title: Effects on bone formation in ovariectomized rats after implantation of tooth ash and plaster of Paris mixture.
abstract: OBJECTIVE
  Our goal was to report on tooth ash and plaster of Paris mixture in bone defects in an ovariectomized rat osteoporosis model.
  
  
  METHODS
  Sixty rats were randomly assigned to 4 groups and each group was further divided into 3 subgroups: 4, 8, and 16 weeks after implantation. The defect was filled with different grafting conditions as follows: group 1, ovariectomy and nongraft group; group 2, ovariectomy and tooth ash-plaster graft group; group 3, nonovariectomy and nongraft group; and group 4, nonovariectomy and tooth ash-plaster graft group. Histologic sections and histomorphometric analysis of defects were obtained 4, 8, and 16 weeks after surgery.
  
  
  RESULTS
  For the 4-week ovariectomy group, there was significantly greater bone formation in tooth ash-plaster group compared with the nongraft group. In the nonovariectomy group, the tooth ash-plaster group also showed better bone formation than the nongraft group. However, there was no statistical significance. In both the ovariectomy and nonovariectomy groups, a significant increase in bone formation was observed according to the elapse of time. The nonovariectomy group showed increased new bone formation compared with the ovariectomy group, with the tooth ash-plaster group showing statistical significance in each subgroup (P =.048).
  
  
  CONCLUSIONS
  Ovariectomy acts as a negative factor in new bone formation. For a critical size bony defect, the tooth ash-plaster treatment of the osseous defect produces more stable, effective, and rapid new bone formation.
authors.affiliation: Oral Biology Research Institute, College of Dentistry, Chosun University, Gwangju, Korea.
authors.forename: So-Young
authors.initials: SY
authors.lastname: Kim
authors.forename: Su-Gwan
authors.initials: SG
authors.lastname: Kim
authors.forename: Sung-Chul
authors.initials: SC
authors.lastname: Lim
authors.forename: Chun-Sik
authors.initials: CS
authors.lastname: Bae
mesh_terms: D000818:Animals; D018786:Bone Substitutes / Q000627:therapeutic use*; D002133:Calcium Sulfate / Q000627:therapeutic use*; D004195:Disease Models, Animal; D005260:Female; D007091:Image Processing, Computer-Assisted; D008903:Minerals / Q000627:therapeutic use*; D010012:Osteogenesis / Q000502:physiology*; D010024:Osteoporosis / Q000473:pathology / Q000601:surgery*; D010052:Ovariectomy; D010053:Ovary / Q000502:physiology; D011897:Random Allocation; D051381:Rats; D017207:Rats, Sprague-Dawley; D012886:Skull / Q000473:pathology / Q000601:surgery*; D018709:Statistics, Nonparametric; D013997:Time Factors; D014070:Tooth / Q000737:chemistry*
chemical_list: D018786:Bone Substitutes; D008903:Minerals; D002133:Calcium Sulfate