The influence of static and dynamic loading on marginal bone reactions around osseointegrated implants: an animal experimental study.

Although it is generally accepted that adverse forces can impair osseointegration, the mechanism of this complication is unknown. In this study, static and dynamic loads were applied on 10 mm long implants (Brånemark System, Nobel Biocare, Sweden) installed bicortically in rabbit tibiae to investigate the bone response. Each of 10 adult New Zealand black rabbits had one statically loaded implant (with a transverse force of 29.4 N applied on a distance of 1.5 mm from the top of the implant, resulting in a bending moment of 4.4 Ncm), one dynamically loaded implant (with a transverse force of 14.7 N applied on a distance of 50 mm from the top of the implant, resulting in a bending moment of 73.5 Ncm, 2.520 cycles in total, applied with a frequency of 1 Hz), and one unloaded control implant. The loading was performed during 14 days. A numerical model was used as a guideline for the applied dynamic load. Histomorphometrical quantifications of the bone to metal contact area and bone density lateral to the implant were performed on undecalcified and toluidine blue stained sections. The histological picture was similar for statically loaded and control implants. Dense cortical lamellar bone was present around the marginal and apical part of the latter implants with no signs of bone loss. Crater-shaped bone defects and Howship's lacunae were explicit signs of bone resorption in the marginal bone area around the dynamically loaded implants. Despite those bone defects, bone islands were present in contact with the implant surface in this marginal area. This resulted in no significantly lower bone-to-implant contact around the dynamically loaded implants in comparison with the statically loaded and the control implants. However, when comparing the amount of bone in the immediate surroundings of the marginal part of the implants, significantly (P < 0.007) less bone volume (density) was present around the dynamically loaded in comparison with the statically loaded and the control implants. This study shows that excessive dynamic loads cause crater-like bone defects lateral to osseointegrated implants.

[1]  Morgan Mj,et al.  Fractures of the fixture component of an osseointegrated implant. , 1993 .

[2]  F. Isidor,et al.  Histological evaluation of peri-implant bone at implants subjected to occlusal overload or plaque accumulation. , 1997, Clinical oral implants research.

[3]  G Van der Perre,et al.  The influence of bone mechanical properties and implant fixation upon bone loading around oral implants. , 1998, Clinical oral implants research.

[4]  P. Millstein,et al.  A comparison of the accuracy of two removable die systems with intact working casts. , 1993, The International journal of prosthodontics.

[5]  F. Isidor,et al.  Loss of osseointegration caused by occlusal load of oral implants. A clinical and radiographic study in monkeys. , 1996, Clinical oral implants research.

[6]  The response of bone to external loading regimens. , 1994, Medical engineering & physics.

[7]  L Sennerby,et al.  Structure of the bone-titanium interface in retrieved clinical oral implants. , 1991, Clinical oral implants research.

[8]  J. Chow,et al.  Stimulation of bone formation by dynamic mechanical loading of rat caudal vertebrae is not suppressed by 3-amino-1-hydroxypropylidene-1-bisphosphonate (AHPrBP). , 1995, Bone.

[9]  L. Jorneus,et al.  The wide fixture: a solution for special bone situations and a rescue for the compromised implant. Part 1. , 1993, The International journal of oral & maxillofacial implants.

[10]  A. Wennerberg,et al.  Complications in partially edentulous implant patients: a 5-year retrospective follow-up study of 133 patients supplied with unilateral maxillary prostheses. , 1999, Clinical implant dentistry and related research.

[11]  T Albrektsson,et al.  A multicenter report on osseointegrated oral implants. , 1988, The Journal of prosthetic dentistry.

[12]  T Jemt,et al.  Measurements of bone and frame-work deformations induced by misfit of implant superstructures. A pilot study in rabbits. , 1998, Clinical oral implants research.

[13]  R. Kohal,et al.  Changes in peri-implant tissues subjected to orthodontic forces and ligature breakdown in monkeys. , 1998, Journal of periodontology.

[14]  J I Nicholls,et al.  Tolerance measurements of various implant components. , 1997, The International journal of oral & maxillofacial implants.

[15]  A B Carr,et al.  Full-arch implant framework casting accuracy: preliminary in vitro observation for in vivo testing. , 1993, Journal of prosthodontics : official journal of the American College of Prosthodontists.

