Abstract:
A conical dental bur for endodontic procedures, including exploration, deep troughing, enlargement of orifices, and canal navigation is presented. The bur of the present invention has a narrow, conical bur head with cutting members along its length. The head of the bur of the present invention is mounted to a shank that tapers to the bur head, allowing microscopic observations of endodontic procedures. The bur may be manufactured of tungsten carbide, diamond, ceramics, or other materials. Burs according to the present invention of various shapes and sizes, suited for particular procedures, may be packaged together in kits. Methods of using the burs in endodontic procedures are also disclosed.

Description:
BACKGROUND 
       [0001]    Access is an essential element to successful endodontics. Preparing the endodontic access cavity is a critical step in a series of procedures that potentially leads to the three-dimensional obturation of the root canal system. Access cavities should be cut so the pulpal roof, including all overlying dentin, is removed. The size of the access cavity is dictated by the position of the orifice(s). The axial walls are extended laterally such that the orifice(s) is just within this outline form. The internal walls are flared and smoothed to provide straight-line access into the orifice and the root canal system. Additionally, access preparations are expanded to eliminate any coronal interference during subsequent instrumentation. Access objectives are confirmed when all the orifices can be visualized without moving the mouth mirror. 
         [0002]    The traditional approach for gaining endodontic access in order to perform root canal procedures is achieved by utilizing conventional, large round shaped burs. This tactile based approach is fundamentally flawed. Round shaped burs are significantly more difficult to negotiate calcified canal systems, result in aggressive removal of precious dentin, and potentially damage the more critical cervical area of the tooth. 
         [0003]    When cutting endodontic access and burrowing the calcified tooth with round shaped burs, the tip of the round bur typically becomes slightly misdirected and severely gouges more of the tooth structure. As the access goes deeper into the tooth utilizing the conventional round bur, the access opening becomes wider internally which makes the tooth much more prone to fracturing and reduces the tooth&#39;s prospect for long term retention. 
         [0004]    The design of current endodontic burs is problematic in several respects. Surgical length right-angle round burs, and the Munce discovery bur, have a large head size, which can create centering problems, bur runoff and gouging. The round bur heads leave a rough finish, making anatomical mapping and reading difficult. 
         [0005]    Mueller burs have a thin shaft for visibility; however, the shaft is too flexible and cannot be directed toward locating canals. Because of the flexibility, pressure cannot be applied to the bur to force it to end cut. The round head is big and not conservative, and creates an uneven (ledging) surface in the tooth, and leave a poor, rough finish. 
         [0006]    The Gates Glidden instruments are problematic because the thin shanks of these instruments makes them difficult to “steer” away from high risk anatomy. As a Gates Glidden instrument straightens the coronal or “high curve,” it can shortcut across a fluting or furcation and weaken or even strip perforations. In addition, the Gates Glidden instruments require first the use of a round bur to access the pulp chamber, and several instruments of ever smaller size are needed to access the pulp chamber. 
         [0007]    Ultrasonic tips, while conservative in nature with a small diamond coated tips, wear down very quickly and are very costly. In addition, ultrasonics do not leave a smooth or polished surface. 
       SUMMARY 
       [0008]    The present invention is a uniquely designed bur with a long thin shank that can range from 17 mm to 45 mm in length. The bur heads are slender, conically tapered configurations that can range in head length from 0.039 inches to 0.177 inches with micro-diameter tips that can range from 0.016 inches to 0.059 inches in diameter. Cutting blades are located on the outer surface of the bur head and designed to efficiently cut in vertical and lateral directions to leave a polished dentin surface for better identification of hidden root canals and for easier canal mapping. The burs of the present invention are designed for non surgical endodontic treatment, with focus on gaining safer and less iatrogenic access to the pulp chamber and identification of the root canal system. 
         [0009]    A bur according to the present invention includes a drive shaft connectable to a motorized dental handpiece; a shank attached to the drive shaft with the same axis as the drive shaft; a head attached to the shank at a base. The head comprises a plurality of blades forming a conical shape from a narrow vertex to the base, with a shank that tapers in width from the drive shaft to the drilling head in a manner which allows microscopic observation of the head. 
         [0010]    In the bur according to the invention, the bur head and the shank may meet at a base, and the transition between the base of the bur head and the shank may be smoothly machined. The diameter of the base of the bur head may be no more than approximately 0.003 inches greater than the diameter of the shank at the transition between the base of the head and the shank. 
