Abstract:
A dental mirror having a planar surface encircled by a beveled perimeter. The mirror rotatively mounted upon a spherical support ball, whereby the dentist can continually maintain the correct angle of incidence to capture and reflect light beams from a light source. The planar surface continually being capable of pivoting in relationship to the pressure by the dentist to provide the smallest angle of incidence of reflecting light beams, which is vital to securing the greatest amount of illumination to the surgical area and also in avoiding unwanted distortion of any images in the work area.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application is based on Provisional Patent Application Serial No. 60/262,679 filed Jan. 22, 2001. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a dental mirror device that is designed to more efficiently deflect light to the surgical field during dental procedures and more specifically to a dental mirror that can be angulated by the dentist, assistant or dental hygienist, to aid in indirect vision as well as the deflection of the light beam and the retraction of tissues. The three primary functions of the dental mirror will be indirect vision, deflection of light and the retraction of tissues. 
     2. Description of the Prior Art 
     The oral cavity is an extremely difficult area in which to work. Vision and access are impaired by the lips, cheek, tongue, and the patient&#39;s ability to open the mouth. Restorative care must be accomplished with extreme care as to not injure the soft tissue structures. To achieve this, retraction of such tissues will be necessary. The devices that are available and which can be used by the dental team are the dental mirror, rubber dam, cotton holders, retraction, suction lines and bite blocks. The dental mirror is the most frequently used of the above devices. When the dental mirror is being used for retraction by the assistant or dentist, the dentist is usually using direct vision. This is the actual viewing of the surgical field utilizing the dental unit light as well as the operatory ceiling light. The combination of these light beams is sufficient for operating purposes as well as to hopefully preventing eye damage, strain and fatigue. 
     The dental mirror takes on its most important functions when we use it in combinations of the illumination of the surgical field as well as indirect vision. Indirect vision is the viewing of the surgical field through the mirror image of the field. Different from the direct vision system is that in the indirect, both the operatory light as well as the dental unit light are hopefully being captured by the dental mirror such that it may be angulated or deflected to illuminate the surgical field. While this is being achieved, the dentist or hygienist are positioning the mirror to have proper visual image of the site through the mirror. 
     In the prior art the dentist accomplishes the above by a fixed handle connection to a pre-set 30° to 40° angle circular mirror head. The present invention is designed to provide increased angular capabilities for: better mirror image; to provide a more abundant and useful deflected beam of light to the field; and to place less strain and fatigue on the dentist/hygienist hands, finger, neck and back. The present invention also takes into account weight distribution, autoclavability, disposability, cost factor, handling ability and its relational benefits to better vision and better field of illumination. 
     The prior art in U.S. Pat. No. 5,458,486 issued to Ballard on Oct. 17, 1995, shows a mirror apparatus that teaches the need for adjusting the position of the mirror relative to the working area. This inventor discusses methods of bending, twisting and flexing the handle and shaft while also using a ball bearing design to not only affix the mirror to the shaft but to provide a greater range of self-adjustment for mirror angulation. Other prior art patents attempt to solve the problem of directing light beams to the work area is a similar fashion by focusing upon the articulation of the handle and shaft. 
     None of the above inventions and Patents, taken either singly or in combination, is given to describe the instant invention as claimed. 
     SUMMARY OF THE INVENTION 
     Accordingly, the above problems and difficulties are obviated by the present invention which provides for a dental mirror device which is positionable within a patient&#39;s mouth by a dentist. The apparatus includes a handle portion, a shank portion and a mirror housing. The mirror housing is attached to the shank in such a way that it is capable of being angulated to capture specular reflection and also to direct the reflected beams towards the surgical field. The angulation also aids in image reflection. It is preferred that the mirror surface be planar (flat) to insure that the image is the same size as the object. In dental procedures, it is critical that the image reflected be the same size, in order that the dentist may see the situation the way it is. 
