Abstract:
The present invention relates to the affixation of dental dams and Class III matrixes utilized in conservative dentistry and oral surgery. In particular, the present invention relates to a device and method for retaining and stabilizing a dental dam or Class III matrix, or other device, in the mouth of the patient, which can be clamped between two adjacent teeth.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS  
       [0001]     This application is a continuation of pending U.S. patent application Ser. No. 11/013,615, filed Dec. 16, 2004 (pending), the disclosure of which is hereby incorporated by reference herein. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to the affixation of dental dams and Class III matrixes utilized in conservative dentistry and oral surgery. In particular, the present invention relates to a device and method for retaining and stabilizing a dental dam or Class III matrix, or other device, in the mouth of a patient, which can be clamped between 2 adjacent teeth.  
       BACKGROUND OF THE INVENTION  
       [0003]     Dental dams and Class III matrices, e.g. a mylar foil, are commonly used in oral surgery and conservative dentistry. The use of the dental dam, or Class III matrix, isolates the teeth or tooth being treated from other tissues in the mouth and throat. The dam, comprised of a thin flexible piece of elastomeric material, is typically manufactured from a latex material, though alternatively it can be manufactured from silicone or nitrile rubber. The dental dam improves the efficiency of the dental operation by assuring a dry working area during all steps of the operation. Further, the dentist or oral surgeon is protected from infectious disease that may reside in the mouth or throat of the patient.  
         [0004]     The dental dam is secured in place by first fitting the dam to a rubber dam frame, which is positioned over the face and is dimensionally larger than the opened mouth to allow the dentist or oral surgeon ready access to the tooth or teeth requiring attention. Holes are then punched in the dam corresponding to the teeth that will be exposed through the dam. Alternatively, the dam is first punched to expose the teeth, and thereafter the edges of the dam are affixed to the rubber dam frame.  
         [0005]     Once the dam is positioned to expose the teeth, it must be stabilized from movement during treatment by the dentist or oral surgeon by some type of retaining system. Previously, a retainer clamp was used to stabilize the dental dam. This clamp consists of four prongs and two jaws connected by a bow. Stabilization using this clamp is optimized if the clamp is configured to a specific tooth within a narrowed tolerance range. Failure to closely match the retainer clamp to the tooth tends to permit slippage or unwanted movement of the dam during the surgical or conservative procedure. This movement may also result in formation of an inferior seal around the teeth that causes fluid to drain into the area being treated.  
         [0006]     For these and other reasons, it would be desirable to provide a retaining device that addresses these and other deficiencies encountered in stabilizing the dental dam, as well as providing a method for retaining a dental dam, or Class III matrix, which is neither complicated nor causes iatrogenic damage.  
       SUMMARY OF THE INVENTION  
       [0007]     In one embodiment of the present invention, a dental or clamping cord includes a core portion and a clamping portion. The core portion is of a first diameter and includes longitudinally arranged fibers. The clamping portion is of a second diameter greater than the first and includes a section of the fibers arranged longitudinally along and outward of the core portion, these fibers having interstices therebetween. The clamping portion further includes a polymeric material that surrounds the outwardly arranged fibers and substantially fills the interstices therebetween. The resulting clamping cord is so configured to permit the core portion of a first diameter to be inserted or slipped through a contact point between two adjacent teeth and pulled, or slid, therethrough whereby the greater second diameter of the clamping cord is of sufficient diameter to become lodged in the space between the two adjacent teeth.  
         [0008]     In another aspect of the invention, a method is provided for retaining a dental dam positioned over and around teeth in the mouth of a patient by selecting a length of the core portion of the dental or clamping cord, inserting the core portion in a space between at least two adjacent teeth, and moving the clamping cord axially through the space until the clamping portion becomes lodged in the space or spaces between adjacent teeth. The core portion also may be used to facilitate placement of the dental dam around the teeth, whereby the core portion is slipped between adjacent teeth and forced against a surface of the dental dam so that the teeth may be received through corresponding openings in the dental dam.  
