title: Evaluation of the surface characteristics of anodic oxidized miniscrews and their impact on biomechanical stability: An experimental study in beagle dogs.
abstract: BACKGROUND
  In this study, we aimed to assess the surface characteristics and the biomechanical stability of miniscrews with an anodic oxidized surface compared with machined surface miniscrews in beagle dogs.
  
  
  METHODS
  Self-drilled, titanium-aluminum-vanadium alloy miniscrews with an anodic oxidized surface (n = 48) or a machined surface (n = 48) were placed into the mandibles of 12 beagle dogs. The surface characteristics of both types of miniscrews were analyzed before implantation with scanning electron microscopy and atomic force microscopy. Insertion torque was measured during placement of all 96 miniscrews. Half of the implants in each group (24 specimens per subgroup) received 200 to 250 g of tensile force for 3-week or 12-week loading periods. Removal torque was measured in 12 specimens of each subgroup, and bone-implant contact and bone volume were quantified in the other 12 specimens of each subgroup.
  
  
  RESULTS
  Atomic force microscopy measurements demonstrated that the anodic oxidized surface miniscrews had significantly higher roughness parameters than did the machined surface miniscrews (P < 0.001). The 2 types of miniscrews were not significantly different in insertion and removal torque values or in bone-implant contacts and bone volumes, regardless of the loading period.
  
  
  CONCLUSIONS
  Anodic oxidized miniscrews have different surface roughness profiles but no clinically significant superiority in biomechanical stability compared with machined surface miniscrews.
authors.affiliation: Fellow, Department of Orthodontics, The Institute of Cranial-Facial Deformity, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: Sung-Hwan
authors.initials: SH
authors.lastname: Choi
authors.affiliation: Private practice, Mokpo-si, South Korea.
authors.forename: Sung-Ho
authors.initials: SH
authors.lastname: Jang
authors.affiliation: Associate professor, Department of Orthodontics, The Institute of Cranial-Facial Deformity, College of Dentistry, Yonsei University, Seoul, South Korea.
authors.forename: Jung-Yul
authors.initials: JY
authors.lastname: Cha
authors.affiliation: Professor, Department of Orthodontics, The Institute of Cranial-Facial Deformity, College of Dentistry, Yonsei University, Seoul, South Korea. Electronic address: hwang@yuhs.ac.
authors.forename: Chung-Ju
authors.initials: CJ
authors.lastname: Hwang
mesh_terms: D000497:Alloys; D000818:Animals; D001696:Biomechanical Phenomena; D001863:Bone Screws; D000069343:Bone-Implant Interface / Q000033:anatomy & histology; D003722:Dental Alloys / Q000737:chemistry; D004285:Dogs; D055664:Electrochemical Techniques; D008297:Male; D008334:Mandible / Q000033:anatomy & histology; D008422:Materials Testing; D018625:Microscopy, Atomic Force; D008855:Microscopy, Electron, Scanning; D008904:Miniaturization; D009532:Nickel / Q000737:chemistry; D009929:Organ Size; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design; D009969:Orthodontic Wires; D010084:Oxidation-Reduction; D011897:Random Allocation; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D019415:Torque
chemical_list: D000497:Alloys; D003722:Dental Alloys; C040654:titanium nickelide; C031462:titanium alloy (TiAl6V4); D009532:Nickel; D014025:Titanium