Abstract:
An endodontic diagnostic instrument includes a handle configured for receiving a clamp or retainer which engages and clamps an applicator, which may be made of open-celled foam and which is saturated with a coolant or refrigerant. By utilizing the instrument, a doctor may place or selectively position the applicator against a tooth or multiple teeth to determine the tooth which generates pain.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention relates to endodontics, and more particularly, to an endodontic diagnostic instrument for use in determining which specific tooth or teeth cause pain to a patient. The pain may be generated by numerous causes, such as an inflamed nerve in the pulp of the tooth, an exposed root surface or decay. A patient may complain of bite sensitivity or to sensitivity or pain due to cold and/or heat. Conventional diagnosis may utilize coolant material for contacting a tooth to determine which tooth is the one which is the situs of the pain. Previously, traditional techniques utilizing cold, contemplate using a ball of cotton, which is held by cotton pliers or tweezers, which is saturated with some type of refrigerant. Other methods may utilize dry ice to determine the tooth which is causing the patient&#39;s pain. 
         [0002]    The present invention is directed to a hand-held endodontic instrument specially adapted to cold test a tooth or multiple teeth in a controlled application and sequence. To this end, the present invention utilizes a handle which is configured for receiving a clamp or retainer which in turn engages and clamps an applicator, which may be made of open-cell foam, which in turn is saturated with a refrigerant. By utilizing the instrument as described, a doctor may place or selectively position the applicator against a tooth or multiple teeth to determine the tooth which generates the pain. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]      FIG. 1  is a view showing the instrument, including its handle, detachable retainer and applicator, prior to a dental coolant being applied to the applicator to chill the applicator. 
           [0004]      FIG. 2  is a view, enlarged from that of  FIG. 1 , showing the retainer, in its folded out, extended position, prior to clamping onto an applicator. 
           [0005]      FIG. 2A  is a view of the retainer of  FIG. 2 , showing it being folded or pivoted into its deployed position prior to insertion in the holder. 
           [0006]      FIG. 3  is a view, enlarged from that of  FIG. 1 , showing the applicator, in a folded position, just prior to insertion in the holder. 
           [0007]      FIG. 4  is a view, enlarged from that of  FIG. 1 , showing the applicator, in a folded position, being inserted in the holder. 
           [0008]      FIG. 5  is a perspective view of the applicator. 
           [0009]      FIG. 6  is a side view, similar to  FIG. 4 , showing the applicator, inserted into the holder, and being opened to permit insertion of the applicator. 
           [0010]      FIG. 7  is a view similar to  FIG. 6  showing the retainer clamped onto the applicator to hold it in position. 
           [0011]      FIGS. 8-12  show use of the instrument in locating a patient&#39;s tooth which is causing pain. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0012]    As shown in  FIG. 1 , an endodontic tool or instrument in accordance with the present invention is generally indicated at  10 , and includes a handle  12 , a detachable retainer  14 , and an applicator indicated at  16 .  FIG. 1  shows the instrument with its components, namely, handle  12 , retainer  14 , and applicator  16 , fully assembled. The instrument as shown is ready for a coolant to be applied to the applicator so that a doctor may position the applicator tip against a tooth or teeth to determine which is the situs of a patient&#39;s pain. The actual assembly, and a description of the components of the instrument will now be described. 
         [0013]    The holder of instrument  12  is dimensioned with a length for being comfortably held by a doctor, and includes a neck indicated at  12   a  and a wider or flared end  12   b  which further includes an extension  12   c  provided for fracture testing of a tooth. It will be noted that holder  12  also includes a hollow portion extending from its front inwardly from the holder proper, for receiving retainer  14 , in a manner to be described. As shown in  FIG. 2 , retainer  14  is an elongate member, which may be dimensioned generally in the range of about 4-5 inches, which includes a central notched portion or neck  18  and opposed aligned sections or arms  20  and  22 , each of which extend to an associated angled or contra angled member  24  and  26 , respectively. Arms  20  and  22  include projections  20   a  and  22   a  respectively, dimensioned to limit the extent to which arms  20  and  22  may be folded inwardly toward or against one another, when the arms are inserted into the open end of holder  12 . Arm  20  further includes a retention tab  20   b  and arm  22  includes a retention tab  22   b,  each of these are dimensioned for insertion and retention into corresponding, opposed apertures  15  and  17 , respectively, extending from a hollow bore or region  13  of holder  12 , when arms  20  and  22  are pivoted or folded over one another about neck  18 . 
