Geometrical instruments – Gauge – Anatomical
Reexamination Certificate
2000-07-13
2003-02-04
Gutierrez, Diego (Department: 2859)
Geometrical instruments
Gauge
Anatomical
C033S511000, C033S531000, C033S555300, C433S224000
Reexamination Certificate
active
06513254
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to devices utilized to measure the taper and diameter of conical inserts utilized in root canal procedures, and more specifically to a gauge capable of measuring and providing a specific sized gutta percha cone for use in a tooth during a root canal procedure.
2. Description of Related Art
Teeth have an outer layer of enamel surrounding the dentin. Within the dentin is a soft tissue, commonly referred to as pulp. The pulp is where the nerves, veins, arteries, and lymph vessels are located. Pulp is typically configured in a top pulp chamber which branches down to one, two and sometimes, even up to four root canals.
If the pulp is infected, the person will likely experience pain. Many times, the most logical choice of treatments is to have a root canal procedure performed. A number of different procedures are currently practiced for performing root canals. After applying a local anesthetic to numb the area of the infected tooth, a hole is drilled into the pulp chamber. The pulp chamber and root canal(s) are then cleaned of diseased pulp. Each root canal may be filed to a specific shape to allow for a secure fit with an inserted gutta percha point, or cone. Next, medication such as antibiotics may be inserted to fight bacteria. At this point, the crown of the tooth may be temporarily resealed, left open to drain, or the canals may be filled immediately depending on the particular procedure utilized.
Regardless of the particular procedure utilized, the canals are eventually filled. Typically, gutta percha in a substantially conical shape is inserted into the canal. A sealer is used with the gutta percha to assist in providing a secure fit within the tooth and preventing recontamination. The ability to accurately and consistently fit gutta percha cones into the shape of prepared root canals is critical in most obturation or root canal techniques.
There are two types of gutta percha cones available: standardized and non-standardized gutta percha cones. Standardized cones are conical in shape and extend from a small diameter tip or apex to a larger diameter base. The cones are tapered from the apex to the base at a specific taper. When a root canal has been filed with a specific file to a known shape, the endodonist, or dentist, may utilize a specific standardized shaped cone for obturating the canal.
Non-standardized cones are also tapered, but normally, not to the tolerances or degree of the standardized cones. They are marketed as fine, medium-fine, fine-medium, medium, large, extra-large, etc. The non-standardized cones are often heated and pressed into the root canal during the obturation process. Accordingly, capillaries, or other imperfections and passages, along the roots of the tooth can be filled with gutta percha.
A number of companies manufacture gutta percha cones. Some of the cones are hand rolled. Some of the cones are machine rolled. The tolerances for standardized cones under ISO standards are +/−0.05 mm which would correspond to +/−2.5 mm in a 0.02 mm taper, i.e., 0.02 mm per running millimeter of length. The tolerances for the files are held to a higher ISO standard of +/−0.02 mm. Therefore, a gutta percha cone selected from a manufacture, may not provide the fit desired by the practitioner and when placed within the canal may be short of the apex or out of the apex by up to 2.5 mm.
One gauge for gutta percha cones or points available on the market is made by a Swiss company, Maillefer. This device has a series of calibrated holes extending completely through the width of a plank member. The diameter of each hole is constant throughout the width of the gauge and is printed below each opening. Although this gauge measures diameter, it does not measure taper. Accordingly, even though the apex or base of a cone may be correctly sized, the taper may not provide the desired fit within a filed canal. For instance, if the taper is too large at a specific location along the cone, the cone may bind within the canal at that location preventing proper insertion of the cone. Additionally, if the taper is too small at a specific location along the cone, the cone may be loose within the cavity, possibly providing a location for bacteria growth.
SUMMARY OF THE INVENTION
It is an object of the present invention to provide a gauge to check the taper of a standardized gutta percha cone.
It is another object of the present invention to provide a gauge which allows a practitioner to modify a gutta percha cone by adjusting the apex point.
It is another object of the present invention to provide a gauge which checks the diameter of a standardized gutta percha cone at the apex and a plurality of locations along the length of the gutta percha cone between the apex and the base of the cone.
Yet another object of the present invention is to provide a gauge which may be utilized to check the diameter of the apex of a non-standardized gutta percha cone.
It is still a further object of the present invention to provide a gauge which assists in providing close tolerances between a gutta percha cone and a filed root canal.
Accordingly, the present invention recognizes and addresses the foregoing disadvantages, and others, of prior art construction and methods by providing a gutta percha cone gauge which measures, or checks, the diameter and taper of standardized gutta percha cones. The gauge may also be utilized to check certain diameters, such as the apex diameter, of non-standardized gutta percha cones.
The gauge includes a body with at least one measuring location. The measuring location includes a chute having first and second ends bounded by opposing angled walls. The preferred chute also includes a floor which supports a gutta percha cone during the measuring process. The first end of the chute has a larger cross section than the second end, and the second end is of a known width. The taper between the first and second end is a predetermined value. Additionally, the preferred gauge includes a plurality of measuring locations which correspond to a variety of apex diameters and/or tapers.
In order to check the specifications of a particular gutta percha cone with a gauge of the preferred embodiment, the cone is placed in the chute on the floor and pushed toward the second end of the chute. If the cone substantially touches the walls the length of the chute, then the taper over that length is correct. If the cone does not correspond with the angled walls along the taper, then the cone does not meet the tolerances of the gauge for that taper of cone. If the diameter of the apex of the cone corresponds with the diameter of the second end of the chute, then the cone was manufactured to be the correct diameter at its apex. If the cone corresponds in taper, but extends beyond the second end of the chute, the cone may be cut off with a scalpel or other sharp instrument to possibly provide an apex with the proper diameter.
REFERENCES:
patent: 363331 (1887-05-01), Hammer
patent: 1027287 (1912-05-01), Shee
patent: 1389486 (1921-08-01), Brewer
patent: 1424082 (1922-07-01), Clopton
patent: 2650435 (1953-09-01), Kidd
patent: 2677892 (1954-05-01), Schecter
patent: 3358826 (1967-12-01), Siegel
patent: 3772791 (1973-11-01), Malmin
patent: 3911587 (1975-10-01), Forrest et al.
patent: 4256457 (1981-03-01), Behring
patent: 4265619 (1981-05-01), Lucki et al.
patent: 4505675 (1985-03-01), Albert
patent: 4997368 (1991-03-01), Mayer et al.
patent: 5170570 (1992-12-01), Mays, Jr.
patent: 5685085 (1997-11-01), Bond
patent: 308651 (2000-07-01), None
Engineer-In-Training Preference Manual, 8th Edition, (p. 7-4, 7-5).
Gonzalez Madeline
Gutierrez Diego
Miller & Martin LLP
Ruderman Alan
Stark Stephen J.
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