title: Biological effects of compressive forces exerted on particulate bone grafts during socket preservation: animal study.
abstract: OBJECTIVE
  To compare different compressive forces exerted on a particulate graft material during socket preservation and their effects on bone regeneration.
  
  
  METHODS
  Six male dogs were used. The second, third, and fourth premolars, and the first molar were extracted bilaterally at the lower jaws. A particulate synthetic biphasic grafting material (60% HA and 40% β-tricalcium phosphate) was used. Three different standardized compressive forces were applied randomly during the socket preservation. The sample was divided into four experimental groups Test A (10 g), Test B (50 g), Test C (200 g), and Control (empty sockets). Collagen membranes were placed, and primary closure was obtained. Two months after the surgery the animals were sacrificed, and histomorphometric analysis of non-decalcified samples was performed at the coronal, middle, and apical thirds.
  
  
  RESULTS
  Grafted sockets resulted in higher bony contour (3 ± 0.43 mm2; P < 0.05). The particles penetrated up to the apical third in the group C but not in the other test groups and controls (P < 0.05). The percentage of new bone were higher at the coronal and apical thirds for Controls and group C compared to A and B groups (P < 0.05). The residual graft was higher for group C (53 ± 1.4%), followed by group B (45 ± 3.1%) and group A (35 ± 1.9%; P < 0.05). The percentages of connective tissue were higher at the middle third without differences between groups (P > 0.05).
  
  
  CONCLUSIONS
  Within the limitations of this experimental animal study, it might be concluded that grafted sockets compressed with 200 g force will have higher bony contours; higher compressive forces facilitate the penetration of the particulate graft material into the apical area of the socket and results in more bone formation at the coronal, middle, and apical thirds.
authors.affiliation: Department of Prosthodontics and Digital Technology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA.
authors.forename: Rafael
authors.initials: R
authors.lastname: Delgado-Ruiz
authors.affiliation: Department of Periodontology, School of Dental Medicine, Stony Brook University, Stony Brook, NY, USA.
authors.forename: Georgios E
authors.initials: GE
authors.lastname: Romanos
authors.affiliation: Department of Research, Biotecnos, Santa Maria, RS, Brazil.
authors.forename: Sergio
authors.initials: S
authors.lastname: Alexandre Gerhke
authors.affiliation: Department of Periodontics, Granada University, Granada, Spain.
authors.forename: Gerardo
authors.initials: G
authors.lastname: Gomez-Moreno
authors.affiliation: International Dentistry Research Cathedra, Universidad Católica San Antonio de Murcia (UCAM), Murcia, Spain.
authors.forename: José Eduardo
authors.initials: JE
authors.lastname: Maté-Sánchez de Val
authors.affiliation: International Dentistry Research Cathedra, Universidad Católica San Antonio de Murcia (UCAM), Murcia, Spain.
authors.forename: José Luis
authors.initials: JL
authors.lastname: Calvo-Guirado
mesh_terms: D000818:Animals; D016025:Bone Transplantation; D019245:Compressive Strength; D004285:Dogs; D008297:Male; D008334:Mandible / Q000473:pathology / Q000601:surgery*; D008963:Molar / Q000601:surgery; D010012:Osteogenesis; D020390:Tooth Socket / Q000601:surgery*
keywords: bone grafting; compression; particulate grafts; socket preservation