Improvements relating to tools for dental work
CA 2116781 A1 · Owner: Gwilliam, Douglas George · Inventors: Gwilliam, Douglas George; Norman, David George
Overview
Its claims, description and drawings are in the Canadian Patents Database.
Open the CIPO recordAbstract From the Canadian patent
A dental tool for shaping teeth has a shank for fitting to a rotary drive and an abrasive head on the shank for working on teeth. For false teeth, the shank diameter, at least at the end that fits the drive, will be 2.35 mm, while for real teeth that diameter will be 1.6 mm. The head comprises diamond grit in a resin matrix, the resin preferably being a resole phenolic resin. Further particulate filler may be added.
Read the whole patent
Listed from its CIPO record in Patent Yard's archive of Canadian patents past their term. Its claims, description and drawings are in the CIPO record and on Google Patents, and the Claude kit works from them.
Why it's free to use
- Filed July 5, 1993. No grant is recorded for it in Canada; had it been granted, its 20-year term would have ended July 5, 2013.
- A certificate of supplementary protection adds at most two years for a drug, so even that would have ended by July 5, 2015.
- We check Canadian rights only. A patent in its family in another country could still be in force: check its family on Google Patents.
Timeline
Timeline From CIPO dates
Sources & verification
Official CIPO records
Everything on this page comes from the CIPO record linked above. Contains information licensed under the Open Government Licence – Canada.