Patent Abstract:
An artificial tooth system, including a denture-engaging body portion, a first recess formed in the denture-engaging body portion, and a pivot base positioned within the first recess and operationally connected to the denture-engaging body portion. A generally spherical ball connector extends from the pivot base. A pivot platform is pivotably connected to the generally spherical ball portion and a resilient ring is positioned around the generally spherical ball connector and situated between the pivot base and the pivot platform. A membrane is sealingly connected around the pivot base and the pivot platform. The tooth also includes a crown portion with a second recess formed in the crown portion, wherein the pivot platform is positioned within the second recess.

Full Description:
TECHNICAL FIELD 
     The novel technology relates generally to the field of dentistry, and, more particularly, to an artificial tooth having a dynamic crown portion. 
     BACKGROUND 
     A natural tooth flexes by moving within the periodontal tissue surrounding the root such that the tooth&#39;s effective flexural center is relatively low, which is important in biting, chewing and mastication. In contrast, artificial teeth are rigid, and denture wearers often experience discomfort when biting and chewing food. In particular, denture wearers are prone to soreness in their lower gums because they have to apply excess pressure when they chew. The excess pressure is required because since the dentures are rigid, with the teeth rigidly attached thereto, it s difficult for the wearer to feel small jaw movements, in particular side-to-side and forward-to-backward movement of the upper and lower jaws against each other, that are basic to chewing. Without this sensory feedback, the denture wearer has to apply excess pressure to accomplish chewing. This excess pressure and associated friction, is transmitted directly through the rigid dentures and into the wearer&#39;s gums, making them tender and sore. Accordingly, it is desirable to have an artificial tooth that mimics the flexion of a natural tooth. Thus, there is a need for an artificial tooth that can automatically flex like a natural tooth during mastication. The present novel technology arises from an attempt to address this need. 
     SUMMARY 
     The present novel technology relates to an artificial tooth having built in flexibility. One object of the present novel technology is to provide an improved artificial tooth. Related objects and advantages of the present novel technology will be apparent from the following description. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of an artificial tooth according to one embodiment of the present novel technology. 
         FIG. 2  is an exploded cross-sectional view of the tooth of  FIG. 1 . 
         FIG. 3  is an exploded cross-sectional view of the pivot assembly of  FIG. 2 . 
         FIG. 4  is an enlarged cross sectional view of the pivot assembly of  FIG. 3 . 
     
