Abstract:
A cup for use with the handpiece of an apparatus for applying gas to a portion of a tooth comprising a liner ( 18 ) configured and arranged to engage a gas dispensing handpiece, a body ( 16 ) defining a gas exposure chamber ( 28 ), the body having a higher resiliency to deformation than the liner. The body may be so deformable that it forms against the surface of a tooth to effect a seal and to expose a portion of the tooth to gas circulated in the chamber. The body may overmold the liner and may be formed of thermal-plastic rubber, and the liner may be formed of a plastic material. The gas exposure chamber may be cylindrical.

Description:
This application claims the benefit of U.S. Provisional Application(s) No. 60/393,206 filing date Jul. 2, 2002 

   TECHNICAL FIELD 
   The present invention relates to apparatus for applying ozone in the treatment of dental caries and, more particularly, to an improved cup for the handpiece of an apparatus for treating dental caries. 
   BACKGROUND ART 
   The use of ozone in the treatment of dental caries is shown and described in U.S. patent application Ser. No. 09/712,611, which issued Sep. 24, 2002 as U.S. Pat. No. 6,454,566 entitled “Apparatus for the Treatment of Dental Caries.” U.S. Pat. No. 6,454,566 in its entirety, including the specification and drawings, is incorporated herein by reference. That patent discloses an apparatus for the treatment of dental caries which generally includes a source of oxidizing gas and a handpiece for delivering the gas to a tooth. A cup attached to the handpiece is provided for receiving the gas and exposing a selected area of the tooth to the gas. Such cup is a unitary formed member which includes a resilient edge for sealably engaging the tooth around the selected area to prevent escape of the gas therepast. All of the disclosed embodiments of the cups include cup chambers that subtend cup edges. The cups include walls that define the chamber and include first perimeters for sealably coupling the walls to the handpiece and second perimeters that provide for coupling the walls to the tooth and exposing the selected areas to gas circulated in the chambers. 
   However, it has been found that the cups taught in the prior art do not adequately provide both a secure but temporary attachment to the outlet of the handpiece as well as proper resiliency with respect to the portion of the cup applied to the tooth. Accordingly, it would be useful to provide a cup for use with the handpiece which provides the proper rigidity desired to fit tightly around the outlet of the ozone dispensing handpiece as well as the flexibility desired for the cup to form around an uneven tooth to affect a vacuum seal before the unit dispenses ozone. 
   DISCLOSURE OF THE INVENTION 
   With parenthetical reference to the corresponding parts, portions or surfaces of the disclosed embodiment, merely for the purposes of illustration and not by way of limitation, the present invention provides an improved cup ( 15 ) for use with the handpiece of an apparatus for applying ozone to the surface of a tooth. The improvement comprises a liner ( 17 ) configured and arranged to engage a gas dispensing handpiece, a body ( 16 ) defining a gas exposure chamber ( 28 ), the liner having a higher resiliency to deformation than the body. The body may be so deformable that it forms against the surface of a tooth to effect a seal and to expose a portion of the tooth to gas circulated in the chamber. The body may overmold the liner and may be formed of thermal-plastic rubber, and the liner may be formed of a plastic material. The gas exposure chamber may be cylindrical. The present invention also discloses a method for manufacturing the improved cup. 
   Accordingly, the general object of the present invention is to provide an improved cup which fits properly onto the handpiece of an ozone dispensing device. 
   Another object is to provide an improved cup which is flexible or pliable enough for the edge of the cup to form against the uneven surfaces of a tooth to affect a vacuum seal. 
   Another object is to provide an improved cup which is rigid enough to removably attach to the outlet of a handpiece. 
   Another object is to provide an improved cup which is disposable. 
   Another object is to provide an improved cup having a liner and an over molded body. 
   Another object is to provide an improved method for manufacturing a cup. 
   Another object is to provide an improved method of manufacturing a cup in which the liner is insert molded with the body being formed around it. 
   These and other objects and advantages will become apparent from the foregoing and ongoing written specification and the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a front view of the improved cup. 
       FIG. 2  is a vertical sectional view of the cup shown in  FIG. 1 , taken generally on line  2 — 2  of  FIG. 1 . 
