Biomedical subjects

J F Osier

Publications and source records attributed to J F Osier.

4 recordsLinked to original sources

PubMed1992

Early uncovering of HA-coated cylinder implants: case report of an in vivo shear strength test.

A new approach was used to test the readiness of an HA-coated implant for commencement of prosthetic procedures after two months of bone healing in humans. A torquing device was used for clinical measurement of the shear resistance of the supporting bone. It was found that the bone was capable of resisting a shear force just slightly greater than that which was necessary to produce displacement of implants placed in dog femurs with a comparable bone-healing period and with healing to full maturity. This report suggests that it may be feasible to uncover HA-coated implants after two months of bone healing.

Dental Implants↗

PubMed1992

Load transfer from endosteal implants to supporting bone: an analysis using statics. Part one: Horizontal loading.

By use of engineering statics, the amount of force transferred to the crestal bone from a horizontal occlusal load, relative to the implant length necessary to support that load, was analyzed for hypothetical instances when the implant was embedded in a uniform mass of bone and when it was bicorticated. The analysis revealed that implants longer than 12 mm will not significantly reduce force transfer proportionately to the increased length. Also, bicortication will mitigate force transfer to the crestal bone. Finally, the amount of force transfer is directly proportional to the height of load application from the crestal bone.

Alveolar Process↗

PubMed1992

Load transfer from endosteal implants to supporting bone: an analysis using statics. Part two: Axial loading.

Engineering statics was used for the analysis of axial occlusal load transfer by a dental implant to the supporting bone. The analysis revealed that an implant can be totally supported by trabecular bone. Also, an implant of only 10 mm in length with a 4-mm diameter can transmit average maximum biting forces to the supporting bone within the physiologic strain limits of the bone.

Alveolar Process↗

PubMed1991

Biomechanical load analysis of cantilevered implant systems.

Historically, dental implants have been placed in areas where quality bone exists. The maxillary sinus areas and mandibular canal proximities have been avoided. From these placements, various cantilevered prosthetic applications have emerged. This analysis uses static engineering principles to define the loads (i.e., forces) placed upon the implants. These principles make use of Newton's first and third laws of mechanics by summing the forces and moments to zero. These summations then generate mathematical equations and their algebraic solutions. Three implant systems are analyzed. The first is a two-implant system. The second is a three-implant cross-arch stabilized system usually found in mandibular replacements of lower full dentures. The third is a five-implant system which is identical to the three-implant cantilevered system but which uses implants in the first molar area, thereby negating the cantilevered load magnification of the three-implant design. These analyses demonstrate that, in a cantilevered application, the implant closest to the point of load application (usually the most posterior implant) takes the largest compressive load. Implants opposite the load application (generally the anterior implant) are in tension. These loads on the implants are normally magnified over the biting force and can easily reach 2 1/2 to five times the biting load.

Bite Force↗