MXPA01006066A - Selective dentin caries excavator - Google Patents

Abstract

A dental bur (210) has a working surface including cutting elements (220) which deflect or abrade upon encountering material at or above the preselected hardness corresponding to the lower limit of hardness of non-carious dentin. The dental bur is constructed of metal, ceramic, or plastic.

Description

SELECTIVE EXCAVATOR OF CARIES IN DENTINA FIELD OF THE INVENTION This invention relates generally to the field of dental cutting tools, and more specifically, to a dental bur that selectively removes caked dentin without removing healthy dentin.

ANCHORS OF THE INVENTION There are many common dental instruments used to remove dentin from the teeth. However, normally, unless the operator detects when a harder material is encountered and the drilling immediately ceases, the prior art cutters will continue to cut into normal dentin during and after removal of the caged dentin. Due to the difficulty of accurately detecting when harder material is found, the side effect of using said strawberry is some normal healthy dentin cut. In addition, this produces an infected and clogged strawberry that is relatively expensive to discard and difficult to sterilize. Therefore, it is an object of the present invention to provide a dental cutting tool capable of selectively differentiating between harder material and softer material, without considering operator control.

BRIEF DESCRIPTION OF THE INVENTION The dental cutting tool (or "cutter") of the present invention has a work surface that includes cutting elements adapted to selectively cut or drill only material of hardness less than the preselected one. When material is found above the preselected level of hardness, the cutting elements are flexed, deformed or worn, thus preventing damage to the harder non-caged dentin.

BRIEF DESCRIPTION OF THE DRAWINGS The invention is better understood from the following detailed description when read in relation to the accompanying drawings, in which: Figure 1 is a side view of a dental drill formed according to a first exemplary embodiment of the present invention; Figure 1A is a sectional view, in the plane 1A-1A, of the cutter shown in Figure 1; Figure 2 is a side view of a milling cutter formed according to a second exemplary embodiment of the present invention; Figure 2A is a sectional view, in the plane 2A-2A, of the cutter shown in Figure 2; Figure 3 is a side view of a cutter formed according to a third exemplary embodiment of the present invention; Figure 4 is a side view! of a strawberry formed according to a fourth exemplary embodiment of the present invention; Figure 4A is a sectional view, in the plane 4A-4A, of the cutter shown in Figure 4; and Figure 5 is a side view of a cutter formed according to a fifth exemplary embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the figures, in which similar numbers refer to similar steps and elements, FIGS. 1 and 1A are side and sectional views, respectively, of the cutter head of a milling cutter according to the first exemplary embodiment of the cutter. present invention. As shown in Figures 1 and 1A, the cutter 210 includes cutter blades 220 interposed between the grooves 230. The cutter blades 220 are formed to cut smooth canted dentin, but will bend inwardly in the space of the grooves 230 to reaching a dentin of a specific hardness and making the strawberry 210 inoperable temporarily or permanently. Optimally, the blades 220 may include a concavity 225 for better control of flexure, deformation and / or abrasion of blades 220 upon finding a resistive force on a preselected level, characteristic of the maximum force required to cut carved dentin, without cut healthy dentin. This may vary with different individual situations, patients, or groups of patients, but generally, the lowest level of hardness for normal dentin is on the scale of about 20 to about 60 Knoop Hardness Number (KHN). A) Yes, the blades (or cutting elements in other embodiments) of the present invention, will be constructed to flex, deform or wear out upon finding matepal above a preselected hardness, preferably above 60 KHN. Skillful designers can easily design blades 220 to flex on the preselected resistive force by appropriate selection of the blade construction material 220, and the dimensions thereof, particularly the height of each blade and the variable width of each blade. Furthermore, as indicated above, the concavities 225 can be incorporated into the design of the blades 220 to optimize bending or deformation. The number of cutter blades 220 can be increased or reduced according to design parameters. Similarly, the depth of grooves 230 can be varied and the surface area of the cutter blades 220 can be increased or decreased according to specific design parameters. For example, the number of cutter blades 220 can be reduced and the grooves 230 can be deepened to increase the digging effect in soft dentin, and decrease the efficiency of the cutter blades 220 as the cutter approaches the harder material. Another important design variable, which the expert designer will optimize for ideal performance is the concavity 225, the inclination and depth of which can vary considerably. For example, an angular indentation can also perform this bending effect function (i.e., to control the level of resistance at which the cutter blade 220 will flex). Certain embodiments of the cutter blades 220 may recover their initial shape after bending back into the slots 230 and may be available to cut more shallow and smooth carved dentin. These include modalities of molded plastic, flexible and silicone rubber. The capacity of recovery allows the removal of cared dentin through multiple vertical methods. In other alternative embodiments of the cutter 210, constructed of aluminum, aluminum alloy, hard ceramic and plastic, the blades 220 will deform or abrade and will not be operable. The shape of blades 220 and grooves 230 can be better appreciated from the cross-sectional view of the cutter 210 in Figure 1A. The cutter 210 can be made by working a relatively hard metal sphere, such as one composed of aluminum or aluminum alloy. Alternatively, the blades 220 can be formed separately and secured to an underlying base. In any case, the blades 220 can be fixed through a pin to a central pin extending through the blades 220 and the core. The spike is of standard size, such as that described in Specification No. 23 of the American National Standards Institute / American Dental Association (ANSI / ADA) (dental digging burrs). The spike can be constructed of steel, aluminum or other suitable materials. Bolt-type (Class 1-angular applicator) and friction-type (Class 4-angular applicator) dowel pins may be used in the excavator of the present invention. The cutter 210 can also be injection molded from, for example, liquid silicone rubber. The color of the cutter 210 can be made unique for each size of cutter and for each level of hardness in which the cutter 210 is molded. This allows the user of the cutter 210 to quickly identify the desired size and hardness level of the cutter. required The head of the cutter may be spherical or oval in shape, having a diameter between about 0.6 mm and about 4.0 mm. In addition, the head may have alternative shapes that are compatible with the cutting elements of the present invention. The head can be made from a variety of materials, including molded plastic, optionally polymethyl methacrylate, silicone rubber, wire ball, polymer wool, aluminum or aluminum alloy, cast alloy, and ceramic.

