Endodontic instruments with pilot tips and parabolic cutting flutes
AssigneeOrmco Corporation
InventorL. Stephen Buchanan
Life of this patent
Estimating the term…
Abstract
A series of multi-tapered parabolic implements is disclosed for endodontic use. The instruments comprise different sections: a pilot tip, a first portion adjacent the pilot tip and a second portion adjacent the shank. The two portions have different tapers. The tapers of the two different portions blend into each other along a parabola-shaped surface. The pilot tip is radiussed for ease of entry into a root canal with increased safety.
Claims15
An access bur for use in cutting a tapered access port into a root canal system of a tooth in apical and lateral directions, said bur comprising:
- a round shank having a first diameter;
- a non-cutting pilot tip at an end of the bur remote from said shank, said pilot tip having a second diameter which is smaller than said first diameter;
- and
- a tapered tip portion extending between said pilot tip and said shank comprising a first section (α) adjacent the pilot tip and a second section (β) adjacent the shank, each of the first section and the second section having a defined length and a cutting surface, said pilot tip having an end remote from the first section, said tapered tip portion having at least one material cutting portion comprising flutes and/or an abrasive surface throughout the defined lengths of the tapered tip portion, said tapered tip portion sized to provide said tapered access port into said root canal system;
- wherein said first section of said tapered portion has a continuously varying taper from said pilot tip adjacent said first section to said second section adjacent the shank;
- wherein the pilot tip extends forwardly from the first section for entering an upper opening in the root canal system as the bur shapes the opening by cutting the tapered access port into the canal system in the tooth;
- and
- wherein the bur is rigid, and is shaped, sized, and made of a material such that the bur is configured to rotate between 5,000-20,000 revolutions per minute to cut through the tooth and form the tapered access port.
A set of access burs for use in preparing a tapered access port into a root canal system comprising a plurality of access burs, each bur in said set of burs having differing profiles or dimensions and defined lengths from other burs in the set, comprising:
- a round shank having a first diameter;
- a pilot tip at an end of the bur remote from said shank, said pilot tip having a second diameter which is smaller than said first diameter;
- and
- a tapered tip portion extending between said pilot tip and said shank comprising a first section (α) adjacent the pilot tip and a second section (β) adjacent the shank, said tapered portion having at least one material cutting portion comprising flutes and/or an abrasive surface throughout the defined lengths of the tapered tip portion;
- wherein said first section (α) of said tapered portion has a continuously varying taper from said pilot tip adjacent the first section to said second section adjacent the shank;
- wherein the pilot tip of the bur extends forwardly from the first section, said first section shaping the tapered access port into the root canal system;
- and
- wherein the bur is rigid, and is shaped, sized, and made of a material such that the bur is configured to rotate between 5,000-20,000 revolutions per minute to cut through the tooth and form the tapered access port.
Dependencies are inferred from the claim text.