title: Correlation between Initial BIC and the Insertion Torque/Depth Integral Recorded with an Instantaneous Torque-Measuring Implant Motor: An in vivo Study.
abstract: BACKGROUND
  Quantitative intraoperative evaluation of bone quality at implant placement site and postinsertion implant primary stability assessment are two key parameters to perform implant-supported rehabilitation properly. A novel micromotor has been recently introduced allowing to measure bone density at implant placement site and to record implant insertion-related parameters, such as the instantaneous, average and peak insertion torque values, and the insertion torque/depth integral.
  
  
  OBJECTIVE
  The aim of this study was to investigate in vivo if any correlation existed between initial bone-to-implant contact (BIC) and bone density and integral values recorded with the instrument.
  
  
  METHODS
  Twenty-five patients seeking for implant-supported rehabilitation of edentulous areas were consecutively treated. Before implant placement, bone density at the insertion site was measured. For each patient, an undersized 3.3 × 8-mm implant was placed, recording the insertion torque/depth integral values. After 15 minutes, the undersized implant was retrieved with a 0.5 mm-thick layer of bone surrounding it. Standard implants were consequently placed. Retrieved implants were analyzed for initial BIC quantification after fixation, dehydration, acrylic resin embedment, sections cutting and grinding, and toluidine-blue and acid fuchsine staining. Correlation between initial BIC values, bone density at the insertion site, and the torque/depth integral values was investigated by linear regression analysis.
  
  
  RESULTS
  A significant linear correlation was found to exist between initial BIC and (a) bone density at the insertion site (R = 0.96, explained variance R(2)  = 0.92) and (b) torque/depth integral at placement (R = 0.81, explained variance R(2)  = 0.66).
  
  
  CONCLUSIONS
  The system provided quantitative, reliable data correlating significantly with immediate postinsertion initial BIC, and could therefore represent a valuable tool both for clinical research and for the oral implantologist in his/her daily clinical practice.
authors: Dental School, Vita-Salute University and IRCCS San Raffaele, Milan, Italy.
authors: Paolo
authors: P
authors: Capparé
authors: Dental School, Vita-Salute University and IRCCS San Raffaele, Milan, Italy.
authors: Raffaele
authors: R
authors: Vinci
authors: Dental School, Vita-Salute University and IRCCS San Raffaele, Milan, Italy.
authors: Danilo Alessio
authors: DA
authors: Di Stefano
authors: Dental School, Vita-Salute University and IRCCS San Raffaele, Milan, Italy.
authors: Tonino
authors: T
authors: Traini
authors: Faculty of Psychology, Vita-Salute San Raffaele University, Milan, Italy.
authors: Giuseppe
authors: G
authors: Pantaleo
authors: Dental School, Vita-Salute University and IRCCS San Raffaele, Milan, Italy.
authors: Enrico Felice
authors: EF
authors: Gherlone
authors: Dental School, University of Brescia, Brescia, Italy.
authors: Giorgio
authors: G
authors: Gastaldi
mesh_terms: D000328:Adult; D000368:Aged; D000539:Alveolar Process / Q000473:pathology / Q000601:surgery*; D015519:Bone Density; D000069343:Bone-Implant Interface / Q000601:surgery*; D003758:Dental Implantation, Endosseous; D015921:Dental Implants; D003799:Dental Stress Analysis / Q000379:methods*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D019415:Torque
chemical_list: D015921:Dental Implants
keywords: bone density; bone to implant contact; dental implant; histomorphometry; implant stability; insertion torque; primary stability