         [0011]    The bur may have a head of carbide material, such as tungsten carbide, stainless steel, hardened tool steel, sintered metals, sintered diamonds, sintered ceramics, plated diamond, diamond, zirconia, polymers, ceramics, ceramic oxides, lithium disilicate, titanium, nickel titanium, or aluminum. 
         [0012]    The bur of the present invention is a long thin bur that penetrates deep into the tooth for restoration purposes, primarily for root canal procedures. The bur provides self-centering characteristics that minimize the destruction of healthy tooth structure during the root canal procedure. 
         [0013]    The tapered conical head of the bur of the present invention allows for increased self-centering while reducing bur runoff and gouging associated with round burs. The round ended cone of the bur of the present invention cuts effectively but much more safely than a needle tipped bur. 
         [0014]    The bur of the current invention allows the use of direct microscope vision to allow a biomimetic shape, and can preserve the amount of peri-cingulum primary dentin and quality of residual dentin. The polished surface left by the dentin-carbide interface has better visual information than the chattered surface left by ultrasonic instruments, or scratchy dentin surface of a diamond bur. 
         [0015]    The tip size of the bur of the present invention is smaller than round burs, with the tip of the bur of the present invention being ¼ the size of a corresponding round bur. The spaces created by the conical bur of the present invention lend themselves to easier discovery of calcified canal systems. 
         [0016]    The shank of the bur is stiff enough to steer the bur with better control than prior art burs, with less potential to bend or break the shank, even though the tip is much smaller than other endodontic burs. 
         [0017]    The burs of the present invention can be packaged together in kits, with a number of different burs having different head lengths and diameters, designed for different endodontic tasks. 
         [0018]    Ideally, endodontic access cavities should parallel the principle of restorative dentistry where the axial walls of a “finished” preparation taper and provide draw for a wax pattern. Cleaning and shaping potentials are dramatically improved when instruments conveniently pass through the occlusal opening, effortlessly slide down smooth axial walls and are easily inserted into the orifice. Spacious access cavities are an opening for canal preparation. 
         [0019]    The burs according to the present invention may be packaged in a kit comprising one or more burs according to claim  1 , wherein the burs comprising the kit have heads of various sizes and shanks of various sizes for specialized endodontic procedures. 
         [0020]    The present invention also includes a method for endodontic deep troughing, comprising installing a bur according to the present invention in a dental handpiece, and troughing enamel or dentin with a light sweeping motion. 
         [0021]    The present invention also includes a method for endodontic exploration, comprising exploring dentin of a tooth using a dental handpiece installed with a bur according to the present invention, and using a dental microscope or loop to visually observe the endodontic exploration at the bur. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0022]    The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. In the drawings: 
           [0023]      FIG. 1  is a lengthwise schematic view of a first embodiment of the bur according to the present invention; 
           [0024]      FIG. 1A  is a side view of the head portion of a first embodiment of the bur according to the present invention; 
           [0025]      FIG. 1B  is a frontal view of the head portion of a first embodiment of the bur according to the present invention; 
           [0026]      FIG. 2  is a lengthwise schematic view of a second embodiment of the bur according to the present invention; 
           [0027]      FIG. 2A  is a side view of the head portion of a second embodiment of the bur according to the present invention; 
           [0028]      FIG. 2B  is a frontal view of the head portion of a second embodiment of the bur according to the present invention; 
           [0029]      FIG. 3  is a lengthwise schematic view of a third embodiment of the bur according to the present invention; 
           [0030]      FIG. 3A  is a side view of the head portion of a third embodiment of the bur according to the present invention; 
           [0031]      FIG. 3B  is a frontal view of the head portion of a third embodiment of the bur according to the present invention; 
           [0032]      FIG. 4  is a lengthwise schematic view of a fourth embodiment of the bur according to the present invention; 
           [0033]      FIG. 4A  is a side view of the head portion of a fourth embodiment of the bur according to the present invention; 
           [0034]      FIG. 4B  is a frontal view of the head portion of a fourth embodiment of the bur according to the present invention; 
           [0035]      FIG. 5  is a lengthwise schematic view of a fifth embodiment of the bur according to the present invention; 
           [0036]      FIG. 5A  is a side view of the head portion of a fifth embodiment of the bur according to the present invention; 
           [0037]      FIG. 5B  is a frontal view of the head portion of a fifth embodiment of the bur according to the present invention; 
           [0038]      FIG. 6  is a lengthwise schematic view of a sixth embodiment of the bur according to the present invention; 
           [0039]      FIG. 6A  is a side view of the head portion of a sixth embodiment of the bur according to the present invention; 
           [0040]      FIG. 6B  is a frontal view of the head portion of a sixth embodiment of the bur according to the present invention; 
           [0041]      FIG. 7  is a lengthwise schematic view of a seventh embodiment of the bur according to the present invention; 
           [0042]      FIG. 7A  is a side view of the head portion of a seventh embodiment of the bur according to the present invention; 
           [0043]      FIG. 7B  is a frontal view of the head portion of a seventh embodiment of the bur according to the present invention; 
           [0044]      FIG. 8  is a lengthwise schematic view of a eighth embodiment of the bur according to the present invention; 
           [0045]      FIG. 8A  is a side view of the head portion of a seventh embodiment of the bur according to the present invention; 
           [0046]      FIG. 8B  is a frontal view of the head portion of a seventh embodiment of the bur according to the present invention. 
