title: [Dihydrotestosterone improves the osseointegration of                     cobalt-chromium implants].
abstract: BACKGROUND
  The osseointegration of actually rarely implanted cobalt-chromium implants can be critical in an elderly population. The aim of our study was to evaluate the effect of preoperative testosterone treatment on the osseointegration of cobalt-chromium implants.
  
  
  METHODS
  Press-fit implantation of 1.6 mm-diameter cobalt-chromium-molybdenum (CoCrMo) implants was performed in rats without pre-treatment in one group (n = 10) and after pre-treatment with 1 mg dihydrotestosterone (DHT) 2 days before surgery in the other group (n = 10). After 14 days, the specimens were examined by a pull-out test, histology and histomorphometry.
  
  
  RESULTS
  The biomechanical testing delivered inconsistent data leading to no significant difference (6.45 ± 6.94 N vs. 4.66 ± 3.77 N). Histology showed closed contact between surrounding tissue and the implants in both groups. The bone/implant contact area was significantly enhanced after treatment with DHT (42.23 % ± 9.25 vs. 57.57 % ± 16.71, p < 0.05), while the ratio of osteoid was reduced (38.68 % ± 16.7 vs. 27.38 % ± 13.02, not significant).
  
  
  CONCLUSIONS
  Pre-treatment with DHT enhances osseointegration of cobalt-chromium implants through enhanced mineralisation of peri-implant tissue. The treatment might additionally shorten postoperative rehabilitation due to its positive effects on musculature.
authors: Orthopädisches Zentrum, St. Antonius-Stift, Emstek. uwe.maus@kk-om.de
authors: U M
authors: UM
authors: Maus
authors: M
authors: M
authors: Lühmann
authors: J A K
authors: JA
authors: Ohnsorge
authors: S
authors: S
authors: Andereya
authors: H
authors: H
authors: Schmidt
authors: G
authors: G
authors: Zombory
authors: C
authors: C
authors: Siebert
authors: C
authors: C
authors: Niedhart
mesh_terms: D000818:Animals; D002858:Chromium Alloys; D013196:Dihydrotestosterone / Q000008:administration & dosage*; D005269:Femur / Q000187:drug effects / Q000503:physiopathology* / Q000601:surgery*; D016348:Osseointegration / Q000187:drug effects*; D019736:Prostheses and Implants; D051381:Rats; D017207:Rats, Sprague-Dawley; D016896:Treatment Outcome
chemical_list: D002858:Chromium Alloys; D013196:Dihydrotestosterone