Abstract:
Novel tools, accessories and methods for fixing a patient&#39;s upper and lower jaws together with flexible straps are disclosed. The tools are intended to either allow placement of a flexible strap to bind items to the teeth, or for using a flexible strap to fasten the upper and lower jaw into place, among other purposes. These accessories include a washer with a ratchet head for mounting on a bone screw, a bone screw with integrated ratchet head, dental blocks for use with the bone screws and washers, a flexible strap provided with a dissection tip for forcing the strap through tissue, and combinations thereof, and tools for inserting flexible straps through the gums, among other tools and accessories.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Patent Application Ser. No. 61/871,456 filed Aug. 29, 2013, the disclosure of which is incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    This invention relates generally to tools, devices and improved methods for providing intermaxillary fixation. The benefits of intermaxillary fixation, rigidly connecting the upper jaw to the lower jaw, are well known to promote healing of jaw fractures. Intermaxillary fixation is a common treatment to stabilize jaws for oral, plastic, maxillofacial, ENT and trauma surgeries. Further, intermaxillary fixation has been disclosed as a preferred stabilization method for the short term treatment of facial fractures in non-surgical settings, such as on the battlefield by military corpsmen. 
         [0003]    The general process of fixing the upper and lower jaw together for medical purposes has been in place for decades. Early efforts for intermaxillary fixation were rudimentary, generally ineffective, often exacerbated patient discomfort, and often failed to achieve desired results. An early process for intermaxillary fixation included the steps of boring holes through the patient&#39;s upper and lower gums, passing a wire through the holes and then twisting the wire to join the upper jaw to the lower jaw. That process required boring several holes through the patient&#39;s gums. Later efforts have included a variety of apparatuses and processes that include drilling holes, placing bolts, screws or anchors in to the patient&#39;s gums, jaw bones and palate. Although such processes increase the possibility of patient discomfort, infection and long-term bone and tissue damage, they are sometimes necessary to effectively fix the patient&#39;s jaws together. 
         [0004]    These methods have improved over the years including the device disclosed and described in U.S. Pat. No. 8,414,581 to Shah et al. Contemporary treatment methods tend to use non-invasive procedures when possible. The development of the Shah device was a significant advancement in the art in that it uses arch bars that fit adjacent to the outer surface of the patient&#39;s upper and lower teeth and are then fastened in place using a plurality of pliable zip or cable ties that connect the arch bars to individual teeth. Interarch receptacles provided on both the upper and lower arch bars can then be fastened together using reverse zip ties or double-ended flexible straps (described herein) thus holding the upper and lower jaw together. In many situations, this device eliminates the need for a physician to drill in to the patient&#39;s gum, palate or jaw to fix the upper and lower jaws together. The use of arch bars and zip tie connectors allows for easy and quick installation, removal and repair of the device. 
         [0005]    However, the Shah device works best when patients have substantially all of their teeth. When patients present with substantial trauma to their jaw and teeth or have multiple teeth removed or missing, then the interarch bar may not have enough support on the remaining teeth to be an effective treatment. Likewise, for patients that have dentures or no teeth whatsoever, the Shah device may be ineffective as disclosed and described in the previously referenced Shah patent. 
         [0006]    Accordingly, it is beneficial to provide a treatment that utilizes, to the extent possible, the noninvasive treatment disclosed in the previously referenced Shah patent, along with tools, devices and procedures that facilitate intermaxillary fixation when a patient has less than all of their teeth, dentures or no teeth at all. While the elimination of bone screws, drilling, boring and wire placement is a desirable goal, some of the historic techniques can be used in conjunction with more modern techniques and devices to substantially lessen the invasiveness of the intermaxillary fixation process. 
       SUMMARY OF THE INVENTION 
       [0007]    The instant invention is intended to overcome certain limitations that are present in the noninvasive intermaxillary fixation devices, such as the Shah device. More specifically, the invention is intended to meet the needs of patients who do not have enough teeth for the intermaxillary fixation arch bar system to work effectively and in instances where the patient presents with dentures, partial teeth or no teeth at all. The inventive tools, devices and methods disclosed herein utilize the best features of arch bar fixation devices, such as that disclosed by Shah, with some traditional methods that can be effective in those circumstances described. 
         [0008]    For example, a patient presenting with most of their teeth, but lacking teeth in one specific area of their mouth, a relatively common occurrence from trauma sustained in vehicle collisions or resulting from a sports injury, interarch bars can be used in those areas of the mouth where most of the teeth are present. However, in the area where teeth are not present, there would be insufficient stability to support an arch bar connected with an interarch receptacle and a strap with serrations. 
         [0009]    When described herein the female end of a zip or cable tie may be referred to as ratchet head, or as an interarch receptacle. Both terms refer to the case having a port through it for receiving a flexible strap. A flexible retention member or pawl is disposed inside the port of the ratchet head or interarch receptacle, as is commonly found with the female end of a zip or cable tie. The male end of a zip or cable tie may be referred to as a flexible strap. The flexible straps are provided with ratchet teeth or serrations. Some embodiments of the flexible strap are attached at one end to a ratchet head forming the common cable or zip tie. Some embodiments of the flexible straps are attached at one end to an inventive washer described in relation to the figures. Some embodiments of the flexible straps have two male ends, each with a section of ratchet teeth oriented in opposing directions, which may be referred to as a double-ended flexible strap. Each end of the double-ended flexible strap may be inserted into opposing interarch receptacles to fix the patient&#39;s jaws together, as is described in more detail in relation to the figures. The various embodiments of the flexible straps are inserted through the port on the ratchet head, thereby engaging the ratchet teeth on the flexible strap with the pawl and allowing insertion of the flexible strap but not its removal from the port. In some embodiments the flexible straps are flexible along their length, in one or both axes perpendicular to the longitudinal axis of the strap, so that they may be bent, curved or twisted in simple or compound curves as necessary. In some embodiments the flexible straps have limited extensibility or compressibility parallel to their longitudinal axis. 