As an alternative for the design of the blades 220 which are flexed upon finding a preselected resistance force, the cutter blades 220 can be composed of an abradable material, such as hard ceramic elements embedded in a resin base, designed to fracture or release the ceramic element when the pre-selected resistance force is found. The cutter 210 can also be worked from a hard ceramic material or injection molded from plastic material. Other features can be designed for the blades 220 by increasing or decreasing the distance between consecutive blades 220 and, thereby, lengthening or reducing the area of the slots where the blades 220 can contract. Other alternative cutter designs are shown, for example. example, in figure 2, a side view of the cutter 210 formed according to a second exemplary embodiment of the present invention, and in figure 2A, a cross section of the cutter 310 shown in figure 2. Figure 3 shows Strawberry 410 with wires 420 in a polymer wool ball. Figure 4 shows a cutter 510 in a ball-like structure and figure 4A shows a cross section of the cutter 510 shown in figure 4. Figure 5 shows a cutter 610 which also has wires 620 in an alternative structure similar to a ball. The cutters shown in Figures 2-5 all vary in their mechanical design, but each depends on the core concept of the present invention which is the use of cutting elements whether they flex, deform or wear out upon finding a force. of pre-selected cutting resistance. This force is characteristic of the differential force below which soft or canted dentine can be cut or drilled by the cutter and above which the cutting action against the healthy dentin can also be effective. These different mechanical shapes of the present invention include, in FIGS. 2 and 2A, a central member similar to a ball 300 with a threaded recess 302 for mounting the reamer on a conventional dental drilling apparatus. Although not shown in the figures, said mounting gap is necessarily included in all the milling heads made of a material other than the shank, that is, worked ceramic, molded silicone rubber, wire ball, polymer wool ball and ceramic foam versions. In addition, the mounting gap is not necessary when the material for the complete excavator (blades, core and shank) is the same, ie machined aluminum or aluminum alloy and molded plastic versions. As described above, the excavator spigot conforms to ANSI / ADA specifications. The dental burr 310 of FIGS. 2 and 2A also includes outwardly perforated projections 320 which serve as cutting elements. Like the cutting blades of the cutter 210 in FIG. 1, the external projections 320 in the cutter 310, of FIGS. 2 and 2A, are mechanically designed either to flex or wear out when finding dentin of preselected hardness. Said design can easily be made by those skilled in the art by reference to the dimensions of the material used in the construction of the vertical projections, which constitute cutting elements 320 in the cutter of Figures 2 and 2A. In addition, the modalities, as shown in figures 3 and , comprises dental burs wherein the cutting elements, which may be arranged on a mounting ball as in the above embodiments, comprise relatively hard wire-like cutting material 420, in FIG. 3, or material 320, in FIG. Figure 5. The material is strong enough to flex and abrade to cut softer dentine material, but sufficiently foldable or abradable to prevent cutting or damage of healthy dentin material. This can be useful to avoid interruption of the cutting action in other cutters in which narrow grooves in a cutter 210 of the type shown in Figure 1, or a more dense cutting material in a cutter 510 of the type shown in Figure 4, is fully loaded with carved dentin removed from the drilling surface, thus preventing a subsequent cutting action. The cutting effectiveness of the wires shown in Figures 3 and 5 will be determined by the design factors of the shape flexibility of the selected wire with respect to the cross section of the individual wire strands, and the density of the wire. This is a relation of the space occupied by the wire itself against the space occupied by the interstices surrounding the wire. The selection of material will also be an important part of the design consideration in the development of cutting elements based on wire type materials according to these modalities. Another embodiment of the present invention is that shown in Figures 4 and 4A, in which the dental drill 510 comprises a ball element with pores 520. The surrounding residual material of the pores 520 on the external surface of the ball-type drill 510 comprises cutting elements which, as in previous embodiments, are designed with respect to the construction material and the dimensions. The ball-type burr 510 further includes a recess 540 for mounting the bur 510 on a conventional dental drilling apparatus. A porous cutter 510 as shown in Figures 4 and 4A can also be specifically designed to provide sufficient porosity to retain carious dentin removed from the drilling surface in order to avoid interruption of the cutting process. Although the present invention is illustrated and described with reference to certain specific embodiments, it is not intended to be limited to the details shown. Rather, various modifications can be made to the details within the scope and scale of equivalents of the claims and without departing from the invention.