       FIG. 3  is a plan view of the cup shown in  FIG. 1 . 
       FIG. 4  is a rotated front view of the body shown in  FIG. 1 . 
       FIG. 5  is a horizontal sectional view of the body shown in  FIG. 4 , taken generally on line  5 — 5  of  FIG. 4 . 
       FIG. 6  is a right side view of the body shown in  FIG. 5 . 
       FIG. 7  is a rotated front view of the liner shown in  FIG. 1 . 
       FIG. 8  is a horizontal sectional view of the liner shown in  FIG. 7 , taken generally on line  8 — 8  of  FIG. 7 . 
       FIG. 9  is a right side view of the liner shown in  FIG. 7 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   At the outset, it should be clearly understood that like reference numerals are intended to identify the same structural elements, portions or surfaces, consistently throughout the several drawing figures, as such elements, portions or surfaces may be further described or explained by the entire written specification, of which this detailed description is an integral part. Unless otherwise indicated, the drawings are intended to be read (e.g., cross-hatching, arrangement of parts, proportion, degree, etc.) together with the specification, and are to be considered a portion of the entire written description of this invention. As used in the following description, the terms “horizontal”, “vertical”, “left”, “right”, “up” and “down”, as well as adjectival and adverbial derivatives thereof (e.g., “horizontally”, “rightwardly”, “upwardly”, etc.), simply refer to the orientation of the illustrated structure as the particular drawing figure faces the reader. Similarly, the terms “inwardly” and “outwardly” generally refer to the orientation of a surface relative to its axis of elongation, or axis of rotation, as appropriate. 
   Referring now to the drawings and, more particularly, to  FIGS. 1 and 2  thereof, this invention provides an improved ozone applicator cup, of which the presently preferred embodiment is generally indicated at  15 . Cup  15  is shown as broadly including a body  16  and a liner  17 . Body  16  and liner  17  are generally cylindrically shaped members. 
     FIG. 4  shows body  16  of cup  15 .  FIG. 5  is a sectional view of body  16  shown in  FIG. 4 , taking generally on line  5 — 5  of  FIG. 4 . Referring to  FIG. 5 , body  16  is a specially configured member elongated along axis x—x and is bounded by a rightwardly-facing annular vertical surface  18 , a rightwardly and outwardly-facing frusto-conical surface  19 , an outwardly-facing horizontal cylindrical surface  20 , a leftwardly-facing annular vertical surface  21 , an inwardly-facing horizontal cylindrical surface  22 , a rightwardly-facing annular vertical surface  23 , an inwardly-facing horizontal cylindrical surface  24 , a leftwardly-facing annular vertical surface  25 , and an inwardly-facing horizontal cylindrical surface  26 , joined at its right marginal end to the inner marginal end of surface  18 . Surface  26  generally defines cup chamber  28 . 
     FIG. 6  shows liner  17  of cup  15 .  FIG. 8  is a sectional view of liner  17 , taken generally on line  8 — 8  of  FIG. 7 . Referring to  FIG. 8 , liner  17  is a specially-configured solid member elongated along axis x—x, and is bounded by a rightwardly-facing annular vertical surface  29 , an outwardly-facing horizontal cylindrical surface  30 , a leftwardly-facing annular vertical surface  31 , an inwardly-facing horizontal cylindrical surface  32 , a rightwardly-facing annular vertical surface  33 , an inwardly-facing horizontal cylindrical surface  34 , a leftwardly-facing annular vertical surface  35 , and an inwardly-facing horizontal cylindrical surface  36 , joined at its right marginal end to the inner marginal end of surface  29 . 
   As shown in  FIGS. 1–2 , liner  17  is encased in the bottom portion of body  16 . In particular, liner  17  fits within the recess defined by surfaces  23 ,  24  and  25  of body  16 . Thus, surface  29  of liner  17  abuts surface  25  of body  16 , surface  30  of liner  17  abuts surface  24  of body  16 , and surface  31  of liner  17  abuts surface  23  of body  16 . Thus, when fully formed, the diameter of cylindrical surface  32  and the diameter of cylindrical surface  22  are the same. Also, the diameter of cylindrical surface  36  is approximately the same as the diameter of the cylindrical surface  26 . 