         [0010]    In another embodiment of the invention, a unique hanger assembly provides a ratchet head, similar to those found on the Shah arch bar assembly, which can be connected to a screw fastened in to the patient&#39;s jaw bone. As shown in  FIG. 1 , a washer, or preferably, a slotted washer incorporated into a hanger can be placed onto the bone screw and secured in place by the screw head as the screw is inserted and tightened. The preferred washer includes an integrally formed ratchet head or interarch receptacle. In some embodiments, the screw would be positioned opposite an arch bar attached to existing teeth on the opposing jaw, so that the ratchet head would be presented opposite to an interarch receptacle mounted on the arch bar fastened to the existing teeth. The ratchet head may then be secured to the interarch receptacle using a double-ended flexible strap. 
         [0011]    For example, if the patient presented with no teeth on the left upper jaw but with teeth on the lower left jaw, an arch bar, similar to the Shah device, can be fastened to the lower teeth. At least one bone screw would be mounted into the upper left jaw bone of the patient opposite each arch bar receptacle provided on the arch bar fastened to the left lower teeth. An inventive washer assembly, an embodiment of which is depicted in  FIGS. 1A ,  1 B, and  1 C, may either be placed on the screw and simultaneously mounted with the bone screw, or slipped over the bone screw in the case of a slotted washer, and then secured in place by tightening the bone screw. The ratchet head incorporated into the washer assembly may be oriented so that a double-ended flexible strap can be inserted into both the ratchet head attached to the upper jaw, and to the interarch receptacle attached to the lower jaw so that when the patient&#39;s jaws are closed together the double-ended flexible strap holds the opposing arch bar receptacles and associated arch bar (on the lower teeth) in place. 
         [0012]    In situations where multiple teeth are missing from both the upper and lower jaw of the patient, it may be necessary to use multiple bone screws on both the upper and lower jaw to present enough ratchet heads or interarch receptacles so that the patient&#39;s jaws are maintained in the preferred rigid closed position by the flexible straps. 
         [0013]    In another embodiment of an intermaxillary fixation accessory, the innovative washer for fastening to a bone screw may also be attached to a flexible strap, an embodiment of which is shown in  FIG. 1C . When a bone screw is positioned opposite an interarch receptacle or a washer hanger assembly attached to the other jaw, the male end of the flexible strap may be inserted into the opposing receptacle to secure the two bone screws and thus the two jaws. A physician may alternate using the washer hanger assembly with either a washer with attached flexible strap or another washer hanger assembly and a double-ended flexible strap, as is most suitable for the application and circumstances. 
         [0014]    In some embodiments the bone screw must be inserted through the washer prior to placing the bone screw in the jaw. In other embodiments, the washer component is a slotted washer that has one end of its slot large enough to pass over the head of the bone screw and the other end of the slot small enough that it will not pass over the head of the bone screw. This allows the bone screw to be placed in the jaw and then the washer passed over the screw head and then manipulated so that the narrow portion of the slot underlies the head of the screw such that it cannot be removed without loosening or removing the bone screw. This also allows the washer assembly to be removed from the bone screw without fully removing the screw, in instances where the fastening assembly must be adjusted or replaced. Substantial care must be taken when applying washers with bone screws to not unduly compress gum tissue as doing so can cause permanent damage to the patient&#39;s gums. 
         [0015]    Another novel tool for intermaxillary fixation is a flexible strap-compatible bone screw. As shown in  FIGS. 2A ,  2 B,  2 C, and  2 D, the bone screw includes a threaded shaft and an elongated driving head for engagement with a driving tool as is common in the practice of seating bone screws. The driving head includes a ratchet head. The ratchet head may be integrally formed with the head of the bone screw or inserted into a cavity in the head of the bone screw. In some embodiments the ratchet head is inserted into and frictionally retained in a cavity or opening extending laterally through the elongated driving head of the screw. In some embodiments, the ratchet head may include a small ledge or other retention member along one edge of the case thereof to further support and retain the ratchet head in place. In other embodiments, as shown in  FIG. 2D , the ratchet head may be formed with at least one lip or protrusion that engages a portion of the head of the bone screw to prevent the ratchet head from passing through the cavity in the head of the bone screw. 
         [0016]    The inventive screw is installed in a traditional manner by driving the threaded portion of the shaft in to the bone of the patient. In an embodiment with the ratchet head incorporated into the head of the bone screw, the openings of the ratchet head are aligned as needed for clamping the jaws together, and are often oriented in an up and down orientation, with respect to the jawline of the patient. A flexible strap is inserted into the ratchet head. When the bone screw is mounted in the lower jaw, the orientation of the ratchet head and flexible strap is reversed. 
         [0017]    In another embodiment the ratchet head is not integrally formed with the bone screw and must be inserted into the cavity in the head of the bone screw. When this embodiment of the bone screw is installed in the jaw of a patient, the openings of the cavity and the optional retaining ledge are oriented generally toward the opposite jaw. The ratchet head is then installed into the cavity. Any protrusions on the ratchet head are disposed away from the opposing jaw so that the pulling force exerted by the flexible strap will pull the ratchet head farther into the cavity in the bone screw. In some circumstances, bone screws are presented in both the upper and lower jaw and are substantially aligned. A double-ended flexible strap may be provided and inserted into the ratchet heads on both bone screws. Thus, as the double-ended flexible strap is pulled upward through the ratchet head in the top bone screw and downward through the ratchet head in the lower bone screw, the patient&#39;s jaws are forced together. 