         [0009]     In another embodiment, a Class III matrix likewise can be affixed in place by inserting the clamping cord between the tooth receiving the Class III matrix and an adjacent tooth, and thereafter pulling the clamping cord axially through the space between these two teeth until the larger diameter clamping portion of the clamping cord wedges the Class III matrix into position. In an exemplary embodiment, the clamping cord includes an optional palatinal stopper attached to, or integrated with, an end of the clamping portion. In practice, after insertion of the clamping cord, the clamping portion is moved between the adjacent teeth until the palatinal stopper abuts against the Class III matrix, wherein the stopper is pressed against the palatinal teeth surfaces. When the clamping cord wedges between the teeth, the palatinal stopper helps hold the Class III matrix in position, such as for filling a cavity.  
         [0010]     In connection with the method of either retaining a dental dam, or a Class III matrix, the clamping cord can be cut a short distance from the point of wedging between adjacent teeth. This will not adversely affect the quality of the stabilization of either the dental dam or the Class III matrix, but will provide fewer obstructions for the dentist or oral surgeon during the treatment procedure.  
         [0011]     By virtue of the foregoing, there is provided an improved clamping cord that may be inserted through or between at least two adjacent teeth and thereby, after wedging between the teeth, serves to effectively stabilize a dental dam or Class III matrix position. 
     
    
     BRIEF DESCRIPTION OF THE DRAWING  
       [0012]     The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the general description of the invention given above, and detailed description given below, serve to explain the invention.  
         [0013]      FIG. 1  is an overhead view of the clamping cord depicting the smaller diameter core portion and larger diameter clamping portion.  
         [0014]      FIG. 2  is a cut-away side view of the clamping cord depicting the smaller diameter core portion, transitioning to the larger diameter clamping portion.  
         [0015]      FIGS. 3A-3D  diagrammatically depict the steps of pushing the dam between two teeth using the core portion of the clamping cord, and then inserting, pulling and wedging the clamping cord between two adjacent teeth in a mouth fitted with a dental dam and rubber dam frame holder.  
         [0016]      FIG. 3E  is a diagrammatic depiction showing the clamping cord wedged between two adjacent teeth and cut to minimize obstructions in the treatment area.  
         [0017]      FIG. 4  is a diagrammatic depiction of the use of the clamping portion of the clamping cord pulled between two adjacent teeth, one tooth being fitted with a Class III matrix.  
         [0018]      FIGS. 5A and 5B  are cut-away side perspective views of another embodiment of the clamping cord of the present invention showing a palatinal stopper associated with an end of the clamping portion.  
         [0019]      FIGS. 6A-6C  diagrammatically depict the use of the clamping cord of  FIGS. 5A and 5B  inserted, pulled, and secured between two adjacent teeth, in an alternative procedure for stabilizing a Class III matrix. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0020]     With reference to  FIG. 1 , the clamping cord  2  of the present invention includes a core portion  4  and a clamping portion  6 . Optionally, the clamping cord  2  may have a section of core portion  4  extending from both ends of the clamping portion  6 , thereby permitting introduction of the clamping cord  2  between multiple sets of teeth.  
         [0021]      FIG. 2  depicts the clamping cord  2  in cross-section, showing the core portion  4  in the depicted embodiment having longitudinally arranged fibers  12 , which extend the length of the clamping cord  2 . The longitudinally arranged fibers  12  may be round or flat, natural or synthetic, and may be coated with a wax, polytetrafluoroethylene (PTFE), or other suitable lubricant commonly known in the art, unless the treatment process for the clamping portion  6 , as described below, would be adversely affected by such a coating. The fibers  12  may include nylon, polyester, polypropylene, natural fibers like cotton, or other materials capable to impart tensile strength. The core portion  4  of the clamping cord  2  is shown as being circular, or round, in shape but also may include other configurations, such as polygonal, and preferably includes a diameter, or width, of about 0.1 to 0.5 mm.  
         [0022]     The clamping portion  6  transitions from the core portion  4  at point A and increases in diameter to a generally maximum diameter at point B thereon. The clamping portion  6  similarly is shown as being circular, or round, in shape but also may include other configurations, such as polygonal, and preferably includes a diameter, or width, of about 0.5 mm up to a maximum of about 5 mm. Alternatively, the clamping portion  6  may present some variability in maximum diameter along its length.  
