title: Application of a new material (β-TCP/collagen composites) in extraction socket preservation: an experimental study in dogs.
abstract: OBJECTIVE
  A bone defect model simulating an extraction socket with buccal dehiscence was designed to investigate the usefulness of a composite of beta-tricalcium phosphate (β-TCP) and a collagen sponge, β-TCP/collagen (TCP/Col) for socket preservation.
  
  
  METHODS
  Following the extraction of the maxillary second and third premolars of 13 beagle dogs, a bone defect with buccal dehiscence (5 × 3 × 7 mm) was prepared. The defects were filled with either TCP/Col, ?-TCP, collagen, or left intact (control) and evaluated at 4 and 8 weeks after surgery. A total of three micro-computed tomography (micro-CT) images were selected, and the area size occupied by the newly formed bone and residual TCP was measured. Newly formed bone and residual TCP in the bone defect site of the specimens was also measured and evaluated.
  
  
  RESULTS
  No evidence of postoperative infection was found in all cases. At 4 weeks after surgery, the TCP granule was retained in the bone defects and active bone formation was observed in the TCP/Col group and the β-TCP group, whereas in the collagen and the control groups, connective tissue grew into the defect. In the TCP/Col and β-TCP groups, morphologically well-preserved alveolar ridges were observed; most TCP granules grafted in the defects were resorbed and only a few residuals were evident at 8 weeks after surgery.
  
  
  CONCLUSIONS
  These results exhibited that the TCP/Col composites could sufficiently maintain bone width and height for the preservation of the extraction socket with buccal dehiscence while preventing epithelial in-growth. In addition, TCP/Col in an easily handled spongeous form could provide a better intraoral manipulation capability than TCP granules alone and was considered to be suitable as a bone grafting material used for alveolar ridge preservation.
authors.affiliation: Oral Maxillofacial Surgery, Department of Oral Restitution, Division of Oral Health Science, Tokyo Medical and Dental University Graduate School, Tokyo, Japan.
authors.forename: Yukinobu
authors.initials: Y
authors.lastname: Takahashi
authors.forename: Eriko
authors.initials: E
authors.lastname: Marukawa
authors.forename: Ken
authors.initials: K
authors.lastname: Omura
mesh_terms: D000539:Alveolar Process / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D000818:Animals; D001641:Bicuspid / Q000601:surgery; D001672:Biocompatible Materials / Q000008:administration & dosage*; D001861:Bone Regeneration / Q000187:drug effects / Q000502:physiology*; D002130:Calcium Phosphates / Q000008:administration & dosage* / Q000032:analysis / Q000737:chemistry; D003094:Collagen / Q000008:administration & dosage* / Q000737:chemistry; D003238:Connective Tissue / Q000254:growth & development; D004285:Dogs; D008437:Maxilla; D014081:Tooth Extraction; D020390:Tooth Socket / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D001672:Biocompatible Materials; D002130:Calcium Phosphates; C485817:beta-tricalcium phosphate; D003094:Collagen