title: Gingival labial recessions in orthodontically treated and untreated individuals: a case - control study.
abstract: OBJECTIVE
  To evaluate the long-term development of labial gingival recessions during orthodontic treatment and retention phase.
  
  
  METHODS
  In this retrospective case-control study, the presence of gingival recession was scored (Yes or No) on plaster models of 100 orthodontic patients (cases) and 120 controls at the age of 12 (T12 ), 15 (T15 ), 18 (T18 ), and 21 (T21 ) years. In the treated group, T12 reflected the start of orthodontic treatment and T15 - the end of active treatment and the start of retention phase with bonded retainers. Independent t-tests, Fisher's exact tests and a fitted two-part "hurdle" model were used to identify the effect of orthodontic treatment/retention on recessions.
  
  
  RESULTS
  The proportion of subjects with recessions was consistently higher in cases than controls. Overall, the odds ratio for orthodontic patients as compared with controls to have recessions is 4.48 (p < 0.001; 95% CI: 2.61-7.70).
  
  
  CONCLUSIONS
  Within the limits of the present research design, orthodontic treatment and/or the retention phase may be risk factors for the development of labial gingival recessions. In orthodontically treated subjects, mandibular incisors seem to be the most vulnerable to the development of gingival recessions.
authors.affiliation: Department of Orthodontics and Craniofacial Biology, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands.
authors.forename: Anne Marie
authors.initials: AM
authors.lastname: Renkema
authors.forename: Piotr S
authors.initials: PS
authors.lastname: Fudalej
authors.forename: Alianne A P
authors.initials: AA
authors.lastname: Renkema
authors.forename: Frank
authors.initials: F
authors.lastname: Abbas
authors.forename: Ewald
authors.initials: E
authors.lastname: Bronkhorst
authors.forename: Christos
authors.initials: C
authors.lastname: Katsaros
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D005260:Female; D005889:Gingival Recession / Q000209:etiology* / Q000473:pathology; D006801:Humans; D016015:Logistic Models; D008137:Longitudinal Studies; D008297:Male; D016017:Odds Ratio; D009967:Orthodontic Appliances / Q000009:adverse effects*; D009971:Orthodontics, Corrective / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors; D055815:Young Adult