title: Influence of biphasic calcium phosphate surfaces coated with Enamel Matrix Derivative on vertical bone growth in an extra-oral rabbit model.
abstract: OBJECTIVE
  The aim of this study was to investigate the ability of Enamel Matrix Derivative (EMD) on vertical bone regeneration around dental implants placed in an extra-oral rabbit model.
  
  
  METHODS
  A total of 30 Straumann BL implants were partially embedded in transverse orientation into the posterior mandibles of 15 rabbits. Macro-structuring BiPhasicCaPST (BCPT1), micro-structuring BiPhasicCaPST (BCPT2), and deproteinized bovine bone mineral (DBBM) were placed around the implant and covered with a scaffold stabilizing "umbrella." EMD was incorporated within the scaffold for test sites, but not control sites. Histological analysis was performed on retrieved specimens after 10 weeks of healing to assess new bone formation.
  
  
  RESULTS
  All treatment groups displayed new supracrestal bone formation as determined by histomorphometric measurements, with mean values of new bone height ranging between 0.62 and 1.13 mm. Histological analysis revealed a higher mean bone formation (%) around the test sites where EMD (34.7, 95%CI: 27.1-39.4) was released from the scaffold, whereas the control group without EMD release (26.4, 95%CI: 16.3-31.9) (P = 0.069). The mean fBIC (%) in the BCPT2 group increased by the addition of EMD relative to no EMD (67.2, 95%CI: 48.6-84.1) and (54.7, 95%CI: 32.3-68.9), respectively). The BCPT2/EMD and DBBM/EMD interventions showed the greatest mean bone density (BA/TA), respectively, (12.8, 95%CI: 8.9-36.5) and (11.2, 6.3-16.4) in ROI 1. Values in ROI 2 were, similarly, (24.9, 95%CI: 17.2-31.7) and (27.7, 19.2-35.3). BA/TA in ROI 2 differences between the BCPT2 groups with and without EMD was statistically significant (P = 0.026), as well as the DBBM groups with and without EMD (P = 0.038).
  
  
  CONCLUSIONS
  A layer of new bone was formed in both test and controls. The release of EMD from BCPT2 and DBBM adjacent to a bone-level implant with an SLActive surface and scaffold retention umbrella consistently regenerated the greater fBIC and bone density along the length of the implant.
authors.affiliation: Department of Oral & Maxillofacial Surgery, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China. wenboxmy@gmail.com.
authors.forename: Bo
authors.initials: B
authors.lastname: Wen
authors.affiliation: Department of Oral & Maxillofacial Surgery, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China.
authors.forename: Zhen
authors.initials: Z
authors.lastname: Li
authors.affiliation: Department of Prosthdontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China.
authors.forename: Rongrong
authors.initials: R
authors.lastname: Nie
authors.affiliation: Department of Orthodontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China.
authors.forename: Chao
authors.initials: C
authors.lastname: Liu
authors.affiliation: Department of Prosthdontics, Nanjing Stomatological Hospital, Medical School of Nanjing University, Nanjing, China.
authors.forename: Peng
authors.initials: P
authors.lastname: Zhang
authors.affiliation: Department of Periodontology, Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Bern, Switzerland.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Miron
authors.affiliation: Department of Periodontology and Implant Dentistry, College of Dentistry, New York University, New York, NY, USA.
authors.forename: Michel M
authors.initials: MM
authors.lastname: Dard
mesh_terms: D000818:Animals; D015519:Bone Density; D001861:Bone Regeneration; D018786:Bone Substitutes; D002417:Cattle; D003743:Dental Enamel; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D003764:Dental Materials; D017267:Dental Prosthesis Design; D006882:Hydroxyapatites; D008334:Mandible; D023421:Models, Animal; D016348:Osseointegration; D011817:Rabbits
chemical_list: D018786:Bone Substitutes; D015921:Dental Implants; D003764:Dental Materials; D006882:Hydroxyapatites; C074950:hydroxyapatite-beta tricalcium phosphate
keywords: biphasic calcium phosphate materials; enamel matrix derivative; scaffold retainer; vertical supracrestal bone growth