Patent Application
20090081609
This invention relates generally to disposable prophy angles designed to be mounted on powered dental handpieces, and more particularly, to prophy angles having grips that enable the prophy angles to be comfortably grasped by the fingers and the thumb of the dental professional using it, which resist slippage, and which tactilely direct the user's fingers and thumb into the proper position to handle the prophy angle in an effective manner.
Modern dental prophylaxis includes the removal of deposits and stains from the teeth by scaling and polishing. The principal purpose of polishing the teeth is to remove plaque and stain and to make the surfaces smooth so that it is more difficult for plaque and debris to attach and accumulate. In the polishing step, typically a polishing paste is applied using a powered prophy device such as a prophy angle with an attached elastomeric prophy cup.
A conventional prophy angle is typically attached to an appropriate powered dental handpiece so that a drive gear of the dental handpiece meshes with corresponding gearing in the prophy angle to rotate an elastomeric cup mounted in the head of the device. The rotating elastomeric cup is used in tooth cleaning and polishing procedures.
Disposable prophy angles made of suitable rigid plastic materials are widely available. They are mass produced and therefore very economical.
In order to ensure optimal control of a prophy angle in the close space of a patient's mouth, it is desirable to hold the prophy angle with the thumb and fingers gripping the body of the device, rather than the handpiece to which it is mounted. Unfortunately, however, dental professionals unconsciously tend to grip the handpiece instead, foregoing the optimal hand placement. This may be due to a number of reasons, including more noticeable and uncomfortable vibration in the prophy angle than in the handpiece that drives it, slipperiness of the hard plastic surface of the prophy angle, (particularly as it accumulates moisture during use), or a lack of tactile consciousness regarding where the gripping is actually maintained while the dental prophylaxis proceeds.
Thus, a disposable prophy angle that could be comfortably grasped by the fingers and the thumb of the dental professional using it, which would resist slippage, and which would tactilely direct the user's fingers and thumb into the proper position to handle the prophy angle more effectively would constitute an important contribution to the art.
The present invention relates to a prophy angle for mounting on a powered dental handpiece with a grip of the prophy angle to be comfortably grasped by the fingers and thumb of the user. The grip not only resists slippage, it also tactilely directs the user's fingers and thumb into the proper position to handle the prophy angle in an effective manner. The prophy angle includes a head and body, the body including a neck, a shoulder and a base and a prophy cup rotatably mounted to the front of the head. An elastomeric neck portion runs along the back of the neck, an elastomeric shoulder portion runs along the back of the shoulder, and an elastomeric base portion running about the base.
The foregoing objects, advantages and features of the present invention will be apparent from the following detailed description and the accompanying drawings, in which like referenced numerals have been used to designate like or similar elements, and in which:
Turning now to the Figures, a prophy angle 10 in accordance with the present invention is shown. The prophy angle includes a head 12 and a body 14. Body 14 includes a neck 16, a shoulder 18 and a base 20. The prophy angle is molded from an appropriate rigid resin such as polypropylene, polyethylene, acetyl, acrylontrile-butadiene-styrene (ABS), or nylon. Among these, ABS is currently preferred.
An elastomeric prophy cup 22 is rotatably mounted to the front of head 12 such that the major axis of the prophy cup intersects the major axis of the head and these axes are generally perpendicular to the major axis of body 14 of the device.
Rotation of the prophy cup is achieved by a mechanism including a drive gear disposed within the head and body of the device. This drive mechanism is of conventional design and is not shown in the figures, but for a protruding portion of the drive 24 which will engage the powered dental handpiece so that the dental handpiece can rotate the drive gear to produce the desired rotation in the prophy cup.
The distal end 26 of base 20 is generally circular and dimensioned so that its inner diameter will fit snugly upon the handpiece 28 (
Prophy angle 10 includes an elastomeric overmolded area 32. Overmolded area 32 generally comprises three portions: an elastomeric neck portion 34, an elastomeric shoulder portion 36 and an elastomeric base portion 38. The elastomeric neck portion runs along the back 40 of neck 16, generally opposite the front of the head to which cup 22 is mounted. The elastomeric shoulder portion runs along the back 42 of shoulder 18, also generally opposite the front of the head to which cup 22 is mounted. Finally, the elastomeric base portion 38 extends about the circumference of the base 20 of the prophy angle. The elastomer of the base, however, stops short of the distal edge of the angle and the edge of notch 30 to establish a rigid perimeter 44 to insure that the rigid resin material of the prophy angle rather than the elastomer will engage handpiece 28. Preferably, the overmolded area will be generally continuous as illustrated in
Preferred elastomers used in elastomeric overmolded area 32 will chemically bond to the rigid base member and include urethanes, styrene-ethylene-butylene-styrene or SEBS elastomers (e.g. Kraton or Dynaflex, available from GLS Corporation of Cary, Ill., and metallocene elastomers (e.g., Engage, available from DuPont Dow Elastomers, L.L.C. of Freeport, Tex.) and fully vulcanized ethylene-propylene-diene-monomers in a continuous matrix of polypropylene (e.g., Santoprene, available from Advanced Elastomer Systems, L.P., of Akron, Ohio). Among these, Dynaflex is presently preferred. It is preferred that the elastomer have a Shore A hardness of less than about 60, and preferably a Shore A hardness in the range of about 5-45. Presently, a Shore A hardness of about 40 is most preferred.
In
Operation of the prophy angle of the present invention may be best understood by reference to
The elastomeric overmolded areas dampen the transmission of vibration from the prophy angle to the user's fingers and hand, making the device more comfortable to use than current hard plastic prophy angles. Also, in a preferred embodiment, dimples 56 will be formed in the surface of the elastomeric portions to enhance these effects. Most importantly, the disposition of the elastomeric surfaces guides the dental professional's fingers into the optimal position on the prophy angle as the differing surface textures and resilience of the elastomeric areas and the hard plastic areas are picked up tactically as the device is handled. This insures that the dental professional's fingers will be up high on the prophy angle where the greatest force and dexterity of manipulation can be maintained, to facilitate the most efficient and effective polishing and cleaning by the prophy cup.
All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.
The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.
Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. It should be understood that the illustrated embodiments are exemplary only, and should not be taken as limiting the scope of the invention.
