title: Efficacy of using PDGF and xenograft with or without collagen membrane for bone regeneration around immediate implants with induced dehiscence-type defects: a microcomputed tomographic study in dogs.
abstract: BACKGROUND
  Use of collagen membrane (CM) with xenograft and recombinant human platelet-derived growth factor (rhPDGF) in guided bone regeneration (GBR) is debatable. The aim of this microcomputed tomographic experiment was to assess the efficacy of using PDGF and xenograft (with or without CM) for GBR around immediate implants with dehiscence defects.
  
  
  METHODS
  Ten beagle dogs underwent atraumatic bilateral second and fourth premolar extractions from both arches. A standardized dehiscence defect (6 × 3 mm) was created on the buccal bone and immediate implants were placed in distal sockets in each site. Animals were randomly divided into three groups: 1) group 1, xenograft with rhPDGF was placed and covered with CM; 2) group 2, xenograft with rhPDGF was placed over the defects; and 3) group 3, four immediate implants were associated with dehiscence (controls). After 16 weeks, animals were sacrificed and jaw segments were assessed for buccal bone thickness (BBT), buccal bone volume (BBV), vertical bone height (VBH), and bone-to-implant contact (BIC) using microcomputed tomography.
  
  
  RESULTS
  BBT was higher in group 2 (1.533 ± 0.89 mm) than group 1 (0.745 ± 0.322 mm) (P <0.001) and group 3 (0.257 ± 0.232 mm) (P <0.05). BBV was higher in group 2 (67.87 ± 19.83 mm(3)) than group 1 (42.47 ± 6.78 mm(3)) (P <0.05) and group 3 (19.12 ± 4.06 mm(3)) (P <0.001). VBH was higher in group 2 (6.36 ± 1.37 mm) than group 3 (0.00 ± 0.00 mm) (P <0.001). VBH was higher in group 1 (3.91 ± 2.68 mm) than group 3 (0.00 ± 0.00 mm) (P <0.05). BIC was higher in group 2 (67.25% ± 13.42%) than group 1 (36.25% ± 12.78%) (P <0.05) and group 3 (30.25% ± 7.27%) (P <0.01).
  
  
  CONCLUSIONS
  GBR around immediate implants with dehiscence defects using PDGF and xenograft alone resulted in higher BBT, BBV, VBH, and BIC than when performed in combination with CM.
authors.affiliation: College of Dentistry & Applied Biomedical Sciences, King Saud University, Riyadh, Saudi Arabia.
authors.forename: Bann Ahmad
authors.initials: BA
authors.lastname: Al-Hazmi
authors.forename: Khalid Saleh
authors.initials: KS
authors.lastname: Al-Hamdan
authors.forename: Abdulaziz
authors.initials: A
authors.lastname: Al-Rasheed
authors.forename: Nadir
authors.initials: N
authors.lastname: Babay
authors.forename: Hom-Lay
authors.initials: HL
authors.lastname: Wang
authors.forename: Khalid
authors.initials: K
authors.lastname: Al-Hezaimi
mesh_terms: D000539:Alveolar Process / Q000000981:diagnostic imaging / Q000601:surgery*; D000818:Animals; D001861:Bone Regeneration / Q000187:drug effects*; D016025:Bone Transplantation / Q000379:methods*; D003094:Collagen; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D004285:Dogs; D005260:Female; D016557:Guided Tissue Regeneration, Periodontal / Q000379:methods*; D020007:Implants, Experimental; D008566:Membranes; D016348:Osseointegration; D010982:Platelet-Derived Growth Factor / Q000494:pharmacology*; D011897:Random Allocation; D011994:Recombinant Proteins / Q000494:pharmacology; D013529:Surgical Wound Dehiscence / Q000000981:diagnostic imaging / Q000601:surgery*; D020390:Tooth Socket / Q000601:surgery; D014183:Transplantation, Heterologous; D055114:X-Ray Microtomography
chemical_list: D015921:Dental Implants; D010982:Platelet-Derived Growth Factor; D011994:Recombinant Proteins; D003094:Collagen