     The present invention provides the dentist with the ability to control the angulation of the mirror so that the angle of incidence is equal to the angle of reflection. The light beam is reflected when it hits the surface of the mirror. The angle in which the beam strikes the surface is the angle with which it is reflected back. The incident ray/beam approaches the mirror with as small an angle as possible, thereby giving the sharpest possible reflective angle. This is the most desired illumination of the surgical field. 
     The present invention can utilize a variety of handles whether they be conventionally shaped, ergonomically designed, diposable, metal, or plastic. The handle may be reusable and the mirror disposable. The key is that the mirror have the ability to angulate so that the smallest angle of incidence is provided, regardless of whether the mirror is being used in a retractory fashion. 
     One object of the invention is that the mirror have the ability wherein the planar surface of the mirror will have 360 degrees of rotation and the ability to be angulated at any degree. 
     Another object of the present invention is that the mirror portion of the device be easily installed to the shank portion of the device, and easily removed for disposal or autoclaving. 
     A still further object of the present invention is that the mirror portion provides for a pre-set desired angular deviation, thereby preventing displacement of the mirror while in use. 
     Another object of the present invention is to allow the control of the angle of incidence or at least restrict it to a maximum deviation. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a view partly in elevation and partly in section illustrating the whole structure of the planar mirror. 
     FIG. 2 is an expanded view of the side of the planar mirror portion and base section of shank portion. 
     FIG. 3 is an elevational view showing a partially cross section portion of an alternate embodiment having a fixed angular deviation. 
     FIG. 4 is an elevational sectional view of an alternate embodiment of the planar mirror wherein the outer area of the mirror is angled. 
     FIG. 5 is an alternative embodient depicting by an elevational sectional view a mirror configuration having a means for limiting the angular deflection. 
     FIG. 6 is an elevational view of FIG. 5 with the addition of a circular ring for snap-fitting the mirror within a 360° area. 
     FIG. 7 is an elevational view of an alternative embodiment having a recessed groove in the base section. 
     FIG. 8 is an elevational view showing the mirror portion locked into the groove of FIG.  7 . 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     For the purposes of promoting an understanding of the principles of the invention, reference will now be made to the embodiments illustrated in the drawings and specific language that will be used to describe the same. It will never the less be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated device, and such further application of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. 
     Referring to FIGS. 1-2, a dental mirror device  20  is illustrated which can be placed in a patient&#39;s mouth. The device  20  includes a handle portion  21 , a shank portion  22 , and a mirror housing  23 . Handle portion  21  can take many forms and shapes from angulated to ergonomic without deviating from the inventive concept. For the present purposes the handle portion  21  is shown as a conventional dental mirror handle. The dentist or hygienist may manually angulate the handle to a workable position in the patient&#39;s mouth such that the incident (ray/beam) approaches the mirror with as small an angle as possible, thereby giving a reflective angle equal in degrees to the angle of incidence for the best illumination of the work area as well as the proper mirror image of the object or surgical site. 