         [0018]    For those instances where a patient presents with upper, lower or both upper and lower dentures, the full interarch bar fixation assembly may not be effective because the dentures do not afford the stability necessary for good intermaxillary fixation. It is desirable, however, to fix the jaw in place with the dentures inserted so that as jaw bones heal they are healed in the configuration, orientation and spacing necessary to accommodate post-procedure denture usage that is appropriate and patient friendly. Fixing the jaws together without the dentures in place would likely result in improper post-procedure denture fit because the bone alignment would be different from the bone alignment at the time the dentures are originally fitted. 
         [0019]    Some current methods for intermaxillary fixation when a patient has dentures involve an elaborate process of wiring the dentures in place. For the lower dentures, a hole is generally made between the patient&#39;s gum and cheek tissue oriented downward and passing along the patient&#39;s jaw, exiting under the chin. A second hole is then bored upward through the floor of the patient&#39;s mouth adjacent the inner edge of the jaw and gums. This bore is generally made with a pointed or sharp instrument such as an awl or trochar. The dentures are then placed over the patient&#39;s gums and a wire is inserted through the hole between the patient&#39;s cheek and gum, passed downward below the patient&#39;s chin and then back upward and through the bore that is interior the patient&#39;s jaw bone. The wire is passed over the dentures and twisted or otherwise secured to itself so that the dentures are pulled downward on to the patient&#39;s gum and retained rigidly in place. A plurality of these circum-mandibular wires may be necessary to rigidly fix the lower dentures in place. In some cases this requires two sets of holes on either side of the patient&#39;s mouth, and in practice as many as four to six sets of holes may be used. 
         [0020]    For dentures on the upper jaw, multiple bone screws through the patient&#39;s hard palate can be used to secure the dentures in place. In the alternative, holes can be bored in the upper gum to allow wires to pass through these holes in the piriform aperture adjacent to the nose, and these wires are then tied around the circum-mandibular wires (wires around the lower jaw). Another alternative is to fix screws into the patient&#39;s upper jaw and then fastening wires to the screws which are then secured to bone screws in the lower jaw bone or, in some instances, to additional wires passed through holes drilled in the gum line (circummandibular wires). 
         [0021]    The use of wires to tie the dentures in place is not desirable because of the difficulty in positioning the wires, the propensity of the wires to cause sores within the patient&#39;s mouth and for the ends of the wires to gouge patient&#39;s jaws, cheek, tongue and the like. Moreover, as is well known, the use of wires in a patient&#39;s mouth often results in injuries to the physician, orthodontist and other medical staff during placement, adjustment and removal. One of the inventive devices that overcomes many of these limitations and drawbacks is an improved zip tie assembly that can be substituted for the wires in the process described above. In one instance, shown in  FIG. 4 , a flexible strap is presented that has a dissection tip at one end of the strap. This dissection tip allows the strap to be pushed through the tissues. The dissection tip is preferably formed from extremely rigid and sharp plastic, but can have an integrated metal cutting end formed from materials commonly found in scalpels, needles and the like. In some embodiments the dissection tip is sharp enough to easily pass through tissue, but not so sharp that it severs nerves and vessels. In some embodiments the dissection tip is molded to the flexible strap but is easily removed by cutting apart the plastic portion of the flexible strap adjacent the tip. 
         [0022]    In practice, the dissection tip of the flexible strap is used in a similar manner to an awl or trochar for creating tissue access for wire placement. The flexible strap is pushed, passed or guided through the tissue adjacent the gum and then passed through a small incision made below the patient&#39;s chin and then back up through the tissue thereby encircling the lower jaw and any associated dentures or dental blocks. Likewise, for application on an upper jaw of a patient, bores through the patient&#39;s gum, such as commonly used for that application are formed. A flexible strap can then be positioned through the bore around the jaw and fastened to a ratchet head on the other end of the flexible strap to hold the upper dentures in place. Multiple bores with multiple fasteners may be necessary to firmly secure dentures to the patient&#39;s upper gums. Once the dentures are fastened in place, the upper and lower jaws can be fixed together by traditional means, or by fastening interarch bars to the upper and lower teeth, whether natural or dentures, and then using an interarch bar attachment assembly such as that disclosed in the Shah patent. Alternatively, the innovative washer attachment system described herein may be utilized for intermaxillary fixation once the dentures are secured in place. 
         [0023]    In those instances when a patient presents with no teeth whatsoever and dentures are not provided or otherwise available, another embodiment of the invention may be used to securely fix the patient&#39;s jaws. As described above, it is not desirable to fix the patient&#39;s upper and lower jaws together for bone healing when there are no teeth or dentures present. Doing so results in improper jaw bone alignment during the healing process and may make it difficult, if not impossible, for subsequent use of dental implants or dentures. In other embodiments of the invention, as shown in  FIGS. 3A ,  3 B,  6 A, and  6 B, a unique set of dental blocks has been designed and developed to support the jaws and provide the proper spacing. One dental block is suitable for placement for the upper teeth, shown in  FIG. 3A , and the other block is designed for the lower teeth as shown in  FIG. 3B . The blocks are comprised of rigid or semi-rigid plastic portion that is sized to simulate the patient&#39;s teeth and a soft, formable or malleable portion, sometimes formed from plastic, that engages the patient&#39;s gum when the block is in place. When in place, the dental block holds the upper and lower jaw apart a sufficient distance such that when broken jaw bones are healed, suitable space has been provided between the jaw bones for proper placement of dental implants or dentures. In some embodiments, a single dental block may contact both upper and lower gums for a patient with no teeth. 
         [0024]    As shown in  FIGS. 3C ,  3 D,  6 A, and  6 B, each dental block is provided with multiple receptacles for receiving the male portion of a zip tie. The dental block is held in place using methods described above for securing dentures in place. The upper dental block may include screw holes for fastening the block in place with screws placed in the patient&#39;s palate. Once the dental blocks are fixed in place, double-ended flexible straps can be used in the receptacles on the dental blocks to fasten the upper and lower jaws together. 
