title: Autogenous bone and a bovine bone substitute for ridge preservation: preliminary clinical and histologic findings.
abstract: BACKGROUND
  Tooth extractions lead to morphological changes of the alveolar ridge. For oral rehabilitation sufficient bone volume of the alveolar ridge is required. This clinical study compared the ability of Bio-Oss®Collagen to autogenous bone to preserve bone volume after tooth extraction.
  
  
  METHODS
  A total of 17 patients with 20 extraction sites were examined. After extraction, 10 sockets were each filled with either autogenous bone or Bio-Oss®Collagen and covered with a resorbable membrane. The width of the alveolar ridge was measured postoperatively, and after 4 and 6 months respectively. Prior to implant insertion, a bone biopsy was taken from the grafted sites and evaluated histologically.
  
  
  RESULTS
  The width of the alveolar ridge in the Bio-Oss®Collagen group decreased about 5.33 ± 6.62% after 4 months and 9.45 ± 10.51% after 6 months. The reduction in the group augmented with autogenous bone was 14.31 ± 21.41% after 4 months and 19.17 ± 8.38% after 6 months. No statistically significant differences were observed. The histological examination showed comparable area fractions of total bone in both groups (Bio-Oss®Collagen: 59.99 ± 24.23%; autogenous bone: 61.55 ± 25.13%; p = 1.0).
  
  
  CONCLUSIONS
  The present study demonstrated that autogenous bone and Bio-Oss®Collagen are suitable for ridge preservation. However, both techniques could not entirely prevent tissue volume loss.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine 'Carl Gustav Carus', Technische Universität Dresden, Dresden, Germany.
authors.forename: M C
authors.initials: MC
authors.lastname: Schulz
authors.affiliation: Private Practice, Kirchberg, Germany.
authors.forename: M B
authors.initials: MB
authors.lastname: Kallweit
authors.affiliation: Private Practice, Kirchberg, Germany.
authors.forename: S
authors.initials: S
authors.lastname: Kallweit
authors.affiliation: Institute for Medical Informatics and Biometry, Faculty of Medicine 'Carl Gustav Carus', Technische Universität Dresden, Dresden, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Koch
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine 'Carl Gustav Carus', Technische Universität Dresden, Dresden, Germany.
authors.forename: G
authors.initials: G
authors.lastname: Lauer
authors.affiliation: Department of Oral and Maxillofacial Surgery, Faculty of Medicine 'Carl Gustav Carus', Technische Universität Dresden, Dresden, Germany.
authors.forename: R
authors.initials: R
authors.lastname: Mai
authors.affiliation: Department of Periodontology, Faculty of Medicine 'Carl Gustav Carus', Technische Universität Dresden, Dresden, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Hoffmann
keywords: Autogenous bone; bone substitutes; clinical research; histology; wound healing