title: Laboratory-made space maintainers: a 7-year retrospective study from private pediatric dental practice.
abstract: OBJECTIVE
  The purpose of this study was to report survival times and problems encountered with laboratory made space maintainers placed over 7 years by one pediatric dentist.
  
  
  METHODS
  Charts were reviewed for 235 patients with fixed space maintainers placed between January 1, 1997, and December 31, 2003, and followed to December 31, 2005. Problems encountered and appliance lifetimes were recorded and assessed. Failures were recorded as: (1) cement loss; (2) solder breakage; (3) split bands; (4) eruption interference; (5) bent wire; (6) complete loss; or (7) not specified. Appliance outcomes, transferred patients, and those lost to follow-up were recorded.
  
  
  RESULTS
  A total of 323 appliances were followed, with: (a) 93 (29%) successes; (b) 110 (34%) still in service; and (c) 104 (32%) known failures. Of the latter, most (62%) were from cement loss (60%) and 13 (12%) were totally lost. No statistically significant differences were noted between types of appliances, gender, and types of failure, except for the fact that bands and loops exhibited more cement loss (P=.045). Mean pooled survival times were between 26 and 27 months.. Of the 104 failures: (a) 34 (33%) were no longer needed (being considered clinically successful); (b) 57 (55%) were recemented; and (c) 13 (12%) were remade. Sixteen appliances were lost to follow-up or transferred.
  
  
  CONCLUSIONS
  A total of 63% of all space maintainers lasted their anticipated lifetimes or were still in use.
authors.affiliation: Boston University, Boston, MA, USA.
authors.forename: Mehrdad
authors.initials: M
authors.lastname: Fathian
authors.forename: David B
authors.initials: DB
authors.lastname: Kennedy
authors.forename: M Reza
authors.initials: MR
authors.lastname: Nouri
mesh_terms: D000293:Adolescent; D002170:Canada; D002648:Child; D003724:Dental Arch / Q000033:anatomy & histology; D004868:Equipment Failure / Q000706:statistics & numerical data; D005500:Follow-Up Studies; D006801:Humans; D008334:Mandible; D008437:Maxilla; D016382:Orthodontic Appliance Design; D018704:Orthodontic Retainers / Q000145:classification / Q000706:statistics & numerical data*; D010377:Pediatric Dentistry / Q000295:instrumentation* / Q000379:methods / Q000706:statistics & numerical data; D012189:Retrospective Studies; D013027:Space Maintenance, Orthodontic / Q000295:instrumentation* / Q000706:statistics & numerical data; D016019:Survival Analysis; D014085:Tooth Migration / Q000517:prevention & control*; D014094:Tooth, Deciduous; D016896:Treatment Outcome