         [0025]    Another inventive tool is a unique trochar or awl that is provided with a unique retention member at or substantially near the blade or dissection tip of the awl. The retention member is configured to engage and frictionally retain a knob provided on another embodiment of the flexible strap which may be used as a circum-mandibular strap. In some embodiments, a slot may be presented in the blade of the awl to engage a pin attached to the circum-mandibular strap being placed through tissue contemporaneously with advancement of the awl through the tissue. The awl is used in a manner similar to a trochar or awl would be used to form a path around the patient&#39;s jaw for securement of dentures or a dental block as described above. Once the circum-mandibular cable has been placed around the patient&#39;s jaw as described, the cable is disconnected from the awl by simply disengaging the pin on the strap from the retention member. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0026]      FIG. 1A  is a perspective view of an embodiment of an intermaxillary fixation accessory. 
           [0027]      FIG. 1B  is an exploded perspective view of an embodiment of the Intermaxillary fixation accessory of  FIG. 1A . 
           [0028]      FIG. 1C  is a perspective view of an embodiment of a pair of opposed intermaxillary fixation accessories. 
           [0029]      FIG. 2A  is a perspective view of an embodiment of a bone screw for intermaxillary fixation with a ratchet head. 
           [0030]      FIG. 2B  is a top perspective view of the embodiment of the bone screw of  FIG. 2A . 
           [0031]      FIG. 2C  is a side perspective view of the embodiment of the bone screw of  FIG. 2A . 
           [0032]      FIG. 2D  is a partial exploded view of an embodiment of the bone screw and ratchet head of  FIG. 2A . 
           [0033]      FIG. 3A  is a perspective view of an embodiment of an upper dental block for intermaxillary fixation. 
           [0034]      FIG. 3B  is a perspective view of an embodiment of a lower dental block for intermaxillary fixation. 
           [0035]      FIG. 3C  is a perspective view of an embodiment of upper and lower dental blocks for intermaxillary fixation. 
           [0036]      FIG. 3D  is another perspective view of an embodiment of the upper and lower dental blocks for intermaxillary fixation. 
           [0037]      FIG. 3E  is a perspective view of an embodiment of a ratchet head with clip component. 
           [0038]      FIG. 3F  is a bottom perspective view of an embodiment upper dental block shown in  FIG. 3A . 
           [0039]      FIG. 3G  is a bottom perspective view of an embodiment of the lower dental block shown in  FIG. 3B . 
           [0040]      FIG. 3H  is a perspective view of an embodiment of a dental block. 
           [0041]      FIG. 3I  is a perspective view of the embodiment of a dental block of  FIG. 3H . 
           [0042]      FIG. 4  is a partial perspective view of an embodiment of a circum-mandibular strap with ratchet head and serrations and a blade for piercing tissue in certain procedures for intermaxillary fixation. 
           [0043]      FIG. 5A  is a perspective view of an embodiment of a tool for piercing tissue and inserting a circum-mandibular strap. 
           [0044]      FIG. 5B  is a perspective view of an embodiment of the tool of  FIG. 5A  and a modified circum-mandibular strap attached to the tool. 
           [0045]      FIG. 5C  is a detailed perspective view of a portion of the embodiment of the tool and strap shown in  FIG. 5B . 
           [0046]      FIG. 6A  is a top perspective view of an additional embodiment of a dental block. 
           [0047]      FIG. 6B  is a bottom perspective view of an additional embodiment of a dental block. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0048]    Referring now generally to the drawings, the instant invention relates to devices to improve intermaxillary fixation for patients who do not have all, or any, of their teeth. The inventive devices and methods disclosed herein may be utilized separately or in conjunction with arch bar fixation devices described in the Shah patent to provide intermaxillary fixation for patients missing some or all of their teeth. 
         [0049]    In various embodiments of the devices disclosed herein, various ratchet components and straps with ratchet teeth are described. In the depicted embodiments, the straps are provided on one surface with a gear rack section provided with a plurality of ratchet teeth or serrations. A first or male end of the strap may have a narrowing or pointed end or a blunt end. The strap itself may be a flat tape, have a circular cross-section, or other similar shapes. The strap is preferably formed from a flexible but strong material. In some embodiments, a second end of the strap is provided with a ratchet head with a port through the head. Inside the port, a pawl is provided to engage ratchet teeth disposed on the strap. When the first end of the strap is inserted through the port in the ratchet head, the ratchet teeth engage the pawl to allow the strap to be pulled through the port but not to be retracted from the port. 
         [0050]    For clarity, the second end with the ratchet head, sometimes referred to as the female end, of a zip tie or strap may be referred to herein as an interarch receptacle and the first or male end may be referred to as a flexible strap provided with ratchet serrations or teeth. It should be understood that the interarch receptacle includes a port and a flexible retention member, or pawl, as is commonly found with the ratchet head, or female end, of a cable or zip tie. 
         [0051]    Some embodiments of the flexible straps are attached at one end to an inventive washer described in relation to the figures. Some embodiments of the flexible straps have two male ends, each with a section of ratchet teeth oriented in opposing directions, which may be referred to as a double-ended flexible strap. Each end of the double-ended flexible strap may be inserted into opposing interarch receptacles or ratchet heads to fix the patient&#39;s jaws together, as is described in more detail in relation to the figures. The various embodiments of the flexible straps are inserted through the port on the ratchet head, thereby engaging the ratchet teeth on the flexible strap with the pawl and allowing insertion of the flexible strap but not its removal from the port. In some embodiments the flexible straps are flexible along their length in one or both axes perpendicular to the longitudinal axis of the strap, so that they may be bent, curved or twisted in simple or compound curves as necessary. In some embodiments the flexible straps have limited extensibility or compressibility parallel to their longitudinal axis. 
