title: Histomorphological and torque removal comparison of 6 mm orthodontic miniscrews with and without surface treatment in New Zealand rabbits.
abstract: OBJECTIVE
  The purpose of this study was to assess the difference of removal torque values (RTV) and the bone-to-implant contact (BIC) between the sand-blasted, large grit, and acid-etched (SLA) surface-treated and the machined surface (MA) miniscrews.
  
  
  METHODS
  Miniscrews used in this study were 6mm long with a diameter of 1.5mm. A total of 23 SLA miniscrews and 24 MA miniscrews were placed into the distal femoral condyle of 24 New Zealand rabbits. Removal torque test and the BIC was histologically evaluated at 0 and 8 weeks.
  
  
  RESULTS
  There was no statistical difference between the RTV in the MA group versus the SLA group at both 0 and 8 weeks. Comparing 0-8 weeks, there was no significant difference in RTV of the SLA group (P = 0.48), however the change in the MA group was statistically significant (P = 0.006). Histological observation showed a significant decrease in BIC comparing 0 and 8 weeks for the MA group. The BIC ratio at 8 weeks was statistically significantly higher in the SLA group compared to the MA group.
  
  
  CONCLUSIONS
  SLA surface preparation does not increase the RTV of miniscrews. Further investigations under loading and a large sample size are required.
authors.affiliation: *Discipline of Orthodontics, Faculty of Dentistry and.
authors.forename: Arthessarat
authors.initials: A
authors.lastname: Sirisa-Ard
authors.affiliation: *Discipline of Orthodontics, Faculty of Dentistry and.
authors.forename: Sabrina Natalie
authors.initials: SN
authors.lastname: Woodroffe Michael
authors.affiliation: *Discipline of Orthodontics, Faculty of Dentistry and.
authors.forename: Kamal
authors.initials: K
authors.lastname: Ahmed
authors.affiliation: **Department of Biomedical Engineering, School of Aerospace, Mechanical and Mechatronic Engineering, The University of Sydney, New South Wales.
authors.forename: Colin R
authors.initials: CR
authors.lastname: Dunstan
authors.affiliation: ***Surgical Research Australia Pty Ltd, North Adelaide, South Australia, and.
authors.forename: Simon G
authors.initials: SG
authors.lastname: Pearce
authors.affiliation: ****Department of Statistics, Faculty of Science, Macquarie University, Sydney, New South Wales, Australia.
authors.forename: Ayse Aysin
authors.initials: AA
authors.lastname: Bilgin
authors.affiliation: *Discipline of Orthodontics, Faculty of Dentistry and oyku.dalci@sydney.edu.au.
authors.forename: Oyku
authors.initials: O
authors.lastname: Dalci
authors.affiliation: *Discipline of Orthodontics, Faculty of Dentistry and.
authors.forename: M Ali
authors.initials: MA
authors.lastname: Darendeliler
mesh_terms: D000134:Acid Etching, Dental / Q000379:methods; D000497:Alloys; D000818:Animals; D001863:Bone Screws; D000069343:Bone-Implant Interface / Q000033:anatomy & histology* / Q000502:physiology; D003722:Dental Alloys / Q000737:chemistry; D045662:Dental Etching / Q000379:methods; D005269:Femur / Q000033:anatomy & histology / Q000502:physiology / Q000601:surgery; D008297:Male; D008422:Materials Testing; D008904:Miniaturization; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design; D016348:Osseointegration / Q000502:physiology; D011817:Rabbits; D013499:Surface Properties; D013997:Time Factors; D014025:Titanium / Q000737:chemistry; D019415:Torque
chemical_list: D000497:Alloys; D003722:Dental Alloys; C031462:titanium alloy (TiAl6V4); D014025:Titanium