   Cup  15  is manufactured using a two-part molding process in a controlled and clean environmental. The first step of the process is to form liner  17 . Liner  17  is formed by conventional injection molding. The injection mold is a 32-cavity, hot runner SPI  102  production mold. Thus, each cycle produces 32 liners and the plastic remains molten right up to injection into the part. SPI refers to the Society of Plastics Industry, Inc. classifications. A Class  102  mold generally has a cycle life of less than one million cycles and a minimum base hardness of 280 BHN. The material used to form liner  17  is a plastic material. It has a good abrasion resistance and overmold adhesion to polypropylene and good compression set. In the preferred-embodiment, it has the following characteristics: 
                                               SPECIFIC GRAVITY   0.89           ref. ASTM D792, 23/23° C.           SHORE A HARDNESS   68           ref. ASTM D2240, 10 sec.           TENSILE STRENGTH (PSI)   952           ref. ASTM D412-Die C, 2 hrs, 23° C.           ELONGATION (%)   639           ref. ASTM D412-Die C, 2 hrs, 23° C.           MODULUS @ 300% (PSI)   551           ref. ASTM D412-Die C, 2 hrs, 23° C.           VISCOSITY @ 11170/sec (Pa-sec)   6.4           200° C.                        
As a result, it will not unduly deform when fit onto the outlet of a handpiece for an ozone delivery device. The VERSALLOY XL 9070X-1 product sold by GLS Corporation, of 833 Ridgeview Dr., McHenry, Ill. 60050 may be employed in the preferred embodiment.
 
   The second step is the overmold of body  16 . Liner  17  is insert molded with body  16  being formed over it (overmolded). In the preferred embodiment, the injection mold is a 16-cavity, hot runner SPI  102  production mold with interchangeable 16-cavity sets for each of the desired sizes. A snap core pin protrudes up from the bottom of the cavity to simulate the outlet of the handpiece and has the same features as the particular handpiece with which the cup will be used. The liner is positioned on the pin and then overmolded with body  16 . Using this type of overmolding, the physical characteristics of liner  17  and body  16  can be different. Accordingly, liner  17  is designed with features, such as higher resiliency to deformation, to allow for an appropriate fit of cup  15  onto a handpiece, while body  16  is designed with features, such as higher pliability and softness, to allow for cup  15  to create a seal around a tooth surface to expose the subject area to gas circulated in chamber  28 . The material used to form overmolded body  16  is a thermoplastic rubber compound. In the preferred embodiment, it has the following characteristics: 
                                               SPECIFIC GRAVITY   0.86           ref. ASTM D792, 23/23° C.           SHORE A HARDNESS   3           ref. ASTM D2240, 10 sec.           TENSILE STRENGTH (PSI)   300           ref. ASTM D412-Die C, 2 hrs, 23° C.           ELONGATION (%)   1,516           ref. ASTM D412-Die C, 2 hrs, 23° C.           MODULUS @ 300% (PSI)   25           ref. ASTM D412-Die C, 2 hrs, 23° C.           VISCOSITY @ 11170/sec (Pa-sec)   2.3           200° C.           COLOR   Clear                        
The VERSAFLEX CL2000X compound sold by GLS Corporation, of 833 Ridgeview Dr., McHenry, Ill. 60050 may be employed in the preferred embodiment.
 
   With respect to both liner  17  and body  16 , a color concentrate may be added, with different colors identifying different part sizes. 
   The present invention contemplates that many changes and modifications may be made. For example, the particular dimensions of the preferred embodiment may be altered as may be the cross-sectional geometry. For example, body  16  and liner  17  may have an oval geometry rather than a cylindrical geometry, or surface  26  may be tapered with a leftwardly and inwardly-facing frusto-conical surface. Therefore, while the presently-preferred form of the cup has been shown and described, and several modifications thereof discussed, persons skilled in this art will readily appreciate that various additional changes and modifications made be made without departing from the spirit of the invention.