         [0052]    As best shown in  FIGS. 1A and 1B , a first embodiment of an intermaxillary fixation accessory is a unique hanger assembly  100  that provides an interarch receptacle or ratchet head  102  for connecting to a bone screw  104  to be fastened into a patient&#39;s jaw bone. The screw  104  includes a threaded shaft  105  and a driving head  107  at one end of the threaded shaft  105 . A receptacle hanger  101  comprises an interarch receptacle or ratchet head  102  and a washer  106  attached to ratchet head  102  by spacer bar  108 . In some embodiments the washer  106  is elongated or slotted and is provided with a hole  109 . When in use the shaft  105  of bone screw  104  is disposed through the hole  109  in washer  106  and washer  106  is disposed adjacent to head  107  of bone screw  104 . The spacer bar  108  separates the ratchet head  102  a predetermined distance from the washer  106 . The port of the ratchet head  102  is disposed substantially perpendicular to the washer so that a flexible strap secured in the ratchet head extends substantially perpendicular to a bone screw inserted through the hole in the washer. 
         [0053]    When installed in a patient&#39;s mouth, the bone screw  104  is fastened into the jaw bone of the patient in a location where one or more teeth are missing. The installed hanger assembly  100  disposes the ratchet head  102  adjacent to the areas of missing teeth so that an interarch receptacle on an arch bar may be secured to the ratchet head  102  and thus to the jaw. In some embodiments, bone screw  104  may be provided with a bearing area  103  disposed on the shaft  105  of the bone screw  104  adjacent to the head  107 . The bearing area provides a surface for contact with the washer  106  to allow the washer to rotate smoothly. The surface of bearing area  103  may be flat, concave, convex or textured as desired. 
         [0054]    As shown in the previously referenced Shah patent, interarch receptacles are positioned along the arch bar for the receipt and retention of a flexible strap or the male end of a zip tie. In use, the inventive receptacle hanger  101  is positioned on the patient&#39;s jaw opposite an interarch receptacle, or zip tie receptacle, mounted on the arch bar or ratchet head attached to another bone screw  104  on the opposing jaw of the patient. 
         [0055]    For example, if the patient presented with no teeth on the left upper jaw but has teeth on the lower left jaw, an arch bar may be fastened to the lower teeth. A bone screw  104  could be mounted in to the upper left jaw bone of the patient opposite the interarch receptacles presented on the arch bar fastened to the left lower teeth. In some embodiments the washer  106  of the receptacle hanger  101  may be placed over the threaded shaft  105  on the screw  104  and simultaneously mounted with the bone screw  104 . In other embodiments the slotted or wide portion of the washer  106  may be slipped over the driving head  107  of the bone screw  104  after it has been secured in the patient&#39;s jaw bone. The interarch receptacle  102  is generally oriented so that a zip tie or flexible strap having reversed teeth at opposite ends can be inserted in to both the interarch receptacle and the opposed ratchet head  102  so that when the patient&#39;s jaws are closed together the zip tie or flexible strap holds the opposing arch bar receptacle and ratchet head  102  and associated arch bar (on the lower teeth) in place. 
         [0056]    In situations where multiple teeth are missing from both the upper and lower jaw of the patient, it may be necessary to use multiple bone screws  104  and receptacle hangers  101  on both the upper and lower jaw to present enough ratchet heads so that the jaws are maintained in the preferred rigid closed position by the flexible straps. 
         [0057]    Referring now to  FIG. 1C , in some embodiments of the invention a flexible strap  110  with integral washer  112  is utilized. The innovative washer  112  is similar in shape and configuration to embodiments of washer  106 , and is attached to or integrally formed as part of a first end  111  of flexible strap  110 . The flexible strap  110  is provided with ratchet serrations  113  on at least one surface thereof for engaging the ratchet head  102 . When the bone screws  104  are disposed in opposing jaw bones of a patient, washers  112  and  106  may be engaged on the bone screws  104  as described in relation to  FIG. 1 . The second end  114  of flexible strap  110  is inserted in the opposite ratchet head  102  and pulled until the jaws are in a closed position to hold the patient&#39;s jaws together. A physician may alternate using a bone screw with either a washer  112  or a receptacle hanger  101  as appropriate in the circumstances. 
         [0058]    Referring now to  FIGS. 2A-2D , in another embodiment of an intermaxillary fixation accessory, a zip tie compatible or flexible strap compatible bone screw  200  is utilized for intermaxillary fixation. The bone screw  200  includes an elongated driving head  202  for engagement with a driving tool and a threaded shaft  204 . The elongated driving head  202  extends upwardly from the shaft  204  of the bone screw, and the depicted embodiment of the head  202  is generally cylindrical but may also have a hexagonal or other shaped cross-section. In the depicted embodiment the top surface  203  of the driving head  202  is provided with structures for engaging a driving tool such as a square or phillips screw driver, while in other embodiments the shape of driving head  202  may be capable of engagement by a tool such as a wrench. Within the elongated driving head  202  a ratchet head is provided for receiving a flexible strap. The ratchet head may be integrally formed as part of the elongated driving head  202 , or it may be removable as depicted in  FIGS. 2A-2D . 
         [0059]    In some embodiments, the driving head  202  includes a cavity  206  for receiving a removable ratchet head  208 . The cavity  206  is an opening laterally through the elongated driving head  202  of the bone screw  200  in to which a ratchet head  208  may be inserted. The ratchet head  208  may be frictionally retained, adhered or otherwise secured in cavity  206 . The cavity  206  may include a small ledge or other retention member along one edge  211  of the cavity  206  to further engage and retain the ratchet head  208  in place. In some embodiments, the ratchet head  208  may be formed with at least one lip or protrusion  210  that engages the driving head  202  adjacent the cavity  206  to prevent the ratchet head  208  from passing through the cavity  206 . In some embodiments, ratchet head  208  may also be provided with slots or flanges  212  to engage the edge  211  of cavity  206  to engage and retain the ratchet head  208  in cavity  206 . 
