title: Effects of pilot holes on longitudinal miniscrew stability and bony adaptation.
abstract: BACKGROUND
  The purposes of this study were to longitudinally evaluate the effects of pilot holes on miniscrew implant (MSI) stability and to determine whether the effects can be attributed to the quality or the quantity of bone surrounding the MSI.
  
  
  METHODS
  Using a randomized split-mouth design in 6 skeletally mature female foxhound-mix dogs, 17 MSIs (1.6 mm outer diameter) placed with pilot holes (1.1 mm) were compared with 17 identical MSIs placed without pilot holes. Implant stability quotient measurements of MSI stability were taken weekly for 7 weeks. Using microcomputed tomography with an isotropic resolution of 6 μm, bone volume fractions were measured for 3 layers of bone (6-24, 24-42, and 42-60 μm) surrounding the MSIs.
  
  
  RESULTS
  At placement, the MSIs with pilot holes showed significantly (P <0.05) higher implant stability quotient values than did the MSIs placed without pilot holes (48.3 vs 47.5). Over time, the implant stability quotient values decreased significantly more for the MSIs placed with pilot holes than for those placed without pilot holes. After 7 weeks, the most coronal aspect of the 6- to 24-μm layer of cortical bone and the most coronal aspects of all 3 layers of trabecular bone showed significantly larger bone volume fractions for the MSIs placed without pilot holes than for those placed with pilot holes.
  
  
  CONCLUSIONS
  MSIs placed with pilot holes show greater primary stability, but greater decreases in stability over time, due primarily to having less trabecular bone surrounding them.
authors.affiliation: Private practice, Dallas, Tex.
authors.forename: Lauren Ohlenforst
authors.initials: LO
authors.lastname: Carney
authors.affiliation: Associate professor and chairman, Department of Orthodontics, Texas A&M University Baylor College of Dentistry, Dallas, Tex.
authors.forename: Phillip M
authors.initials: PM
authors.lastname: Campbell
authors.affiliation: Associate professor, Department of Biomedical Sciences, Texas A&M University Baylor College of Dentistry, Dallas, Tex.
authors.forename: Robert
authors.initials: R
authors.lastname: Spears
authors.affiliation: Professor, Department of Orthodontics, Texas A&M University Baylor College of Dentistry, Dallas, Tex.
authors.forename: Richard F
authors.initials: RF
authors.lastname: Ceen
authors.affiliation: Research scientist, Instituo Americano de Pesquisa e Ensino Odontologico, Curitiba, Paraná, Brazil.
authors.forename: Ana Cláudia
authors.initials: AC
authors.lastname: Melo
authors.affiliation: Professor and director of Orthodontic Research, Department of Orthodontics, Texas A&M University Baylor College of Dentistry, Dallas, Tex. Electronic address: phbuschang@bcd.tamhsc.edu.
authors.forename: Peter H
authors.initials: PH
authors.lastname: Buschang
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology; D016723:Bone Remodeling / Q000502:physiology; D001863:Bone Screws; D015921:Dental Implants; D004285:Dogs; D005260:Female; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods; D008334:Mandible / Q000473:pathology / Q000601:surgery*; D008904:Miniaturization; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016348:Osseointegration / Q000502:physiology; D011897:Random Allocation; D013997:Time Factors; D014732:Vibration; D014945:Wound Healing / Q000502:physiology; D055114:X-Ray Microtomography / Q000379:methods
chemical_list: D015921:Dental Implants