title: Effect of lip bumpers on mandibular arch dimensions.
abstract: BACKGROUND
  The aim of this systematic review was to examine the effects of lip bumper therapy on mandibular arch dimensions.
  
  
  METHODS
  A literature survey of PubMed, EMBASE, Cochrane Central, and Cochrane Database of Systematic Reviews (www.cochrane.org) was conducted from December 1968 to January 2007. Human studies, randomized clinical trials, prospective and retrospective studies, and studies discussing the effect of lip bumpers on the arch and teeth were included. Two reviewers independently selected and extracted the data.
  
  
  RESULTS
  Of the 52 studies found in the search, only 1 met the inclusion criteria.
  
  
  CONCLUSIONS
  The results showed increases in arch dimensions that included an increase in arch length. This was attributed to incisor proclination, distalization, and distal tipping of the molars. There was also an increase in the arch width seen in the intercanine and deciduous intermolar and premolar distances. The long-term stability of the effects of the lip bumper need to be elucidated.
authors.affiliation: Department of Orthodontics and Dentofacial Orthopedics, Faculty of Dentistry, Cairo University, Cairo, Egypt.
authors.forename: Dena Ibrahim
authors.initials: DI
authors.lastname: Hashish
authors.forename: Yehya Ahmed
authors.initials: YA
authors.lastname: Mostafa
mesh_terms: D002508:Cephalometry; D003724:Dental Arch / Q000473:pathology*; D006801:Humans; D008046:Lip; D008334:Mandible / Q000473:pathology*; D016382:Orthodontic Appliance Design; D009967:Orthodontic Appliances; D009971:Orthodontics, Corrective / Q000295:instrumentation; D011446:Prospective Studies; D016032:Randomized Controlled Trials as Topic; D012189:Retrospective Studies