title: Effect of strain at low-frequency loading on peri-implant bone (re)modelling: a guinea-pig experimental study.
abstract: OBJECTIVE
  To investigate whether controlled early loading enhances peri-implant bone mass and bone-to-implant contact. Low-frequency stimulation (3 Hz) and varying force amplitudes, causing varying strains, were applied in three guinea-pig series.
  
  
  METHODS
  Three series of guinea-pigs received percutaneous TiO(2)-blasted implants in both tibiae. One week after implant installation, one implant was stimulated with a sinusoidally varying bending moment while the contra-lateral implant served as an unloaded control. Force amplitudes of 0.5, 1 and 2 N were applied on a 20-mm-long cantilever, resulting in strains of 133, 267 and 533 muepsilon, respectively, measured by a strain gauge bonded on the surface of the tibial bone at 1.3 mm from the implant's distal surface. Implant stability was followed by means of resonance frequency analysis. Bone-to-implant contact and bone mass [BM (%) bone occupied area fraction] were analysed histomorphometrically.
  
  
  RESULTS
  A significant positive effect on the difference in bone mass at the stimulated vs. at the control side was observed in the distal half peri-implant marrow cavity for early mechanical stimulation at a frequency of 3 Hz (P<0.0001). An optimum was reached for the applied load, which causes a strain of approximately 267 muepsilon 1.3 mm from the implant. Implant stability gradually increased in time; no significant effect of early stimulation could be measured.
  
  
  CONCLUSIONS
  The effect of early controlled mechanical stimulation on the peri-implant bone, in this cortical bone model, is strongly dependent on force amplitude/strain at low-frequency stimulation.
authors.affiliation: Department of Prosthetic Dentistry/BIOMAT Research Group, School of Dentistry, Oral Pathology and Maxillofacial Surgery, Faculty of Medicine, K.U.Leuven, Leuven, Belgium.
authors.forename: Els
authors.initials: E
authors.lastname: De Smet
authors.forename: Siegfried V N
authors.initials: SV
authors.lastname: Jaecques
authors.forename: John J
authors.initials: JJ
authors.lastname: Jansen
authors.forename: Frank
authors.initials: F
authors.lastname: Walboomers
authors.forename: Jos
authors.initials: J
authors.lastname: Vander Sloten
authors.forename: Ignace E
authors.initials: IE
authors.lastname: Naert
mesh_terms: D000818:Animals; D001696:Biomechanical Phenomena; D016723:Bone Remodeling / Q000502:physiology*; D003758:Dental Implantation, Endosseous / Q000379:methods*; D015921:Dental Implants; D003799:Dental Stress Analysis; D006168:Guinea Pigs; D008297:Male; D016348:Osseointegration / Q000502:physiology*; D013977:Tibia / Q000601:surgery; D016474:Weight-Bearing
chemical_list: D015921:Dental Implants