Patents by Inventor Peter J. Renkema

Peter J. Renkema has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5702677
    Abstract: A process for producing spherical, non-porous hydroxyapatite particles having a size which does not exceed 250 microns and having a density of at least 3.00 g/cc. The process comprises agglomerating in the presence of water as the only additive hydoxyapatite powder feedstock having a purity of at least 97%, and having metallic impurities which do not exceed 500 ppm, to form hydroxyapatite particles having a size which does not exceed 350 microns. The particles are then dried and then sintered at a temperature from about 1,100.degree. C. to about 1,200.degree. C. to provide spherical, non-porous hydoxyapatite particles which do not exceed 250 microns and having a density of at least 3.00 g/cc. Such particles have a variety of medical uses, including bone replacement, implant coatings, and dental applications such as alveolar ridge augmentation, root extraction site fillings, restoration of periodontal osseous lesions, and soft tissue augmentations.
    Type: Grant
    Filed: July 10, 1996
    Date of Patent: December 30, 1997
    Assignee: Osteotech, Inc.
    Inventors: Lawrence A. Shimp, Peter J. Renkema