         [0060]    The bone screw  200  is installed by driving the threaded shaft  204  into the bone of the patient. The openings of the cavity  206  are preferably oriented in a vertical position with respect to the jawline of the patient. When the screw  200  is installed in the jaw of a patient, the ratchet head  208  is disposed in cavity  206  with protrusion  210  disposed generally on the side of driving head  202  away from the opposite jaw. A flexible strap such as  110  is then installed into the ratchet head  208  by passing one end of the flexible strap through the ratchet head  208 . When the other end of the flexible strap is attached to another interarch receptacle, ratchet head, or bone screw and tightened to hold the jaws of the patient together, the flexible strap will pull interarch receptacle  208  into cavity  206  maintaining protrusion  210  securely against the edge of cavity  206 . The protrusion  210  engages a portion of the driving head  202  adjacent to the cavity  206  such as edges  211  and prevents the ratchet head  208  from passing through the cavity  206 . Where opposing screws are presented in both the upper and lower jaw, a reversing zip tie or double-ended flexible strap, where the teeth on one end of the flexible strap are reversed from the teeth on the other end, is provided. The teeth disposed in opposite directions allow each end of the double-ended flexible strap to be inserted into opposing interarch receptacles or ratchet heads for securing the opposite jaws together. This double-ended flexible strap is positioned within and manipulated through the ratchet head  208  and secured by the ratchet inside the ratchet head  208  engaging the teeth on the flexible strap. As the reversing zip tie or double-ended flexible strap is pulled through the ratchet head  208  and through the opposed interarch receptacle or ratchet head, the patient&#39;s jaws are forced together and secured in a closed position. 
         [0061]    In those instances when a patient presents with no teeth whatsoever on one or both jaws, and dentures are not provided or are otherwise not available, a different problem must be overcome. It is not desirable for bone healing to fix the patient&#39;s upper and lower jaws together when there are no teeth or dentures present. Doing so results in improper jaw bone alignment during the healing process and may make subsequent use of dental implants or dentures difficult, if not impossible. To overcome this problem, an inventive set of dental blocks (sometimes referred to as dental splints)  300  has been designed and developed, an embodiment of which is depicted in  FIGS. 3A-3D . 
         [0062]    An upper dental block  302 , shown in  FIGS. 3A and 3F , is suitable for replacement of the upper teeth and a lower dental block  304 , shown in  FIGS. 3B and 3G , is designed for replacement of the lower teeth. The blocks  302  and  304  may be comprised of substantially rigid portion or plate  306  designed to take the place of the patient&#39;s teeth and a soft, formable, malleable, or flexible or compressible portion  308  (shown in  FIGS. 3C and 3D ) that engages the patient&#39;s gum when the blocks  302  and  304  are in place. The general shape of the blocks  302  and  304  are semi-arcuate when viewed from above. In some embodiments they comprise a substantially semi-circular front portion with substantially linear wings extending substantially tangentially to the circumference of the semi-circular portion. In some embodiments the plate  306  is substantially flat and extends perpendicularly to the outside plate  301 . In some embodiments an inside plate  317  is provided adjacent to the inside edge of plate  306  and substantially perpendicular to the plate  306 . The inside plate  317  and outside plate  301  generally run around the inner and outer periphery, respectively, of the patient&#39;s gums. 
         [0063]    Blocks  302  and  304  may be provided in various sizes to fit different patient&#39;s bites. When in place, the dental blocks  302  and  304  hold the upper and lower jaws apart a sufficient distance such that when the jaw bones heal, suitable space has been provided between the jaw bones for proper placement of dental implants or dentures. If a patient has teeth on one jaw but not on the other, only one of blocks  302  and  304  may be necessary. 
         [0064]    In some embodiments, each dental block  302  and  304  is provided with multiple receptacles or ratchet heads for receiving the male end of a zip tie or a flexible strap. In some embodiments, the ratchet heads or receptacles may be fixedly or pivotally attached directly to the blocks  302  and  304  at various locations around the outside plate  301  of each block  302  and  304 . In the embodiment shown in  FIGS. 3A-3D , an attachment rail  303  is provided on each dental block  302  and  304 . The rail  303  extends around the outside plate  301  of the dental blocks  302  and  304 . In the depicted embodiment, the rail  303  is supported slightly separated from the outside plate  301  by a plurality of posts  305 . In other embodiments the rail  303  may be continuously connected to outside plate  301  or may be formed on or attached to discrete segments of outside plate  301 . Rail  303  has a generally rectangular cross-section, but may be provided with beveled or rounded edges as depicted in the figures, or may be circular in cross-section. 
         [0065]    Rail  303  provides a means of attaching a plurality of ratchet heads or receptacles  310  to the rail for attaching the dental blocks  302  and  304  to a patient&#39;s jaws and to the other dental block. In the depicted embodiment, bores, holes or indentations  307  are provided at numerous locations along the length of rail  303 . If indentations that do not extend completely through rail  303  are provided at locations  307 , a corresponding indentation may be provided on the inside surface of rail  303  facing the outside plate  301 . In some embodiments holes  307  will extend completely through rail  303 . In some embodiments, receptacles  310  may be provided with screws or locking pins for inserting into holes  307 . In other embodiments, such as that shown in  FIGS. 3C and 3D , receptacles or ratchet heads  310  may be provided with clip elements that clip over the rail  303  and engage the holes  307  from one or both sides with protrusions on the clip. The rail  303  with a plurality of receptacle mounting locations  307  allows for the positioning of the receptacles to be configured based on the circumstances and condition of the patient&#39;s teeth, gums and jaws. 