         [0023]     The clamping portion  6  includes longitudinally arranged fibers  12  disposed outwardly of the core portion  4 . In an exemplary embodiment, the longitudinally arranged fibers  12  are originally part of the core portion  4  prior to treatment involving an air jet or brush. This treatment opens the original tightly arranged fibers to create a fibrous portion outward of an untreated core portion  4  with fibers  12  having expanded volume interstices therebetween longitudinally arranged outward of the core portion  4  but still physically connected to the core portion  4 . Alternatively, longitudinally arranged fibers  12  can be arranged over a section of the core portion  4  in a separate procedure, for example, as a sleeve (not shown). In this alternative embodiment, it is preferred that some type of anchoring be effected between this outwardly applied sleeve of longitudinally arranged fibers  12  and the core portion  4  to minimize axially resiliency.  
         [0024]     The remainder of the clamping portion  6  is comprised of a polymeric elastic material  16  such as silicones, thermoplastic elastomers, or polyurethanes (PUR) that is applied onto the longitudinally arranged fibers  12  disposed outwardly of the core portion  4  to substantially impregnate the interstices thereof, following by a curing or other setting step. The polymeric elastic material  16  exhibits relatively low axially resiliency due to the existence of a plurality of axial anchoring points  20  which serve to substantially prevent movement of the polymeric elastic material  16  relative to the longitudinally arranged fibers  12 . The clamping portion  6  of the clamping cord  2  preferably includes a hardness of about 10 to 90 Shore A.  
         [0025]     The polymeric elastic material  16  in one embodiment is medical grade silicone. Alternatively, other polymeric materials can be used, such as but not limited to thermoplastic elastomers like Santoprene® available from ExxonMobil Chemical, Dynaflex® available from GLS Corporation, Pebax® available from Arkema, or polyurethane Pellethane® available from Dow Chemcial, etc. In addition, the polymeric material may be colored and/or contain one or more additives to reduce friction.  
         [0026]     In an alternative embodiment, the clamping cord  2  incorporates a palatinal shaper  22 , as depicted in  FIGS. 5A and 5B . The clamping cord  2 , at an end of the clamping portion  6 , has affixed thereto a palatinal stopper  22 , comprised in turn of a net component  25  and a polymeric-shaped component  26 . The net component  25  is fibrous and preferably of the same or compatible composition to the fibers  12  of the core portion  4 . As an alternative, ductile metallic or plastic fibers can be utilized to produce the net component  25  such as by being inserted between the polymeric-shaped component  26  and the end of the clamping portion  6 . To minimize radial resiliency, the fibers of the net component  25  preferably are anchored to fibers  12  either in the core portion  4 , the clamping portion  6 , or both, prior to the incorporation of the polymeric elastic material  16 . The polymeric-shaped component  26  is preferably of the same or compatible composition to the polymeric elastic material  16 . As indicated above, the clamping portion  6 , as shown in  FIGS. 5A and 5B , may present some variability in diameter along its length, i.e. is at a lesser diameter proximal the core portion  4  than proximal the palatinal stopper  22 , for use with Class III cavity application, as further explained below.  
         [0027]     Referring to  FIGS. 3A-3E , dental dam  30  is depicted being fitted over teeth  32  by use of the core portion  4  of the clamping cord  2 , and thereafter secured about the teeth  32  by use of the clamping portion  6  of the clamping cord  2 . In practice, as best shown in  FIG. 3A , a rubber dam frame holder  34  is arranged outward of the opened mouth, and receives the outer dimension of the dental dam  30  over retaining points  36 . The core portion  4  of the clamping cord  2  can be inserted between any adjacent teeth in the mouth, and against the dental dam  30 , which has openings  33  adapted to fit around the teeth  32 . The core portion  6  can then be forced upwards against the dental dam  30  so that the teeth  32  may be received through the openings  33 .  