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     For the purposes of promoting an understanding of the principles of the novel technology and presenting its currently understood best mode of operation, reference will now be made to the embodiments illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the novel technology is thereby intended, with such alterations and further modifications in the illustrated device and such further applications of the principles of the novel technology as illustrated therein being contemplated as would normally occur to one skilled in the art to which the novel technology relates. 
       FIGS. 1-4  illustrate one embodiment of the present novel technology, an artificial tooth  2  having a crown portion  4 , a membrane portion  18  and a denture-engaging or body portion  6 . The crown portion  4  defines the working surface of the tooth  2  that directly engages food during chewing. The denture-engaging portion  6  in part mimics the function of a natural tooth&#39;s root. The membrane  18  is typically a generally fluid-impervious seal, and is more typically sealingly connected between the crown portion  4  and the denture-engaging portion  6  to define an integral tooth  2 . 
     The crown portion  4  is typically connected to a female connector  10 , and more typically the crown portion  4  includes a recess  8  formed therein for receivably connecting with the female connector  10 , although the crown portion  4  may remain unrecessed and connected to the female connector  10 , such as through a generally planar crown connection interface. Likewise, the body portion  6  is connected to a male connector  14 , and more typically includes a recess  20  for receivably connecting to the male connector  14 . Of course, the crown portion  4  may be connected to the male connector  14  and the body portion  6  may be connected to the female connector  10 . 
     The crown portion  4  is pivotably connected to the body portion  6  through the pivot assembly  28 . The pivot assembly is typically a ball-and-socket connector, wherein the ball  16  of the male connector  14  is matable with the socket  26  of the female connector  10 . The pivot assembly  28  provides vertical integrity to the tooth  2 . The pivot assembly  28  may optionally include an O-ring  12  disposed between the female connector  10  and the male connector  14 . 
     The male and female connectors  14 ,  10  are preferably made of medical grade steel, ceramic composite material, or the like. The male and female connectors  14 ,  10  are typically precision machined such that the male connector  14  may be mated readily and securely with the female connector  10 , to promote a generally frictionless, yet snug, connection so as to impart vertical integrity to the tooth  2 . The male and female connectors  14 ,  10  are mated by snapping the male ball  16  into the female socket  26 . The ball  16  typically defines a diameter slightly greater than the opening of the socket  26 . The O-ring  12  is typically positioned around the ball  16  before the ball  16  is snapped into the socket  26 . 
     The O-ring  12  operates to both assist in the assembly of the pivot assembly  28 , and thus the tooth  2 , by maintaining the female connector  10  in static relation to the male connector  14  during incorporation of the membrane  18 . The O-ring  12  likewise assists with the support of the mated male connector  14  and the female connector  10 , as well as to help maintain the connectors  10 ,  14  in an uncompressed static relationship with each other  10 ,  14 . In other words, the O-ring  12  both supports the crown portion  4  when not engaged in chewing, and also dampens the motion of the crown portion  4  while chewing. 
     During mastication of a food bolus, the socket  26  pivots about the ball  16 , providing a deflective force to the food bolus. The application of the deflective force both aids in chewing and protects the gums from the transmission of excess forces through the tooth  2 . The O-ring  12  operates to limit the angel of deflection of the crown portion  4  during mastication. When the female connector  10  has been deflected to a position define a deflected connector  30  (as seen in  FIG. 4 ), the O-ring  12  undergoes compression to define a partially compressed O-ring  32  to mitigate deflection of the crown portion  4  and dampen the deflection forces. Upon release of the mastication forces, the O-ring  12  returns to its uncompressed dimensions, exerting a counter force on the pivot assembly  28  and thus the crown portion  4 . 
     The O-ring  12  is typically made of medical grade silicone or rubber. The O-ring typically has an outside diameter of between about 1 millimeter and about 6 millimeters, and a side diameter of between about 0.5 millimeters and about 5 millimeters, with a cross-section of between about 0.25 millimeters and about 1 millimeter. 
     The tooth  2  allows slight movement when subjected to typical mastication forces, whereby the crown portion  4  articulates independently of the body portion  6 , mimicking the movement of a natural tooth and reducing the pressure transmitted to the gums through the tooth  2 . The deflection of the crown portion thus both mitigates soreness of the gums and assists in chewing food, much in the same manner of a natural tooth. 
     The crown  4  is typically prepared by forming a recess  8  therein to receive the female connector  10 . Likewise, the body  6  is prepared by forming a recess  20  therein to receive the male connector  14 . The female connector  10  is placed within the recess  8  and secured therein by any convenient means, such as with dental cement or the like. The male connector is likewise placed in the recess  20  and similarly secured therein. Alternately, the crown and body portions  4 ,  6  may be connected to the respective connectors  10 ,  14  by any convenient means without the necessity of a recess  8 ,  20 . 
     The female connector  10  is typically of a diameter from about 3 millimeters to about 9 millimeters. The male connector  14  is typically of a diameter similar to, or slightly less than, the female connector  10 , more typically from about 1 millimeter to about 7 millimeters. 
     The tooth  2 , with the crown and body portions matedly connected through the pivot assembly  28 , is typically sealed with the annular membrane  18 . The membrane  18  is typically positioned to surround and enclose the pivot assembly  28  and acts to seal the crown and body portions  4 ,  6  together to define the tooth  2 . The membrane  18  simulates the mechanical properties of a periodontal ligament extending between a natural tooth and a natural gum. 
     The membrane  18  may be formed from any suitable material, typically selected from materials approved for use in dental devices. The membrane  18  is typically puncture resistant, resistant or impervious to fluids and foodstuffs, and erosion resistant. The membrane  18  typically has an outside diameter from about ½ a millimeter to about 6 millimeters, and a cross sectional thickness from about 1 millimeter to about 2 millimeters. 
     The membrane  18  typically surrounds the pivot assembly  28  and forms a seal between the crown portion  4  and the body portion  6 . The membrane  18  generally prevents penetration of fluids and foodstuffs from the oral cavity and surrounding environment from penetrating the tooth  2 . Further, the membrane  18  is typically resilient and may fluctuate between a normal resting state and a compressed state when mastication forces are applied. During a mastication event, the membrane  18  may also serve to limit the angle of deflection of the pivot assembly  28 /crown portion  4  relative to the body portion  6 . Upon relaxation of the mastication forces, the membrane  18  returns to its uncompressed, relaxed state and the pivot assembly  28 /crown portion  4  then is urged back towards its no normal resting state. 
     In operation, tooth  2  is inserted and secured into a denture recess  22  formed in a denture base  24 , typically by means of common dental construction procedures. The denture base  24  may then be inserted into the oral cavity and held in place by any convenient denture adhesive. During chewing, the pivot assembly  28  allows the crown portion  4  to deflect about a (typically vertical) axis and thus aids the user in mastication of a food bolus by adding frictional and planar shearing forces to the crushing forces generated by the jaws, more closely mimicking mastication with a natural tooth. The O-ring  12  and the membrane  18  both assist in the return of the pivot assembly  28  (and thus the crown portion  4 ) to its normal resting orientation when no mastication forces are applied to urge the crown portion away therefrom. 
     Generally, the pivot assembly  28  provides a higher flexion point within the tooth  2 . The higher flexion point enables the user to provide less chewing pressure to achieve deflection of the crown portion  4  to mimic the behavior of a natural tooth. 
     While the novel technology has been illustrated and described in detail in the drawings and foregoing description, the same is to be considered as illustrative and not restrictive in character. It is understood that the embodiments have been shown and described in the foregoing specification in satisfaction of the best mode and enablement requirements. It is understood that one of ordinary skill in the art could readily make a nigh-infinite number of insubstantial changes and modifications to the above-described embodiments and that it would be impractical to attempt to describe all such embodiment variations in the present specification. Accordingly, it is understood that all changes and modifications that come within the spirit of the novel technology are desired to be protected.

Technology Classification (CPC): 0