title: Submucosal implantation of soft tissue expanders does not affect microcirculation.
abstract: OBJECTIVE
  To investigate the effect of submucosal implantation of self-filling osmotic tissue expanders on mucosal microcirculation.
  
  
  METHODS
  In ten beagle dogs, all premolars were extracted on both sides of the mandible. Tooth-supporting bone and excess soft tissue were removed to mimic a severely resorbed edentulous ridge. Six weeks later, tissue expanders with 0.7 ml final volume were implanted into a submucosal pouch at randomly selected test sites, while contralateral sites served as untreated controls. Microcirculation was assessed in perfusion units (PU) before surgery, after local anaesthesia, directly after surgery, and after 1 and 3 days, using Laser Doppler flowmetry.
  
  
  RESULTS
  Local anaesthesia caused a significant decrease of blood flow from baseline (zero) to -6.4 PU (median; Q1 -10.5; Q3 -0.9; P = 0.006); however, no additional significant decrease was recorded after completion of surgery. Blood flow showed significant increases to -3.6 PU (median; Q1 -11.3, Q3 2.1; P = 0.02) and -4.0 PU (median; Q1 -9.2, Q3 1.1; P = 0.013) after 1 and 3 days, respectively, when compared to the measurements obtained after application of local anaesthesia and completion of surgery. Blood flow had returned to unimpaired baseline levels 1 day after surgery (P > 0.05).
  
  
  CONCLUSIONS
  Submucosal implantation of self-filling osmotic tissue expanders results in only momentary disturbance of microcirculation. The minor impairment of perfusion may explain the consistently good outcomes of submucosal implantation of these tissue expanders.
authors.affiliation: Department of Periodontology, University of Witten/Herdecke, Witten, Germany.
authors.forename: Doğan
authors.initials: D
authors.lastname: Kaner
authors.forename: Han
authors.initials: H
authors.lastname: Zhao
authors.forename: Hendrik
authors.initials: H
authors.lastname: Terheyden
authors.forename: Anton
authors.initials: A
authors.lastname: Friedmann
mesh_terms: D000818:Animals; D004285:Dogs; D017078:Laser-Doppler Flowmetry; D008297:Male; D008833:Microcirculation; D009061:Mouth Mucosa / Q000098:blood supply*; D011474:Prosthesis Design; D015625:Tissue Expansion Devices
keywords: Laser Doppler flowmetry; microcirculation; soft tissue expansion; tissue expanders