         [0028]     As best shown in  FIGS. 3B and 3C , to prevent movement of the dental dam  30  downward over the teeth  32  after the dental dam  30  is in place, the core portion  4  of clamping cord  2  is brought into position, such as between two teeth  32   a  and  32   b . The teeth  32   a ,  32   b  through which the core portion  4  of the clamping cord  2  is passed are upper molars  32   a ,  32   b , i.e. the second premolar and first molar. After the core portion  4  has been inserted between the adjacent teeth  32   a ,  32   b , the core portion  4  is pulled through the space between the two teeth  32   a ,  32   b  to eventually provide a wedging effect facilitated by the clamping portion  6  as shown in  FIG. 3D . The selection of which teeth to pass the clamping cord  2  therebetween is at the discretion of the dentist or oral surgeon, and is a function of the particular tooth or teeth subject to treatment, as well as the ease in maintaining the stability of the dental dam relative to the treatment area. Because of the low axial resiliency of clamping cord  2 , the clamping portion  6  can be drawn as far as desired by the dentist or oral surgeon through the space between teeth  32   a ,  32   b  as is necessary to effectively stabilize the dental dam  30 .  
         [0029]     With further reference to  FIG. 3E , that portion of the clamping cord  2  located more than a few millimeters outward of the space between teeth  32   a ,  32   b  is cut. The resultant wedge created by the clamping portion  6  is minimally obtrusive to the dentist or oral surgeon performing a treatment procedure, and the relatively high radial resiliency of the polymeric elastic material  16  allows for a secure wedging operation, thereby preventing movement of the remaining portion of the clamping cord  2  during the treatment procedure.  
         [0030]      FIG. 4  depicts a tooth  40 A fitted with a Class III matrix  42 , i.e. a mylar foil, for use with a Class III cavity application, and the clamping portion  6  of the clamping cord  2  having been inserted and pulled between the Class III matrix  42  and adjacent tooth  40   b  with the larger diameter clamping portion  6  wedging the Class III matrix  42  into position. As indicated above, it should be understood that the clamping portion  6  may present some variability in diameter along its length (See  FIGS. 5A and 5B ), which may permit easier initial wedging of the clamping portion  6  between teeth  40   a  and  40   b  as well as minimize patient discomfort in the instance an anesthetic is not permitted or utilized, such as for Class III cavity application, as represented by  FIG. 4 .  
         [0031]     In an alternative embodiment,  FIGS. 6A-6C  depict the tooth  40   a  fitted with the Class III matrix  42 , i.e. the mylar foil, and the clamping cord  2  having incorporated therein the palatinal shaper  22 , as depicted in  FIGS. 5A and 5B . In this series, clamping portion  6  of the clamping cord  2  is pulled between the Class III matrix  42  and adjacent tooth  40   b  until the palatinal stopper  22  abuts against the Class III matrix  42 , wherein the stopper  22  is pressed and adapted anatomically against the palatinal teeth surfaces with the larger diameter clamping portion  6  wedging the Class III matrix  42  into position. In addition, the clamping portion  6  of the clamping cord  2  further is wedged, in a manner as above described, between another set of adjacent teeth  43   a  and  43   b  so that the pressure of the palatinal stopper  22  is prevented from slackening against the Class III matrix  42 , thereby providing an ideal condition for filling the tooth  40   a . As above mentioned, the optional variability in diameter of the clamping portion  6 , as shown in  FIGS. 6A-6C , may permit easier initial wedging between teeth  40   a  and  40   b  may minimize patient discomfort in the instance an anesthetic is not permitted or utilized for Class III cavity application.  
         [0032]     Accordingly, there is provided the improved dental or clamping cord  2  that may be inserted through or between at least two adjacent teeth  32   a ,  32   b ,  40   a ,  40   b ,  43   a ,  43   b  and thereby, after wedging between the teeth  32 , serves to effectively stabilize a dental dam  30  or Class III matrix  42  position.  
         [0033]     While the invention has been illustrated by a description of various embodiments and while these embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such detail. Additional advantages and modifications will readily appear to those skilled in the art. Thus, the invention in its broader aspects is therefore not limited to the specific details, representative apparatus and method, and illustrative examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of applicant&#39;s general inventive concept.