title: Biomechanical comparison of different surface modifications for dental implants.
abstract: OBJECTIVE
  A satisfactory clinical outcome in dental implant treatment relies on primary stability for immediate load bearing. While the geometric design of an implant contributes to mechanical stability, the nature of the implant surface itself is also critically important. Biomechanical and microcomputerized tomographic evaluation of implant osseointegration was performed to compare alternative structural, chemical and biochemical, and/or pharmaceutical surface treatments applied to an identical established implant design.
  
  
  METHODS
  Dental implants with the same geometry but with 6 different surface treatments were tested in vivo in a sheep model (pelvis). Peri-implant bone density and removal torque were compared at 2, 4, and 8 weeks after implantation. Implant surfaces tested were: sandblasted and acid-etched titanium (Ti), sandblasted and etched zirconia, Ti coated with calcium phosphate (CaP), Ti modified via anodic plasma-chemical treatment (APC), bisphosphonate-coated Ti (Ti + Bisphos), and Ti coated with collagen containing chondroitin sulfate (CS).
  
  
  RESULTS
  All dental implants were well integrated at the time of sacrifice. There were no significant differences observed in peri-implant bone density between implant groups. After 8 weeks of healing, removal torque values for Ti, Ti + CaP, Ti + Bisphos, and Ti + collagen + CS were significantly higher than those for zirconia and Ti + APC.
  
  
  CONCLUSIONS
  Whereas the sandblasted/acid-etched Ti implant can still be considered the reference standard surface for dental implants, functional surface modifications such as bisphosphonate or collagen coating seem to enhance early peri-implant bone formation and should be studied further.
authors.affiliation: Institute for Surgical Technology and Biomechanics, University of Bern, Switzerland. stephen.ferguson@artorg.unibe.ch
authors.forename: Stephen J
authors.initials: SJ
authors.lastname: Ferguson
authors.forename: Jens D
authors.initials: JD
authors.lastname: Langhoff
authors.forename: Katrin
authors.initials: K
authors.lastname: Voelter
authors.forename: Brigitte
authors.initials: B
authors.lastname: von Rechenberg
authors.forename: Dieter
authors.initials: D
authors.lastname: Scharnweber
authors.forename: Susanne
authors.initials: S
authors.lastname: Bierbaum
authors.forename: Matthias
authors.initials: M
authors.lastname: Schnabelrauch
authors.forename: Armin R
authors.initials: AR
authors.lastname: Kautz
authors.forename: Vinzenz M
authors.initials: VM
authors.lastname: Frauchiger
authors.forename: Thomas L
authors.initials: TL
authors.lastname: Mueller
authors.forename: G Harry
authors.initials: GH
authors.lastname: van Lenthe
authors.forename: Falko
authors.initials: F
authors.lastname: Schlottig
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000818:Animals; D001696:Biomechanical Phenomena; D015519:Bone Density / Q000502:physiology; D050071:Bone Density Conservation Agents / Q000737:chemistry; D002130:Calcium Phosphates / Q000737:chemistry; D002809:Chondroitin Sulfates / Q000737:chemistry; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003094:Collagen / Q000737:chemistry; D045662:Dental Etching / Q000379:methods; D015921:Dental Implants; D003764:Dental Materials / Q000737:chemistry; D017267:Dental Prosthesis Design; D017268:Dental Prosthesis Retention; D004164:Diphosphonates / Q000737:chemistry; D055664:Electrochemical Techniques; D007085:Ilium / Q000601:surgery; D008422:Materials Testing; D016348:Osseointegration / Q000502:physiology; D010012:Osteogenesis / Q000502:physiology; D011897:Random Allocation; D012756:Sheep; D013314:Stress, Mechanical; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry; D019415:Torque; D055114:X-Ray Microtomography; D015040:Zirconium / Q000737:chemistry
chemical_list: D050071:Bone Density Conservation Agents; D002130:Calcium Phosphates; D020099:Coated Materials, Biocompatible; D015921:Dental Implants; D003764:Dental Materials; D004164:Diphosphonates; D002809:Chondroitin Sulfates; D003094:Collagen; C020243:calcium phosphate; D015040:Zirconium; D014025:Titanium; C028541:zirconium oxide