[16]  K. Tan The clinical significance of distortion in implant prosthodontics: is there such a thing as passive fit? , 1995, Annals of the Academy of Medicine, Singapore.

[17]  H. Takahashi,et al.  A Morphometric Comparison of Trabecular Structure of Human Ilium Between Microcomputed Tomography and Conventional Histomorphometry , 1997, Calcified Tissue International.

[18]  T Jemt,et al.  Loads and designs of screw joints for single crowns supported by osseointegrated implants. , 1992, The International journal of oral & maxillofacial implants.

[19]  T Albrektsson,et al.  Experimental study of turned and grit-blasted screw-shaped implants with special emphasis on effects of blasting material and surface topography. , 1996, Biomaterials.

[20]  T Jemt,et al.  A prospective 15-year follow-up study of mandibular fixed prostheses supported by osseointegrated implants. Clinical results and marginal bone loss. , 1996, Clinical oral implants research.

[21]  M Evans,et al.  Induction of bone formation in rat tail vertebrae by mechanical loading. , 1993, Bone and mineral.

[22]  C Bessing,et al.  Loose gold screws frequently occur in full-arch fixed prostheses supported by osseointegrated implants after 5 years. , 1994, The International journal of oral & maxillofacial implants.

[23]  G C Michaels,et al.  Effect of prosthetic superstructure accuracy on the osteointegrated implant bone interface. , 1997, Oral surgery, oral medicine, oral pathology, oral radiology, and endodontics.

[24]  J Chen,et al.  Mechanical response to functional loading around the threads of retromolar endosseous implants utilized for orthodontic anchorage: coordinated histomorphometric and finite element analysis. , 1999, The International journal of oral & maxillofacial implants.

[25]  D van Steenberghe,et al.  Fixture design and overload influence marginal bone loss and fixture success in the Brånemark system. , 1992, Clinical oral implants research.

[26]  Nilgün Akin-Nergiza,et al.  Reactions of peri-implant tissues to continuous loading of osseointegrated implants. , 1998 .

[27]  A B Carr,et al.  The response of bone in primates around unloaded dental implants supporting prostheses with different levels of fit. , 1996, The Journal of prosthetic dentistry.

[28]  T Jemt,et al.  Prosthesis misfit and marginal bone loss in edentulous implant patients. , 1996, The International journal of oral & maxillofacial implants.

[29]  P I Brånemark,et al.  A 15-year study of osseointegrated implants in the treatment of the edentulous jaw. , 1981, International journal of oral surgery.

[30]  D B Burr,et al.  Increased intracortical remodeling following fatigue damage. , 1993, Bone.

[31]  Y Zilberman,et al.  Osseous adaptation to continuous loading of rigid endosseous implants. , 1984, American journal of orthodontics.

[32]  I Naert,et al.  The relationship of some histologic parameters, radiographic evaluations, and Periotest measurements of oral implants: an experimental animal study. , 1997, The International Journal of Oral and Maxillofacial Implants.

[33]  K. Balto,et al.  Quantification of Periapical Bone Destruction in Mice by Micro-computed Tomography , 2000, Journal of dental research.

[34]  J Vander Sloten,et al.  Three-dimensional force measurements on oral implants: a methodological study. , 2000, Journal of oral rehabilitation.

[35]  W C Van Buskirk,et al.  A continuous wave technique for the measurement of the elastic properties of cortical bone. , 1984, Journal of biomechanics.

[36]  J. Brunski,et al.  Effects of fabrication, finishing, and polishing procedures on preload in prostheses using conventional "gold' and plastic cylinders. , 1996, The International journal of oral & maxillofacial implants.

[37]  P. Rüegsegger,et al.  Morphometric analysis of human bone biopsies: a quantitative structural comparison of histological sections and micro-computed tomography. , 1998, Bone.

[38]  E. Radin,et al.  Bone remodeling in response to in vivo fatigue microdamage. , 1985, Journal of biomechanics.

[39]  J. Hirsch,et al.  Biological factors contributing to failures of osseointegrated oral implants. (II). Etiopathogenesis. , 1998, European journal of oral sciences.