title: Frequency of and complications in the use of RPE appliances--results of a survey in the Federal State of Hesse, Germany.
abstract: OBJECTIVE
  A questionnaire was sent to orthodontists with private practices in the German State of Hesse to obtain information about the frequency of rapid palatal expansion and complications during treatment with rapid palatal expansion appliances (RPE-A).
  
  
  METHODS
  A series of questions therein inquired as to the types of RPE-As used, their activation rhythm, the extent and the duration of the active expansion and retention; what their age limit was, starting from when surgical assistance was deemed necessary. Another series of queries concerned any technical and medical complications observed.
  
  
  RESULTS
  The most frequently used type was the Hyrax screw (75%) soldered to bands. Technical problems arose with all applied indicated types. Although the answers to the first series of questions showed great variance, the majority of the orthodontists activated the screw twice a day (range 1-6 times a day) by a quarter turn for 2-3 (range 1-12) weeks. The retention phase amounted to 12 (range 4-26) weeks and the age limit for the indication of a surgical intervention was on average 17 years, with a range of 10-35 years. Medical complications such as pain and decubitae were reported by a third of the inquired offices, a non-opening suture was observed in one of every five practices. This meant that 1.7% of the sutures failed to open, and tooth tilting and rarely, extreme root resorptions and/or bone dehiscences were observed. Solid carious lesions were observed in one case after removal of an adhesive RPE. Extraoral changes such as those in the nose were reported by one in every ten practices.
  
  
  CONCLUSIONS
  The RPE represents a common treatment means during which side effects are often temporary and permanent damages rather rare. It is important to inform the patient about both positive effects and possible complications, in particular pain and extraoral changes.
authors.affiliation: Department of Orthodontics, ZZMK, 60590, Frankfurt/M., Germany. g.schuster@em.uni-frankfurt.de
authors.forename: Gabriele
authors.initials: G
authors.lastname: Schuster
authors.forename: Iris
authors.initials: I
authors.lastname: Borel-Scherf
authors.forename: Peter M
authors.initials: PM
authors.lastname: Schopf
mesh_terms: D000293:Adolescent; D015897:Comorbidity; D003625:Data Collection; D005157:Facial Pain / Q000453:epidemiology*; D005260:Female; D005858:Germany / Q000453:epidemiology; D006801:Humans; D008297:Male; D009967:Orthodontic Appliances / Q000706:statistics & numerical data*; D017063:Outcome Assessment, Health Care / Q000379:methods*; D010155:Palatal Expansion Technique / Q000295:instrumentation* / Q000706:statistics & numerical data*; D003668:Pressure Ulcer / Q000453:epidemiology*; D015995:Prevalence; D011331:Private Practice / Q000706:statistics & numerical data; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D016896:Treatment Outcome