: Gröndahl
authors.forename: Ken
authors.initials: K
authors.lastname: Hansen
mesh_terms: D000293:Adolescent; D001641:Bicuspid / Q000601:surgery; D002648:Child; D054893:Cone-Beam Computed Tomography; D003481:Cuspid / Q000000981:diagnostic imaging; D005386:Fingersucking / Q000009:adverse effects; D005500:Follow-Up Studies; D006801:Humans; D007180:Incisor / Q000000981:diagnostic imaging; D008311:Malocclusion, Angle Class I / Q000628:therapy; D008334:Mandible / Q000000981:diagnostic imaging; D008437:Maxilla / Q000000981:diagnostic imaging; D008963:Molar / Q000000981:diagnostic imaging; D009259:Nail Biting / Q000009:adverse effects; D016910:Orthodontic Brackets; D019516:Orthodontic Space Closure / Q000295:instrumentation; D009969:Orthodontic Wires; D012307:Risk Factors; D012391:Root Resorption / Q000145:classification / Q000000981:diagnostic imaging*; D014081:Tooth Extraction; D018677:Tooth Injuries / Q000150:complications; D014087:Tooth Movement Techniques / Q000295:instrumentation; D014092:Tooth Root / Q000002:abnormalities