title: External root resorption with the self-ligating Damon system-a retrospective study.
abstract: BACKGROUND
  The aim of this study was to compare the degree of external apical root resorption (EARR) in patients treated with self-ligating Damon appliances and with conventional preadjusted appliances.
  
  
  METHODS
  The sample comprised 52 patients, divided into two groups. Group 1 consisted of 25 patients treated with self-ligating Damon appliances, with an initial age of 16.04 years, final age of 18.06 years, and treatment time of 2.02 years. Group 2 consisted of 27 patients, treated with conventional preadjusted appliances, with an initial age of 16.77 years, final age of 18.47 years and treatment time of 1.70 years. The groups were matched regarding the initial and final ages, treatment time, type of malocclusion, and treatment protocol without extractions. Root resorption was evaluated on periapical radiographs of the maxillary and mandibular incisors at the end of orthodontic treatment with the scores of Levander and Malmgren. Intergroup comparisons of root resorption were performed with Mann-Whitney tests.
  
  
  RESULTS
  No significant difference in the degree of root resorption between the two groups was found.
  
  
  CONCLUSIONS
  Similar degrees of resorption can be expected after non-extraction treatment with Damon self-ligating or conventional preadjusted appliances.
authors.affiliation: Department of Stomatology and Radiology, Bauru Dental School, University of São Paulo, Bauru, Brazil.
authors.forename: Roberta Heiffig
authors.initials: RH
authors.lastname: Handem
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, SP, 17012-901, Brazil.
authors.forename: Guilherme
authors.initials: G
authors.lastname: Janson
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, SP, 17012-901, Brazil. mts78@usp.br.
authors.forename: Murilo
authors.initials: M
authors.lastname: Matias
authors.affiliation: Department of Orthodontics, Ingá Dental School, Maringá, Brazil.
authors.forename: Karina Maria Salvatore
authors.initials: KM
authors.lastname: de Freitas
authors.affiliation: Private practice, Cuiabá, Brazil.
authors.forename: Darwin Vaz
authors.initials: DV
authors.lastname: de Lima
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, SP, 17012-901, Brazil.
authors.forename: Daniela Gamba
authors.initials: DG
authors.lastname: Garib
authors.affiliation: Department of Orthodontics, Bauru Dental School, University of São Paulo, Alameda Octávio Pinheiro Brisolla 9-75, Bauru, SP, 17012-901, Brazil.
authors.forename: Marcos Roberto
authors.initials: MR
authors.lastname: de Freitas
mesh_terms: D000293:Adolescent; D005260:Female; D006801:Humans; D007180:Incisor / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D008310:Malocclusion / Q000628:therapy; D008311:Malocclusion, Angle Class I / Q000628:therapy; D008334:Mandible / Q000000981:diagnostic imaging; D008437:Maxilla / Q000000981:diagnostic imaging; D016382:Orthodontic Appliance Design; D016910:Orthodontic Brackets / Q000009:adverse effects*; D009969:Orthodontic Wires / Q000009:adverse effects; D009971:Orthodontics, Corrective / Q000009:adverse effects* / Q000295:instrumentation / Q000379:methods; D011859:Radiography; D012189:Retrospective Studies; D012391:Root Resorption / Q000000981:diagnostic imaging / Q000209:etiology*; D013193:Stainless Steel / Q000737:chemistry; D018709:Statistics, Nonparametric; D013314:Stress, Mechanical; D019227:Tooth Apex / Q000000981:diagnostic imaging / Q000473:pathology*; D014087:Tooth Movement Techniques / Q000009:adverse effects / Q000295:instrumentation
chemical_list: D013193:Stainless Steel
keywords: Orthodontic; Periapical radiograph; Root resorption; Self-ligating