title: Biomechanical evaluation of oversized drilling technique on primary implant stability measured by insertion torque and resonance frequency analysis.
abstract: BACKGROUND
  This study evaluated the influence of implant site preparation depth on primary stability measured by insertion torque and resonance frequency analysis (RFA).
  
  
  METHODS
  Thirty-two implant sites were prepared in eight veal rib blocks. Sixteen sites were prepared using the conventional drilling sequence recommended by the manufacturer to a working depth of 10mm. The remaining 16 sites were prepared using an oversize drilling technique (overpreparation) to a working depth of 12mm. Bone density was determined using cone beam computerized tomography (CBCT). The implants were placed and primary stability was measured by two methods: insertion torque (Ncm), and RFA (implant stability quotient [ISQ]).
  
  
  RESULTS
  The highest torque values were achieved by the conventional drilling technique (10mm). The ANOVA test confirmed that there was a significant correlation between torque and drilling depth (p<0.05). However, no statistically significant differences were obtained between ISQ values at 10 or 12 mm drilling depths (p>0.05) at either measurement direction (cortical and medullar). No statistical relation between torque and ISQ values was identified, or between bone density and primary stability (p >0.05).
  
  
  CONCLUSIONS
  Vertical overpreparation of the implant bed will obtain lower insertion torque values, but does not produce statistically significant differences in ISQ values.
  
  
  BACKGROUND
  Implant stability quotient, overdrilling, primary stability, resonance frequency analysis, torque.
authors.affiliation: Professor Department of Stomatology I, School of Medicine and Dentistry, University of the Basque Country, Leioa, Spain.
authors.forename: Gorka
authors.initials: G
authors.lastname: Santamaría-Arrieta
authors.affiliation: Professor Department of Surgery and medical-surgical specialties, University of Oviedo, Oviedo, Spain.
authors.forename: Aritza
authors.initials: A
authors.lastname: Brizuela-Velasco
authors.affiliation: Professor Department of Orthodontics and Dentofacial Orthopedics, University of Oviedo, Oviedo, Spain.
authors.forename: Felipe J
authors.initials: FJ
authors.lastname: Fernández-González
authors.affiliation: Professor Department of Stomatology I, School of Medicine and Dentistry, University of the Basque Country, Leioa, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Chávarri-Prado
authors.affiliation: Graduate student. Engineering Physics Department of Nuclear Engineering and Fluid Mechanics, Engineering School, University of the Basque Country, Bilbao, Spain.
authors.forename: Yelko
authors.initials: Y
authors.lastname: Chento-Valiente
authors.affiliation: Researcher. Department of Graphic Design and Engineering Projects, University of the Basque Country UPV/EHU, Bilbao, Spain.
authors.forename: Eneko
authors.initials: E
authors.lastname: Solaberrieta
authors.affiliation: Student of oral implantology degree in the University of the Basque Country, Leioa, Spain.
authors.forename: Markel
authors.initials: M
authors.lastname: Diéguez-Pereira
authors.affiliation: Professor and full chair. Department of morphology and Cell Biology, University of Oviedo, Spain; Professor. Facultad de Ciencias de la Salud, Universidad Autónoma de Chile, Chile.
authors.forename: José-Antonio
authors.initials: JA
authors.lastname: Vega
authors.affiliation: Student of oral implantology degree in the University of the Basque Country, Leioa, Spain.
authors.forename: Jaime
authors.initials: J
authors.lastname: Yurrebaso-Asúa