title: A comparative evaluation of lingual retainer failure bonded with or without liquid resin.
abstract: OBJECTIVE
  To prospectively evaluate and compare the effect of liquid resin on lingual retainer failure after a 2-year follow-up.
  
  
  METHODS
  Fifty-two patients (26 males, 26 females) with a mean age of 18.3 ± 1.3 years at follow-up, were randomized into two groups: the resin group and the nonresin group. The lingual retainers in the resin group were bonded to the enamel surfaces with two-step bonding resin, Optibond FL, and Tetric EvoFlow. The nonresin group followed the same procedure of bonding retainers but without applying the Optibond FL. Retainer failure, calculus accumulation, and discoloration of composite pads adjacent to the retainers during the 2-year observation period were registered, compared, and statistically analyzed with a Fisher's exact test and chi-square test.
  
  
  RESULTS
  In the resin group, the incidence of retainer failure was 4% and occurred at the composite-wire interface; in the nonresin group, the incidence was 27% and occurred at the enamel-composite interface. The difference between the groups was statistically significant (P  =  .049). The incidences of calculus accumulation and discoloration adjacent to the composite pads were 27% and 69% (P  =  .003 and P < .001) higher in the nonresin group, respectively.
  
  
  CONCLUSIONS
  Application of resin in bonding of lingual retainers appears to reduce the incidence of retainer failure as well as the incidence of calculus accumulation and discoloration adjacent to the composite pads.
authors: Department of Orthodontics, Postgraduate Dental Education Center, Orebro, Sweden. farhan.bazargani@orebroll.se
authors: Farhan
authors: F
authors: Bazargani
authors: Sven
authors: S
authors: Jacobson
authors: Bertil
authors: B
authors: Lennartsson
mesh_terms: D000293:Adolescent; D003188:Composite Resins / Q000627:therapeutic use*; D001840:Dental Bonding / Q000379:methods*; D003773:Dental Plaque / Q000517:prevention & control; D019232:Dental Restoration Failure; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008422:Materials Testing; D016382:Orthodontic Appliance Design; D018704:Orthodontic Retainers; D009969:Orthodontic Wires; D016037:Single-Blind Method; D016019:Survival Analysis; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D003188:Composite Resins