       
    
    
     DETAILED DESCRIPTION 
       [0047]    The burs of the present invention are designed for use with a dental system having a dental unit connected to a dental handpiece. The dental unit provides power to the handpiece. The dental burs of the invention engage and are captively held by the handpiece which rotates the dental bur at a preselected rotational speed upon receipt of compressed air operating power from the dental unit. Each of the dental burs, as shown in the embodiments below, has a drive shaft engaged with the handpiece which provides the operative power from the dental unit to rotate the bur head and enable it to perform dental procedures on a tooth. The dental handpiece may be a low speed handpiece that rotates up to 5,000-80,000 rotations per minute, or a high-speed handpiece that rotates at 300,000-400,000 rotations per minute or greater. 
         [0048]    As shown in  FIGS. 1 ,  1 A, and  1 B, a first embodiment of a dental bur  300  according to the present invention includes a bur head  360  having a body  370  with a base  385  and an opposed vertex  380 . A drive shaft  355  is coaxially aligned with a longitudinal axis  350  of the body  370  for mounting in a handpiece. The drive shaft  355  in this picture is a surgical length friction grip type for use with high speed dental handpieces. 
         [0049]    The drive shaft  355  is connected to the head by a tapering shank  325  that tapers in diameter from the drive shaft  355  of the bur  300  to a neck  326  and mount  327 . The drive shaft and shank are typically constructed of metal, typically steel, and the bur head  360 , which may be made of tungsten carbide is mounted to the shank at mount  327 . The shank  325  tapers over a length of approximately 0.384 inches from 0.630 inches in diameter at the drive shaft  355  to approximately 0.025 inches at the neck  326 . The difference between the diameter of the shank  325  at the neck  326  and mount  327  and the bur head base  385  is minimized. The shank is designed so as to taper at a conical angle as the bur head, and to minimize the transition between the shank  325  and the bur head  385 , so that the microscopic sight line to the bur head  360  is uninterrupted. The shank  325 , however, is designed to be stiff so as to allow the bur to be self-centering. 
         [0050]    In addition, the bur head base  385 , neck  326  and mount  327  may be machined so as to form a smooth, gradual transition between the bur head  360  and the shank  325 . In this manner, the possibility of damage caused by the bur head base to the dentin or enamel upon withdrawal of the bur from the tooth is minimized. 
         [0051]    As shown in  FIG. 1 , the diameter of the head  360  of the dental bur  300  is 0.011 inches at a location near the vertex  380  of the bur. The bur head  360  has a conical shape and a length measured along the longitudinal axis  350  in this embodiment being 0.055 inches in length. The base  385  has a diameter of approximately 0.028 inches. It is understood that variations to the diameter width at the base  385  of the bur head  360  may be made. 
         [0052]    The bur head  360 , as shown in  FIG. 1A , includes an outer surface  310  having cutting members  320  extending outwardly from the outer surface of the bur head  360  and in which at least a portion of the cutting members  320  are positioned between the base  385  and vertex  380  and extend along the outer surface over the length of the head measured along the longitudinal axis. The bur head  360  with its elongate cutting members  320  may be formed of a carbide material such as tungsten carbide. The conical bur head  360  has its maximum diameter proximate the base  385  with the diameter of the bur head gradually decreasing as it extends toward the opposed vertex  380 . 
