title: Primary stability and histomorphometric bone-implant contact of self-drilling and self-tapping orthodontic microimplants.
abstract: BACKGROUND
  The aim of this study was to evaluate the primary stability and the histomorphometric measurements of self-drilling and self-tapping orthodontic microimplants and the correlations between factors related to host, implant, and measuring technique.
  
  
  METHODS
  Seventy-two self-drilling and self-tapping implants were placed into bovine iliac crest blocks after computed tomography assessments. Insertion torque values, subjective assessments of stability, and Periotest (Medizintecknik Gulden, Modautal, Germany) measurements were performed for each implant. Twelve specimens of each group were assigned to histologic and histomorphometric assessments.
  
  
  RESULTS
  The differences between insertion torque values, most Periotest values, and subjective assessments of stability scores were insignificant (P >0.05). The bone-implant contact percentage of the self-drilling group (87.60%) was higher than that of the self-tapping group (80.73%) (P <0.05). Positive correlations were found between insertion torque value, cortical bone thickness, and density in both groups (P <0.05). Negative correlations between insertion torque values and Periotest values were mostly observed in the self-drilling group (P <0.05). Positive correlations were found between bone-implant contact percentages, cortical bone densities, and insertion torque values in both groups (P <0.05). The differences between insertion torque values and corresponding subjective assessments of stability scores were different in both groups (P <0.05).
  
  
  CONCLUSIONS
  The differences in insertion torque values, Periotest values, and subjective assessments of stability scores of self-drilling and self-tapping implants were insignificant. Self-drilling implants had higher bone-implant contact percentages than did self-tapping implants. Significant correlations were found between parameters influencing the primary stability of the implants.
authors.affiliation: Department of Orthodontics, Faculty of Dentistry, Başkent University, Ankara, Turkey.
authors.forename: Seçil
authors.initials: S
authors.lastname: Çehreli
authors.forename: Ayça
authors.initials: A
authors.lastname: Arman-Özçırpıcı
mesh_terms: D000818:Animals; D015519:Bone Density / Q000502:physiology; D001842:Bone and Bones / Q000473:pathology*; D002138:Calibration; D002417:Cattle; D015921:Dental Implants; D008422:Materials Testing; D052280:Orthodontic Anchorage Procedures / Q000295:instrumentation*; D016382:Orthodontic Appliance Design; D016348:Osseointegration / Q000502:physiology*; D013499:Surface Properties; D014057:Tomography, X-Ray Computed; D019415:Torque; D014732:Vibration
chemical_list: D015921:Dental Implants