title: Laser-treated stainless steel mini-screw implants: 3D surface roughness, bone-implant contact, and fracture resistance analysis.
abstract: OBJECTIVE
  This study investigated the biomechanical properties and bone-implant intersurface response of machined and laser surface-treated stainless steel (SS) mini-screw implants (MSIs).
  
  
  METHODS
  Forty-eight 1.3mm in diameter and 6mm long SS MSIs were divided into two groups. The control (machined surface) group received no surface treatment; the laser-treated group received Nd-YAG laser surface treatment. Half in each group was used for examining surface roughness (Sa and Sq), surface texture, and facture resistance. The remaining MSIs were placed in the maxilla of six skeletally mature male beagle dogs in a randomized split-mouth design. A pair with the same surface treatment was placed on the same side and immediately loaded with 200 g nickel-titanium coil springs for 8 weeks. After killing, the bone-implant contact (BIC) for each MSI was calculated using micro computed tomography. Analysis of variance model and two-sample t test were used for statistical analysis with a significance level of P <0.05.
  
  
  RESULTS
  The mean values of Sa and Sq were significantly higher in the laser-treated group compared with the machined group (P <0.05). There were no significant differences in fracture resistance and BIC between the two groups.
  
  
  CONCLUSIONS
  animal study
  
  
  CONCLUSIONS
  Laser treatment increased surface roughness without compromising fracture resistance. Despite increasing surface roughness, laser treatment did not improve BIC. Overall, it appears that medical grade SS has the potential to be substituted for titanium alloy MSIs.
authors.affiliation: Department of Orthodontics, University of Detroit Mercy School of Dentistry, MI, Department of Orthodontics and Oral Facial Genetics.
authors.forename: He-Kyong
authors.initials: HK
authors.lastname: Kang
authors.affiliation: Department of Restorative Dentistry, Division of Dental Biomaterials, Indiana University School of Dentistry, Indiana University-Purdue University, Indianapolis, IN.
authors.forename: Tien-Min
authors.initials: TM
authors.lastname: Chu
authors.affiliation: Department of Biomedical Sciences, Baylor College of Dentistry, Texas A&M Health Science Center, Dallas, TX.
authors.forename: Paul
authors.initials: P
authors.lastname: Dechow
authors.affiliation: Department of Orthodontics and Oral Facial Genetics, Indiana University School of Dentistry, Indiana University-Purdue University, Indianapolis, IN, USA, and.
authors.forename: Kelton
authors.initials: K
authors.lastname: Stewart
authors.affiliation: Department of Orthodontics, School of Dentistry, Kyung-Pook National University, Daegu, Korea.
authors.forename: Hee-Moon
authors.initials: HM
authors.lastname: Kyung
authors.affiliation: Department of Orthodontics and Oral Facial Genetics, Indiana University School of Dentistry, Indiana University-Purdue University, Indianapolis, IN, USA, and ssliu@iu.edu.
authors.forename: Sean Shih-Yao
authors.initials: SS
authors.lastname: Liu
mesh_terms: D000818:Animals; D001863:Bone Screws; D000069343:Bone-Implant Interface / Q000033:anatomy & histology* / Q000000981:diagnostic imaging; D003722:Dental Alloys / Q000737:chemistry / Q000528:radiation effects*; D045662:Dental Etching / Q000295:instrumentation / Q000379:methods*; D004285:Dogs; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D053844:Lasers, Solid-State; D008297:Male; D008437:Maxilla / Q000601:surgery; D009532:Nickel / Q000737:chemistry; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D009969:Orthodontic Wires; D011897:Random Allocation; D013193:Stainless Steel / Q000737:chemistry / Q000528:radiation effects*; D013314:Stress, Mechanical; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry; D019415:Torque; D055114:X-Ray Microtomography
chemical_list: D003722:Dental Alloys; C040654:titanium nickelide; D013193:Stainless Steel; D009532:Nickel; D014025:Titanium