         [0053]    The cutting members  320  are preferably elongated blades having a height extending radially from the bur head  360 . The blades  120  are generally parallel to the longitudinal axis  350  of the body  370  and may curve from the vertex to the base at a helix angle of preferably two degrees. However, an acceptable range for the helix angle of the blades is zero degrees (0.degree.) to twelve degrees (12.degree.). Preferably six cutting members  320  are located on the bur head  360  with two opposing cutting members  335  extending past the remaining cutting members to form a drill tooth  140  (See  FIG. 1B ). The cutting members  320  provide a variable cutting intensity along the longitudinal axis  350  upon rotation of the dental bur  300  at a preselected speed. It is understood that diamonds or other durable cutting materials may selectively be employed as cutting members at the outer surface of the bur head. 
         [0054]    Each of the six cutting members  320  in  FIG. 1  has a rake face  341  that is the leading face of each blade. A rake angle of each cutting member  320  is defined as the angle of the rake face  341  of the cutting member to the cross-sectional axis or radius  342  of the dental bur  300  extending outwardly from the longitudinal axis of the dental bur. A preferred rake angle is minus eight degrees (−8.degree.) for each of the cutting members  320  of the bur head  360 . The rake angle for the blades of the bur head may selectively range from zero degrees (0.degree.) to minus fifteen degrees (−15.degree.). The rake face  340  may also vary along the length of the bur head  360 . 
         [0055]    The above-described embodiment of the dental bur of the present invention is intended for use in initial (cavosurface) access for small incisors, and may be used for troughing calcified canals and roof “sawing” in molars. 
         [0056]    In a second embodiment according to the present invention, shown in  FIGS. 2-2B , a bur  500  has a head similar in overall structure to the head according to  FIGS. 1-1B  in terms of the general conical shape and structure of cutters  520  and rake faces  541 ; however, the head in this instance has a length from base  585  to vertex  580  of approximately 0.094 inches, and the diameter ranges from 0.013 inches near the vertex  580  to a maximum of approximately 0.045 inches at the base. The shank  525  tapers in diameter over a length of approximately 0.342 inches from a diameter of approximately 0.630 inches at the drive shaft  555  to approximately 0.042 inches at the neck  526 , with the neck  526 , base  585 , and mount  527  machined to provide a smooth transition between the neck of the shank  525  and the bur head  560 . This embodiment of the bur is particularly useful for initial endodontic access in non-restored anterior and bicuspids. 
         [0057]    In a third embodiment, shown in  FIGS. 3-3B , a bur  600  also employs a surgical length friction grip drive shaft  625 . In this embodiment, the bur head  660  is longer, a length of approximately 0.132 inches, and a diameter widening from approximately 0.011 inches near the vertex  680  to 0.028 inches at the base  685 . The shank  625  tapers over a length of approximately 0.389 inches, from a diameter of approximately 0.630 inches near the drive shaft  655  to 0.025 inches at the neck  626 . Again, the transitions between the neck  626 , mount  627 , and head base  685  is machined to be smooth and gradual so as to prevent damage on withdrawal. The bur head  660  is similar to other embodiments, with its structure of six cutters  620 , a drive tooth formed of extended cutters  635 , and rake faces  641 . The long, narrow bur  600  according to this embodiment is particularly suited to deep troughing, and for navigating super ovoid and calcified canals. 
         [0058]    A fourth embodiment according to the present invention is shown in  FIGS. 4-4B . A bur  700  according to this embodiment utilizes a standard-length right angle type drive shaft  755  with latching member  756  for use with slow-speed handpieces, having a diameter of approximately 0.0920 inches. Like the previously described third embodiment, this fourth embodiment bur  700  has a conical head  760  with six cutting members  720  and rake faces  741 . The bur head  760  has a length of approximately 0.132 inches, widening from 0.011 inches near the vertex  780  to 0.028 inches at the base  785 . The shank  725  is machined to taper down from the drive shaft to the head in a stepwise progression, tapering from 0.0930 inches to approximately 0.039 inches over a portion  728  near the drive shaft  755  over a length approximately 0.118 inches along longitudinal axis  750 . The shank  725  has a second, non-tapered portion  724  having a diameter of 0.039 inches and a length of 0.233 inches. A third portion  729  of shank  725  tapers again from 0.039 inches to 0.025 inches at the neck  726  over a length of 0.137 inches along longitudinal axis  750 . In this manner, the shank  725  is designed to allow a sightline from the instrument to the bur head. The neck  726 , mount  727 , and bur head base  785  are machined to provide a smooth, gradual transition. The fourth embodiment of the bur of the present invention is designed especially for deep troughing, deep orifice enlargement, and for navigating calcified canals. 