         [0066]    The upper edge  309  of the outside plate  301  of lower dental block  304  may be provided with various undulations, lower portions, higher portions, raised portions, or indentations along the length of the outside plate  301 . Similar undulations, raised portions or indentations may be provided on lower edge  311  of upper dental block  302 . The varying shape of the upper edge  309  and lower edge  311  may be designed to interact with the patient&#39;s teeth and the other dental block to create and maintain space for the patient&#39;s tongue and passageways between the dental blocks for airways, tubes, circum-mandibular straps, and other medical devices when the two blocks are in contact at the outside plates. 
         [0067]    Referring now to  FIG. 3C , an embodiment of the upper dental block  302  and the lower dental block  304  are depicted. A plurality of clip on receptacles or ratchet heads  310  have been attached to the rail  303  and a double-ended flexible strap  313  inserted into two opposing receptacles to prevent separation of the dental blocks  302  and  304 . Other double-ended flexible straps  313  would also be inserted at other locations with receptacles  310 . As can be seen in this figure, the clip on receptacles  310  are clipped on to the rail with the clip disposed away from the direction of force on the flexible strap that will be inserted into the receptacle. This orients the ratchet within the receptacle  310  in the necessary direction to engage the teeth on the flexible strap. 
         [0068]    The dental blocks  302  and  304  are held in place using methods described herein for securing dentures in place, some of which are depicted in  FIG. 3D . The upper dental block may include screw holes  312  for fastening the block in place with screws placed in the patient&#39;s palate. The holes  312  may be in an extension of plate  306  or an additional plate  318  attached to the inside wall  317  of the upper dental block  302 . 
         [0069]    Unique circum-mandibular straps  314  may be used to secure the lower dental block  304  in place. The circum-mandibular straps  314  are placed by methods similar to known methods of wiring lower dentures in place for intermaxillary fixation procedures. For securing the lower dental block  304  with circum-mandibular straps  314 , as best shown in  FIG. 3D , a hole is generally made between the patient&#39;s gum and cheek tissue oriented downward and passing along the patient&#39;s jaw, exiting under their chin. A second hole is then bored upwardly through the floor of the patient&#39;s mouth adjacent the inner periphery of the gum. This bore is generally made with a pointed or sharp instrument such as an awl or trochar. The lower dental block  304  is then placed over the patient&#39;s lower gums so that the gums engage and support the soft insert  308 . Although not shown in  FIG. 3C , a soft insert  308  is also provided on the lower surface of dental block  304  for contacting the lower gums of the patient. The circum-mandibular straps  314  are inserted through the hole between the patient&#39;s cheek and gum downward below the patient&#39;s chin and then back up through the bore that is interior the patient&#39;s gums. The circum-mandibular straps  314  are passed over the dental block  304  so that the dental block is pulled downward on to the patient&#39;s gum and retained rigidly in place. The male end of the circum-mandibular strap is then inserted into the ratchet head disposed on the other end thereof, and secured by the pawl and ratchet teeth on the strap. This procedure generally requires at least two circum-mandibular straps  314 , one on either side of the patient&#39;s mouth. As previously described, the dental blocks may be provided with grooves on edges  309  and  311  into which the circum-mandibular straps  314  are seated to prevent unwanted shifting, sliding or other movement of the circum-mandibular straps  314  along the dental blocks once they have been placed. 
         [0070]    Two perspective views of a similar embodiment of the dental block  302  is depicted in  FIGS. 3H and 3I . Similar numbers identify similar components of the depicted dental block. The embodiment depicted in  FIGS. 3H and 3I  may be used on either jaw and two of the depicted dental blocks may be used simultaneously on both jaws. 
         [0071]    Referring now to  FIG. 3D , in some embodiments a ratchet head or receptacle  310  is attached to one of the dental blocks  302  and  304  and may be secured to the jaw by a double-ended flexible strap  313  connected to a bone screw  104  and receptacle hanger  101  or a flexible strap compatible bone screw  200 , with the bone screw  104  or  200  fixed in the patient&#39;s jaw. In some embodiments, the patient&#39;s jaws may be secured to one another using a bone screw  104  and receptacle hanger  101  fixed in one jaw, and bone screw  104  fixed in the other jaw, with a flexible strap  110  with integral washer  112  secured on the bone screw  104  and inserted into the receptacle hanger  101  attached to the opposing jaw. 
         [0072]    Once the dental blocks are fixed in place, reverse zip ties or double-ended flexible straps  313  can be used in the receptacles  310  on the opposing dental blocks or opposing teeth to fasten the upper and lower jaws together. The edge  311  of upper block  302  may include an upper arcuate opening  315  and the lower block  304  may include a substantially similar, but opposing lower arcuate opening  316  so that when the dental blocks are in place, an annular opening is formed for access to the patient&#39;s mouth for cleaning, suction and the like, or in some instances, the placement of a breathing tube. 
         [0073]    Referring now to  FIG. 3E , an embodiment of a ratchet head  310  for use with a rail  303  is depicted. The ratchet head includes ratchet body  319  which contains the opening and pawl for receiving and retaining a flexible strap. A clip portion or member  320  extends from the side of the ratchet body  319  and fits around rail  303  so that it may be clipped on to the rail  303  at the desired location. The clip portion  320  contains two protrusions  321  that engage the holes  307  on rail  303  to secure the ratchet head  310  in place on the rail  303 . The protrusions  321  may be sloped (as shown in the figures) or otherwise shaped to allow them to be clipped onto the rail but to resist removal of the clip portion  320  from the rail  303 . 
