title: Biomechanical evaluation of oversized drilling on implant stability - an experimental study in sheep.
abstract: OBJECTIVE
  To evaluate the effect of oversized drilling on implant success and secondary stability.
  
  
  METHODS
  The experimental study was conducted in Turkey from January to July 2013, after approval by the ethics committee of the University of Ankara, and comprised 2 female sheep. Alumina blasted implants 4mm in diameter and 10mm in length were employed; 16 implant sites were prepared on the proximal tibias of the 2 sheep. In the right tibia, a standard preparation with 3.5mm diameter was performed in the control group, while in the left tibia, an over-preparation with 4.2mm diameter was performed at the experimental group. The implants of the control group were non-mobile, while the experimental group had rotational and vertical movements. The initial implant stability was measured using the resonance frequence analysis. Animals were sacrificed after 12 weeks, and resonance frequence analysis and reverse torque values were measured.
  
  
  RESULTS
  In the experimental group, the mean resonance frequence analysis value was 60.25±7.46 (range: 49-74) at the end of the 12-week healing period. There was no statistically significant difference between the two groups (p=0.926). In the removing stage, the mean reverse torque values was 97.75±22.23N/cm (range: 68.63-138.83) for control group and 96.25±21.93N/cm (range: 63.34-126.9) for the experimental group (p=0.84).
  
  
  CONCLUSIONS
  Osseointegration can be achieved in the absence of primer stability in the 12-week period of healing time even for alumina-blasted implants.
authors.affiliation: Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Ankara University, Ankara, Turkey.
authors.forename: Mehmet Emre
authors.initials: ME
authors.lastname: Yurttutan
authors.affiliation: Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Ankara University, Ankara, Turkey.
authors.forename: Recep
authors.initials: R
authors.lastname: Kestane
authors.affiliation: Faculty of Dentistry, Department of Oral and Maxillofacial Surgery, Ankara University, Ankara, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Keskin
authors.affiliation: Faculty of Dentistry, Department of Oral and Maxillofacial Surgery Osmangazi University, Eskisehir, Turkey.
authors.forename: Omur
authors.initials: O
authors.lastname: Dereci
mesh_terms: D000818:Animals; D003758:Dental Implantation, Endosseous / Q000009:adverse effects / Q000379:methods; D015921:Dental Implants / Q000009:adverse effects*; D003781:Denture Retention / Q000379:methods; D004195:Disease Models, Animal; D005260:Female; D006801:Humans; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D008953:Models, Anatomic; D016348:Osseointegration / Q000502:physiology; D011183:Postoperative Complications / Q000175:diagnosis / Q000209:etiology; D012756:Sheep; D013977:Tibia / Q000601:surgery
chemical_list: D015921:Dental Implants
keywords: Animal study, Dental implant, Implant stability, Osseointegration, Oversized drilling.