title: Ridge alterations following grafting of fresh extraction sockets in man. A randomized clinical trial.
abstract: OBJECTIVE
  To evaluate dimensional alterations of the alveolar ridge that occurred following tooth extraction at sites grafted with Bio-Oss(®) Collagen.
  
  
  METHODS
  Twenty-eight subjects with maxillary incisors, canines, and premolars scheduled for extraction were included. The tooth was carefully removed. The patients were randomly assigned to a test or a control group. In the test group patients, Bio-Oss(®) Collagen was placed in the fresh extraction socket while in the controls no grafting was performed. Radiographic examination (cone beam computed tomograms, CBCT) was performed immediately after tooth extraction and socket treatment. Four months later, a new CBCT was obtained. In the radiographs, (i) the distance (mm) between base of the alveolar process (apex) and the buccal and palatal crests was determined, (ii) the outer profile of alveolar process of the experimental sites was outlined, and the cross section of the area (mm(2) ) determined.
  
  
  RESULTS
  After 4 months of healing, the buccal and to a less extent also the palatal bone plate had become markedly reduced in height. The placement of a biomaterial in the socket failed to prevent resorption of the buccal and palatal bone walls. The cross-sectional area of the control ridge was reduced about 25% and of the test ridge with 3%.
  
  
  CONCLUSIONS
  The placement of a xenograft in fresh extraction sockets markedly counteracted the reduction in the hard tissue component of the edentulous sites.
authors.affiliation: Department of Dentistry, State University of Maringá, Parana, Brazil.
authors.forename: Mauricio G
authors.initials: MG
authors.lastname: Araújo
authors.affiliation: Private practice, Bahia, Brazil.
authors.forename: João Carlos Costa
authors.initials: JCC
authors.lastname: da Silva
authors.affiliation: Department of Prosthodontics, State University of Rio de Janeiro, Rio de Janeiro, Brazil.
authors.forename: Arthur Furtado
authors.initials: AF
authors.lastname: de Mendonça
authors.affiliation: Institute of Odontology, The Sahlgrenska Academy at the University of Gothenburg, Gothenburg, Sweden.
authors.forename: Jan
authors.initials: J
authors.lastname: Lindhe
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000000981:diagnostic imaging*; D018786:Bone Substitutes / Q000627:therapeutic use*; D054893:Cone-Beam Computed Tomography; D005260:Female; D064593:Heterografts; D006801:Humans; D008297:Male; D008437:Maxilla / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D008903:Minerals / Q000627:therapeutic use*; D014081:Tooth Extraction; D020390:Tooth Socket / Q000000981:diagnostic imaging / Q000601:surgery*; D016896:Treatment Outcome; D014945:Wound Healing
chemical_list: C077540:Bio-Oss; D018786:Bone Substitutes; D008903:Minerals
keywords: biomaterial; bone formation; extraction socket; grafting; humans; xenograft