Claims (16)

NOVELTY OF THE INVENTION CLAIMS

1. - A dental drill for use in removal of dentin careada teeth, said strawberry has a work surface that includes cutting elements, said cutting elements are adapted to flex, deform or wear to find material that has a hardness in or above of a preselected hardness corresponding to the lower hardness limit of non-canted dentin.

2. The dental burr according to claim 1, further characterized in that said cutter is placed on a mounting element, adapted to be retained and activated by a dental drilling apparatus.

3. The dental burr according to claim 2, further characterized in that said mounting element is movably placed in said apparatus.

4. The dental burr according to claim 1, further characterized in that said cutting elements are flexed when they act by a shear force exceeding that necessary to cut material at or above said preselected hardness.

5. - The dental drill according to claim 3, further characterized in that said cutting elements are external projections arranged on a ball-like structure surface.

6. The dental burr according to claim 5, further characterized in that said cutting elements comprise a metal.

7. The dental burr according to claim 6, further characterized in that said metal is aluminum or aluminum alloy.

8. The dental burr according to claim 1, further characterized in that said cutting elements comprise a plurality of blades projecting outwardly interposed between a plurality of grooves without a ball-like structure.

9. The dental burr according to claim 8, further characterized in that said cutting elements comprise aluminum or aluminum alloy.

10. The dental burr according to claim 3, further characterized in that said cutting elements comprise a mass of wires formed around a ball-type structure.

11. The dental burr according to claim 3, further characterized in that said cutting elements comprise a mass of wires having a random orientation and are compacted to form a ball-like structure.

12. - The dental drill according to claim 1, further characterized in that said cutting elements wear when a shear force exceeding that necessary to cut material at or above said preselected hardness acts.

13. The dental drill according to claim 12, further characterized in that said cutting elements comprise a plurality of blades interposed between a plurality of slots in a ball-type structure.

14. The dental burr according to claim 12, further characterized in that said abradable cutting elements comprise a hard plastic or ceramic material, said abradable cutting elements embedded in a material substantially softer than said plastic or ceramic material and which can be separated from said softer material when it acts by a force on the scale necessary to cut dentine material with a hardness equal to or greater than the hardness of said uncarved dentin.

15. The dental burr according to claim 12, further characterized in that said abradable cutting elements comprise a material of plastic or hard ceramic, said abradable cutting elements being deformable when acting by a force on the scale necessary to cut material from dentin with a hardness equal to or greater than the hardness of said dentin not careada.

16. - The dental drill according to claim 1, further characterized in that said cutting elements comprise silicone rubber that projects outwardly and said cutting elements are deformed when acting by a force on the scale necessary to cut dentin material with a hardness equal to or greater than the hardness of said uncared dentine, and after deformation when said cutting elements no longer act with said force, said cutting elements are recovered to project outwards.