Granted Patent
Utility
US 5,085,586 · App. 07/574,214
Method and apparatus for installing a post in a tooth having an existing endodontic obturator therein
Inventor:
William B. Johnson
Patented Case
View Patent ↗
Granted: Feb 4, 1992
Filed: Aug 28, 1990
Inventor
William B. Johnson
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.