         [0014]    Attention is now directed to the construction of angled portions  24  and  26 . As shown in  FIG. 2  each arm is inclined at an angle a, of about 35 degrees, or in the range generally of about 25-50 degrees, relative to the long axis, shown in dashed lines, of arms  20  and  22 . This inclination facilitates the doctor&#39;s ability to see exactly where the applicator tip is positioned when it is inserted near the posterior teeth in a patient&#39;s mouth. Each angled portion is dimensioned similarly overall, but there are important differences. Angled portion  26  includes extensions or pin  26   a  and post  26   b,  dimensioned for reception into corresponding aligned apertures  24   a  and  24   b,  respectively, in angled portion  24 . A stop or limit member is shown at  24   c,  which is to provide a guide as to the extent of insertion of applicator  16 . The retainer may be fabricated or molded of a semi transparent thermoplastic resin. 
         [0015]    Rounding out a description of applicator  16 , which is the final component, attention is directed to  FIG. 5 . As shown, applicator  16  is a small block of resilient, absorbent material, which may be formed as an open cell foam insert indicated at  28 , and includes a generally rounded or curved or convex end or tip  28   a  and an inwardly curved opposed end  28   b.  The applicator may be dimensioned about ½ to 1 inch in length and ¼ to ½ of an inch in width, and about ⅛ to 3/16 of an inch in thickness. The foam is flexible and adapted to be saturated with a conventionally available coolant (subsequent to being held in the retainer). It is readily mounted and firmly gripped by the retainer, which in turn is received in the handle. The assembly of the foam applicator and retainer will now be described. 
       Assembly of the Instrument and its Use in Endodontic Diagnostics 
       [0016]    The instrument has been designed to provide controlled cold testing of multiple teeth, and its assembly is simple. The applicator and retainer are not contemplated as being reusable, although the holder may be readily sanitized in an autoclave process, for repeated use. 
         [0017]    Initially, it is necessary to insert the retainer into the holder, and the steps for assembly are shown in  FIGS. 2 ,  2 A,  3  and  6 - 9 . The doctor selects the retainer, such as that shown in  FIG. 2 , and then bends or folds one portion over the other; for example, as shown in  FIG. 2A , where arm  22  has been folded toward and over arm  20 , about a fold axis indicated at neck  18 . Pivoting about neck  18  continues until a substantially complete fold is provided, as shown in  FIG. 3 . In this orientation, retainer  14  is now positioned for detachable insertion into holder  12 , (see  FIG. 8 ) and may be fully inserted until the retainer is in a secure position, with retention tabs  20   b  and  22   b  snapped into reception in apertures  15  and  17 , respectively.  FIG. 4  shows arms  20  and  22  as they are inserted into the hollow portion, prior to full insertion, when retention tabs  20   b  and  22   b  will be inserted in apertures  15  and  17 , respectively. Angled portions  24  and  26  are shown slightly spread apart, as they may be, during insertion, but once fully inserted may be positioned more adjacent one another. As shown in  FIG. 9  the doctor now spreads apart the arms, in particular angled portions  24  and  26  of retainer  14 , and inserts a single foam applicator  16  about half way into the assembly, as shown in  FIGS. 6 and 9 . Once the block of foam applicator is inserted, the angled arms are squeezed so that pin  26   a  and post  26   b  penetrate the foam and angled arms  24  and  26  engage and firmly grip the foam to secure it n place, as shown in  FIG. 7 . A tip portion of the foam extends outwardly from the retainer, as shown in  FIG. 7 . The doctor should gently pull on the foam to ensure that it is securely held in place, and some resistance should be felt. As can be seen in  FIG. 7 , portions of the foam of the applicator tip, although squeezed, are still substantially wide, as shown at  28   c  to retain coolant. In other words, the foam is not so compressed that it cannot retain coolant, in those portions that are compressed between angled portions  24  and  26 . 
         [0018]    As shown in  FIG. 10 , the foam applicator is saturated with a known dental coolant, from a spray can, for example, and the foam will turn to a frosty appearance as it cools. For diagnosing pulpal health, the doctor will apply the chilled foam to tooth structure, and by stimulating the nerve of a tooth, the doctor, through the patient&#39;s response, can ascertain which tooth is the sensitive one causing discomfort or pain. This is important because in some situations the patient may misidentify which tooth is the cause of the pain. In these cases, the tooth believed to cause the pain is called the referring site, but the pain really originates from a symptomatic tooth or teeth causing the problem. Use of the diagnostic instrument as described here will quickly and accurately generate a patient response leaving no doubt concerning the identity of the symptomatic tooth. 
         [0019]    The use of foam, firmly held and saturated with coolant enables controlled diagnosis by the doctor. Specifically, as the foam advances against a tooth, more cold will be transferred, and the doctor may advance cautiously if needed, until the patient&#39;s response clarifies where the pain originates.  FIGS. 11 and 12  show how a doctor may apply the applicator tip to teeth of a patient. For teeth located in the posterior portion of a patient&#39;s mouth, the angled portions  24  and  26  facilitate the doctor being able to see accurately where the applicator tip is positioned. This is shown to a certain extent in  FIG. 12 .