         [0059]    In a fifth embodiment, shown in  FIGS. 5 ,  5 A, and  5 B, the bur  800  has a head  860  shaped and sized similarly to the bur head  560  of the second embodiment (see  FIG. 5 ), with a head length of approximately 0.094 inches, and widening from 0.013 inches near the vertex  880  to 0.042 inches at the base  885  along longitudinal axis  850 . The bur head is similarly shaped to other embodiments, with six cutting members  620 , rake faces  641 , and extended cutting members  635 . The shank  825  tapers in a stepwise progression, a first portion  828  having a length of 0.087 inches along longitudinal axis  850 , which tapers from 0.092 inches at the drive shaft to 0.053 inches in diameter. A second portion  824  has a diameter of approximately 0.053 inches over a length of 0.233 inches. A third portion  829 , which has a length of 0.211 inches, tapers from 0.053 inches to approximately 0.036 inches at the neck  827 . Again, the base  885 , mount  827 , and neck  826  are machined for a smooth, gradual transition. This fifth embodiment is particularly suited to de-roofing the pulp chamber, and deep orifice enlargement and calcified canals. 
         [0060]    A sixth embodiment of the invention, shown in  FIGS. 6 ,  6 A, and  6 B, is an extra-long right angle bur  900  intended for low-speed dental handpieces. The bur  900  has a head of the same shape, and size, as the first embodiment ( FIGS. 1-1B ), having a conical head  960  approximately  0 . 055  inches in length, having a diameter approximately 0.011 inches near the vertex  980  widening to 0.028 inches at base  985 . The bur head  960  has six cutting members  920  and six rake faces  941  with two of the cutting members  935  extending forward of the remainder. The bur  900  has a drive shaft  955  of approximately 0.0920 inches in diameter, with a latching member  956 . The shank  925  tapers in a stepwise progression, and has a portion  928  that tapers from 0.0920 inches at the drive shaft  955  to 0.039 inches over a length of 0.118 inches along longitudinal axis  950 . A second portion  924  has a diameter of 0.039 inches and a length of 0.483 inches. A third portion  929  tapers over a length of 0.120 inches along the longitudinal axis  950  from 0.039 inches to 0.025 inches at neck  926 . The neck  926 , mount  927 , and bur head base  985  are machined so as to provide a smooth, gradual transition from bur head  960  to shank  925 . 
         [0061]    This sixth embodiment is designed for deep troughing, retrieving separated instruments and navigating deeply calcified canals. 
         [0062]    A seventh embodiment, shown in  FIGS. 7 ,  7 A, and  7 B, is also designed for deep troughing, retrieving separated instruments and navigating deeply calcified canals. The head  1060  of bur  1000  is sized and shaped similarly to the embodiment shown in  FIG. 7 , having a length along longitudinal axis  1050  of approximately 0.094 inches, and widening from 0.011 inches in diameter near vertex  1080  to 0.028 inches at base  1085 . The bur head  1060  has six cutting members  1020  and six rake faces  1041  with two of the cutting members  1035  extending slightly forward of the remainder. The bur  1000  has a drive shaft  1055  of approximately 0.0920 inches in diameter, with a latching member  1056 . The shank  1025  tapers in a stepwise progression, and has a portion  1028  that tapers from 0.0920 inches at the drive shaft  1055  to 0.039 inches over a length of 0.118 inches along longitudinal axis  1050 . A second portion  1024  has a diameter of 0.039 inches and a length of 0.483 inches. A third portion  1029  tapers over a length of 0.121 inches from a diameter of 0.039 inches to a diameter of 0.025 inches at neck  1026 . The neck  1026 , mount  1027 , and bur head base  1085  are machined so as to provide a smooth, gradual transition from bur head  1060  to shank  1025 . 