     The prior art teaches of handles that connect to the shanks in a variety of ways. Some are screwed together or have some other manner of connecting to each other. Others are all one piece. Some are made from metals that can be autoclaved while others are made from disposable plastics. In most cases, it is the mirror housing that is the most difficult to sterilize, therefore it is often disposable. The present invention can utilize numerous configurations, however the inventive concept involves the manner in which the mirror portion  23  relates to the distal end  24  of the shank portion  22 , which has disposed therein a generally circular base section  25 . A spherically shaped ball  26  can then be screwed into the base section  25 , or be fabricated as a molded piece. Base section  25  creates a 360° constriction with the bottom section  27  of mirror housing  23 . Mirror housing  23  being of a generally circular shape, having a generally spherical shaped recess  28  in bottom support section  27 . Recess  28  being of sufficient size and shape to accept ball  26 , thereby releasably connecting mirror housing  23  to shank portion  22 . To aid in the mating process of ball  26  to recess  28 , ball  26  has a split center construction creating a pair of resilient semi-spheres with a crevice  29  defined between them. When ball  26  is inserted into recess  28  the semi-spheres are compressed together and when seated within recess  28  biasly spring apart to create a tight friction fit therein. Mirror housing  23  now being easily removed for autoclaving or disposal. Mirror housing  23  having a top support section  30  comprising of a generally circular reflective planar mirror  31  made of glass, although highly polished metal can also be used to reflect light. When mirror housing  23  is in position, the planar (flat) mirror  31  can be angulated in 360° and can only be restricted by contact between the inner edge  34  of the recess  28  and the circular restriction area  32 . It is highly desirable for the mirror surface  31  to be planar so that specular reflection is captured and the image is the same size as the object. Also, to avoid the distortion that occurs with the use of mirrors that are concave or convex. As previously stated the most useful reflective light is that which occurs at the smallest angle of incidence. The external perimeter of the top section  30  has a circular external bevel area  33  which holds the planar mirror surface  31 . With the mirror  31  rotating upon ball  26  for a full 360°, the dentist will be able to better direct the reflective light beams to the smallest angle of incidence. If desired to reduce weight at the distal end of the device, the mirror portion can have an internal void  35  between top and bottom sections  30  and  27 . 
     The present invention can be modified slightly as shown in FIG. 3 to provide an alternative embodiment  40  which would provide a raised circular ring  41  about the support base  25  to limit the angular deviation to a more precise displacement of mirror housing  23 . This alternative embodiment  40  employs a support base  41  having the same spherical ball  26  design as in the preferred embodiment  20  and the same design features at the top section  30  of the mirror housing  23  with the exception of the bottom section  27  of mirror portion  23 . A circular channel  42  is defined in the bottom section  27 . The channel of size and shape to receive the raised ring  41  in a friction-fit. Upon the mirror housing  23  rotating about the ball  26 , the ring  41  will serve to restrict the amount of tilt and the mating of ring  41  and channel  42  will serve to secure the same. 
     A modification to the planar mirror surface  31  is shown in FIG. 4, wherein the perimeter has an outer angular mirror  43  added to the inside of the perimeter. The outer perimeter  33  still being beveled to confine the mirror  31  from being dislodged. The angle of the outer mirror  43  being minimal as the slight elevation is necessary to capture more light for illumination of the working field as well as the general area. If the angle of the outer mirror  43  is too great then a large portion of light beams will be prevented from ever reaching the mirrored surface  31 . 
     Another modification is depicted by FIGS. 5 and 6. FIG. 5 shows a limited angle of deflection mirror  50  which utilizes a base  51  having a rounded convex shape defined to limit the angle of deflection of the mirror housing  23 . In this modification the bottom section  27  of the housing  23  has a concave surface  52 , which will contact the convex base  51  to thereby restrict the tilt of the mirror housing  23 . This modified mirror  50  can be further modified with a circular male positive ridge  53  disposed on the apex of the base  51  which will friction fit with a circular female negative slot  54  to lock the mirror housing  23  at a particular angulation. 
     FIGS. 7 and 8 show another modification to the basic preferred embodiment  20 . A controlled angle lock is created, not with the base section  25 , but by locking into the circular restriction area  32 . A recessed groove  55  is defined in the stem of the restriction area  32 . The inner edge  34  of the recess  28  has a generally rounded projection  56  which will lock into the recessed groove  55  at the maximum point of mirror deflection. The groove  55  being 360° allows for the mirror housing  23  to spin completely about the ball  26  at this maintained angle. The locking in of the mirror housing  23  in this fashion also prevents it from being inadvertently dislodged. 
     While there has been described what are presently considered the preferred embodiments of the invention, it will be apparent to those skilled in the art that modifications and changes can be made therein without departing from the scope of the present invention as defined by the appended claims.