         [0074]    One of the inventive intermaxillary fixation accessories that can be used to place circum-mandibular straps  314  is an improved zip tie assembly or strap, one embodiment of which is shown in  FIG. 4 . The zip tie or circum-mandibular strap  400  has a dissection tip  402  at the terminus of a first or male end  401  of the strap  400 . This dissection tip  402  may be conical or blade-shaped and sharp enough to allow the first end of the strap  400  to be pushed through the tissues surrounding a patient&#39;s jaws. In some embodiments the tip  402  is preferably integral to the strap  400  and formed from plastic that can be provided with a sharp edge, if needed, to facilitate advancement of tip  402  through tissue. In some embodiments the tip  402  may be separate from and attached to the male end of strap  400 . In some embodiments, the dissection tip  402  may be made of metal and molded onto the plastic of the zip tie. A sharp blade may take the place of the dissection tip  402  for some applications. 
         [0075]    In some embodiments, the male end  401  of strap  400  may have one or more sections  404  with a thinner profile or smaller cross-section than other portions of the strap  400  to ease insertion of the strap  400  through the patient&#39;s tissue. Between the sections  404  of the strap  400 , some embodiments incorporate sloping sections  406  gradually narrowing the thickness or cross-section of strap  400  as it approaches the dissection tip  402 . 
         [0076]    Strap  400  is provided on one surface with a gear rack section  408  provided with a plurality of ratchet teeth  410 . The second end of strap  400  is provided with ratchet head  412  with a port  414  through the head  412 . Inside the port  414  a pawl  416  is provided to engage ratchet teeth  410 . In some embodiments, the other ratchet heads described herein contain similar elements. As with the other straps used in the depicted embodiments of the invention, when the first end  401  of strap  400  is inserted through the port  414  in the ratchet head  412 , the ratchet teeth  410  engage pawl  416  to allow the strap to be pulled through port  414  but not to be retracted from the port  414 . 
         [0077]    In practice, the dissection tip  402  of the strap  400  is used like an awl or trochar for wire placement. The strap  400  may be pushed through the tissue adjacent the gum and then passed below the patient&#39;s chin, creating a small loop and then back up through the tissue so the strap  400  encircles the jaw and any associated dentures or dental block. As the strap  400  is pushed through the tissue, dissection tip  402  cuts the tissue sufficiently to allow the strap  400  through the tissue. 
         [0078]    Another inventive tool, as shown in  FIGS. 5A ,  5 B, and  5 C, is a unique tool  500  that is provided with a handle  502 , a shaft  504  and a unique retention member  506  at or substantially near the blade or dissection tip  508  of the tool  500 . In one embodiment, the retention member  506  is configured to engage and retain a knob or pin  512  provided near the first end of an embodiment of circum-mandibular strap  510 . In the depicted embodiment, the retention member  506  is provided with a retention slot  514  formed at or near the blade  508 . The blade  508  may be wider than the flexible strap in some embodiments. Further, the retention member  506  may include a nodule or detent  516  within the slot  514  to further engage and retain the knob  512  of the circum-mandibular strap  510 . The tool  500  is used in a manner similar to a trochar or awl to form holes in the patient&#39;s jaw or adjacent tissues for placing straps as described above to secure dentures or a dental block. As the blade end  508  advances through tissue, it pulls the first end of the circum-mandibular strap  510  through the tissue so that it is placed simultaneously as the tool  500  is advanced. Once the circum-mandibular strap  510  has been placed through the patient&#39;s jaw as described above, the knob  512  is disengaged from the slot  514  on the retention member  506 . Tool  500  may then be retracted back through the hole in the patient&#39;s jaw, leaving the strap  510  in place. The knob  512  or the end of strap  510  where knob  512  is attached, may be cut off the strap  510  so that the remainder of the strap  510  may be inserted into and secured by ratchet head  412 . 
         [0079]    Referring now to  FIGS. 6A and 6B , an additional embodiment of a dental block is depicted. This embodiment is a single piece dental block that may be used with patients that have no teeth on either upper or lower jaws. The dental block  600  is provided with a rigid plate  602  shaped in the approximate shape of the human jaw for receiving the gums of a patient. Cushions  604  and  606  are provided on the top and bottom of the block  602  to cushion the gums of the patient. An outer plate  608  is attached to the rigid block  602 . A rail  610  is attached to the outer surface of plate  608 . In some embodiments, the rail  610  may be integrally formed with the plate  608  or may be separated from plate  608  by a gap and supported by posts  612 . Rail  610  is provided with holes or indentations  614  similar to holes  307  described in relation to an earlier figure. In some embodiments, the plate  602  may comprise two slightly separated upper and lower plates attached to the outside plate  608 . In some embodiments, plates  602  may have inner plates  618  and  620  attached to the inner edge thereof. 
         [0080]    The general shape of the block  600  is semi-arcuate when viewed from above. In some embodiments the block comprises a substantially semi-circular front portion with substantially linear wings extending substantially tangentially to the circumference of the semi-circular portion. In some embodiments the plate  602  is substantially flat and extends perpendicularly to the outside plate  608 . In some embodiments the inside plates  618  and  620  are provided adjacent to the inside edge of plate  602  and substantially perpendicular to the plate  602 . The inside plates  618  and  620  and outside plate  608  generally run around the inner and outer periphery, respectively, of the patient&#39;s gums. 
         [0081]    In some embodiments, a port  616  may be provided through the dental block  602 . The port  616  may be used to suction the patient&#39;s mouth, insert tubes for air, nutrition or other needs, or other similar purposes. 
         [0082]    As shown in  FIGS. 3C and 3D , ratchet heads  310  may be attached to rail  610  and used to attach the dental block to the upper and lower jaws of a patient using the various bone screws and other accessories described herein. 
         [0083]    Many different arrangements of the various components depicted, as well as components not shown, are possible without departing from the spirit and scope of the present invention. Embodiments of the present invention have been described with the intent to be illustrative rather than restrictive. Alternative embodiments will become apparent to those skilled in the art that do not depart from its scope. A skilled artisan may develop alternative means of implementing the aforementioned improvements without departing from the scope of the present invention. 
         [0084]    It will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations and are contemplated within the scope of the claims. Not all steps listed in the various figures need be carried out in the specific order described.