         [0063]    An eighth embodiment, shown in  FIGS. 8 ,  8 A, and  8 B, is also designed for deep troughing, retrieving separated instruments and navigating deeply calcified canals. The head  1160  of bur  1100  has a similar cutter design as other embodiments, with a length of approximately 0.055 inches, widening from 0.013 inches in diameter near vertex  1180  to 0.028 inches at base  1185 . The bur head  1160  has six cutting members  1120  and six rake faces  1141  with two of the cutting members  1135  extending forward of the remainder. 
         [0064]    The bur  1100  of the eighth embodiment has a drive shaft  1155  of approximately 0.0920 inches in diameter, with a latching member  1156 . The shank  1125  tapers in a stepwise progression, and has a portion  1128  that tapers from a diameter of 0.0920 inches at the drive shaft  1155  to a diameter of 0.052 inches over a length of 0.089 inches along longitudinal axis  1150 . A second portion  1124  has a diameter of 0.052 inches and a length of 0.452 inches. A third portion  1129  tapers over a length of 0.204 inches from a diameter of 0.052 inches to a diameter of 0.036 inches at neck  1126 . The neck  1126 , mount  1127 , and bur head base  1185  are machined so as to provide a smooth, gradual transition from bur head  1160  to shank  1125 . 
         [0065]    Many other variations of burs according to the invention can be produced to suit various endodontic procedures. By way of example, the bur heads may be fitted with eight, twelve or another number of cutting blades placed around the diameter of the bur head. The cutter blades may be of a design where all of the blades meet at the vertex, with no two blades forming a drill tooth. It is contemplated that bur heads useful in endodontic procedures may range from a length of 0.039 inches to 0.177 inches, and a base diameter between 0.016 and 0.059 inches. 
         [0066]    The bur head in all of the aforementioned embodiments of the present invention may be a carbide material, such as tungsten carbide. However, any number of materials may be used to form the bur head, including stainless steel, hardened tool steel, sintered metals, sintered diamonds, sintered ceramics, plated diamond, diamond, zirconia, polymers, ceramics, ceramic oxides, lithium disilicate, titanium, nickel titanium, aluminum, and combinations of the aforementioned materials. 
         [0067]    It is also contemplated that burs of the current invention may be packaged together in kits so that all burs contemplated for an endodontic procedure can be grouped together. By way of example, it is contemplated that burs according to the aforementioned first, second, fourth, and fifth embodiments would be packaged together in a kit designed for anterior/bicuspid endodontic procedures. A kit including burs of the first, third, fourth, fifth, sixth, seventh, and eighth embodiments would be packaged together in a kit designed for molar endodontic procedures. The burs according to the present invention may be packaged in a kit by themselves, or a kit may also include other types of burs, including larger diamond or carbide burs designed for crown removal or initial access to molars. 
         [0068]    In using the kit for initial access, the clinician identifies the material makeup of any existing restorations (or lack thereof) that must be removed or penetrated to gain access. Once the material is identified, the appropriate bur is selected for the task. Once selected, the clinician applies only enough force to the bur to guide the bur. For deep troughing operations, a light sweeping motion is recommended. 
         [0069]    In using burs of the kit for endodontic exploration, the clinician identifies the task to be performed with the corresponding bur according to the present invention. The bur is installed in the dental handpiece and operated at the correct speed. The clinician may use a dental operating microscope or loops in order to provide magnification to the area being explored. The tapering shanks and conical shape of the bur heads are ideal for use with dental microscopy. 
         [0070]    The burs of the present invention create smoother incisions and troughs than round tipped, diamond-tipped and ultrasonic devices of the prior art. 
         [0071]    The burs according to the above embodiments provide numerous advantages over all prior systems in the following areas: 1) Cutting ability; 2) Positive control for deep troughing; 3) Flexibility; 4) Vision requirements; 5) Dentinal polishing/avoiding the dust and heat buildup; 6) Precision (anti-ledging, accuracy in location of root canals; 7) Cost (especially with respect to ultrasonic tips); 8) Greater efficiency; and 9) Reducing the number of instruments needed for a procedure. 
         [0072]    While a detailed description of the preferred embodiment of the invention has been given, it should be appreciated that many variations can be made thereto without departing from the scope of the invention as set forth in the appended claims.