title: Alveolar ridge preservation prior to implant placement with surgical-grade calcium sulfate and platelet-rich plasma: a pilot study in a canine model.
abstract: OBJECTIVE
  To evaluate the combination of surgical-grade calcium sulfate (SGCS) and platelet-rich plasma (PRP) for alveolar ridge preservation prior to implant placement.
  
  
  METHODS
  Five mongrel dogs were used as subjects. Four enlarged mandibular extraction sockets, 2 on each side, were created in each dog. According to a split-mouth design, the 2 anterior sockets received either SGCS/PRP (SGCS/PRPant) or were left unfilled, while the 2 posterior sockets received either SGCS/PRP (SGCS/PRPpost) or SGCS. Computerized tomographic (CT) scans were conducted at 1 day and 8 weeks postextraction to detect the change in ridge height. Bone scintigraphy was performed at 2, 4, and 6 weeks to investigate new bone formation activity. At 8 weeks, 1 dog was sacrificed for histologic and histomorphometric study. Meanwhile, implants were placed in the remaining 4 dogs. These 4 dogs were sacrificed after 3 months.
  
  
  RESULTS
  Less ridge resorption was observed in the anterior SGCS/PRP-filled sites compared to unfilled sites (P = .001), while no significant difference was found between the SGCS/PRPpost and SGCS groups (P = .544). Bone scintigraphy showed that sites filled with SGCS/PRP showed significantly higher count/pixel at 2 (P = .028), 4 (P = .009), and 6 weeks (P = .037) than the unfilled sites. Nevertheless, the SGCS/PRPpost group achieved significantly higher values than the SGSC group only at 2 weeks (P = .036). Histomorphometrically, the SGCS/PRPant group showed a significantly higher percentage of bone-implant contact than the unfilled group (P = .024), but no significant difference was detected between the SGCS/PRPpost and SGCS groups (P = .979).
  
  
  CONCLUSIONS
  Grafting SGCS/PRP in fresh extraction sockets reduced alveolar ridge resorption and promoted the bone formation in this canine model. The addition of PRP to SGCS resulted in the enhancement of bone regeneration in the early phase of healing.
authors.affiliation: Key Laboratory of Oral Biomedical Engineering of Ministry of Education, School of Stomatology, Wuhan University, Wuhan City, People's Republic of China
authors.forename: Bin
authors.initials: B
authors.lastname: Shi
authors.forename: Yi
authors.initials: Y
authors.lastname: Zhou
authors.forename: Yi Ning
authors.initials: YN
authors.lastname: Wang
authors.forename: Xiang Rong
authors.initials: XR
authors.lastname: Cheng
mesh_terms: D016301:Alveolar Bone Loss / Q000517:prevention & control; D000539:Alveolar Process / Q000473:pathology / Q000601:surgery*; D000818:Animals; D001861:Bone Regeneration / Q000502:physiology; D001862:Bone Resorption / Q000517:prevention & control; D018786:Bone Substitutes / Q000627:therapeutic use*; D002133:Calcium Sulfate / Q000627:therapeutic use*; D015921:Dental Implants; D004285:Dogs; D008334:Mandible / Q000473:pathology / Q000601:surgery*; D023421:Models, Animal; D016348:Osseointegration / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology; D010865:Pilot Projects; D053657:Platelet-Rich Plasma; D019275:Radiopharmaceuticals; D013669:Technetium Tc 99m Medronate; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D014081:Tooth Extraction; D020390:Tooth Socket / Q000473:pathology / Q000601:surgery
chemical_list: D018786:Bone Substitutes; D015921:Dental Implants; D019275:Radiopharmaceuticals; D002133:Calcium Sulfate; D013669:Technetium Tc 99m Medronate