Abstract:
A gauge system for measuring underbite and overbite in ruminants includes a handle having a spring biased retainer pivotally mounted thereon and a head portion at a front end having a tip receiving aperture, a set of interchangeable underbite measuring tips for use with cattle, a set of interchangeable underbite measuring tips for use with sheep, and a overbite measuring tip. The rear portion of the tip retainer is depressed by a user&#39;s thumb to pivot the front portion of the tip retainer upwardly to an open position and expose the tip receiving aperture for insertion or removal of a selected underbite measuring tip, or the overbite measuring tip, and thereafter removing the thumb allows the front portion of the tip retainer member to be lowered under spring pressure to the closed position and retain the selected underbite measuring tip, or the overbite tip in the aperture.

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims priority of U.S. Provisional Application Ser. No. 62/155,452, filed Apr. 30, 2015, the pendency of which is extended until May 2, 2016 under 35 U.S.C. 119(e)(3). 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to instruments for determining jaw defects in animals, and more particularly to a gauge system for measuring underbite (brachygnathia superior) and overbite (brachygnatia inferior) in ruminants. 
     2. Background Art 
     All species of ruminants lack top incisors. All these animals have a tough dental pad below their top lip, sometimes referred to as the maxillary pad, instead of front teeth, and a huge gap between the dental pad (maxillary pad) and the back teeth Underbite (brachygnathia superior) and overbite (brachygnatia inferior) in ruminants are well know genetic jaw defects that develop as a result of several factors, including osteogenetic disorder, mechanical factors and heredity, and is characterized by failure of the premaxillary bone to grow to normal length and width. 
     A normal bite is known as the condition, when the mouth is closed in a bite position and the upper and lower jaw are perfectly aligned, the upper edge of the teeth crown (the part of a tooth external to the gum) is touching the front edge of the dental pad (maxillary pad) of the upper jaw. 
     Underbite (brachygnathia superior), also known as mandibular prognathism, although the first term is considered most correct, is a condition caused by failure of the premaxillary bone to grow to normal length and width. Prognathism refers to a protruding jaw. It is also called an extended chin. In this condition, when the mouth is closed in a bite position, the upper edge of the teeth crown is disposed forward of the front edge of the dental pad (maxillary pad) of the upper jaw. 
     Overbite (brachygnathia inferior), also known as mandibular brachygnathia, and commonly called parrot mouth prognathism, is a condition caused by failure of the anterior of the lower jaw forward of the premolars to grow to normal length, causing an abnormal shortness of the lower jaw. In this condition, when the mouth is closed in a bite position, the upper edge of the teeth crown is disposed rearward of the front edge, or anterior angle, of the dental pad (maxillary pad) of the upper jaw. 
     These jaw defects can lead to serious economic loses in bovine and sheep production systems, because it can seriously affect the grazing animal&#39;s ability to bite off foliage and have adequate nutrition. 
     Therefore it is important to be able identify and quantitatively measure these specific jaw defects in animals in order to select and eliminate those that have this problem, and also to have the ability to quantify the prevalence of underbite (brachygnathia superior) and overbite (brachygnatia inferior) in the animal population. 
     There are several patents directed toward gauge instruments for measuring various dental conditions. The following are several examples. 
     Rhein, U.S. Pat. No. 1,327,114, discloses an attachable or permanent depth gauge which is used with dental and medical instruments to for example, measure the length of a root canal. The gauge disclosed has two members, the first member being affixed or attached to the handle of the instrument and the second member being movable with respect to the first. Depth is measured by viewing an indicator which reflects the distance between the second member and the extremity of the instrument. The sliding gauge must be positioned to the zero point before the measurement is taken and the instrument must be removed from the patient&#39;s mouth in order to read the scale. Mayer et al. U.S. Pat. No. 4,997,368, discloses an oral measuring insert device having biased top and bottom surfaces which can be directed into the mouth between the frontal upper and lower teeth to measure the opening of the mouth. The device is formed from a lightweight, disposable plastic having arcuate grooves positioned within the upper and lower surfaces providing detents for the teeth. Numerical indicia is disposed along the side of the insert to allow the examiner to quickly determine the degree of movement the mandible has undergone at maximum insertion. Various sizes of the insert may be manufactured and made available for different mouth sizes such as for example with young children, older children or adults. 
     Sheridan, U.S. Pat. No. 5,044,951, discloses a dental space and periodontal cavity measuring instrument for insertion in interdental or interproximal spaces between teeth and in periodontal cavities in both the upper and lower dental arches to determine the width of such spaces and the depth of the cavities, respectively, for appropriate treatment. The dental space and periodontal cavity measuring instrument has a centrally located handle provided with a pair of oppositely-extending single tips or multiple, elongated, graduated cylinders which terminate in graduated ends, for insertion in the interdental spaces and periodontal cavities. The calibrated cylinders and graduated ends may be extended in a straight line from the handle, or one or more cylinders in one or both of the calibrated and graduated tips may be angulated and the diameter of each cylinder may be indicated on the handle for size-identification purposes. The ends of the cylinder or stem tips may also be “waffled” with striations for ligature tucking purposes. 
     Urban, U.S. Pat. No. 5,676,544, discloses an instrument for subgingival scaling, root planing and maintenance of periodontal health. The instrument has an elongated body with a handle portion, a terminal shank portion, a working end, and a gauge. The terminal shank portion includes a base having a first portion, which is coaxial with the handle portion, and a second portion, which is angled from the first portion. The working end has a rear heel portion adjacent to the second portion and a front toe portion. Between the heel and toe there is a blade edge extending lengthwise. The gauge is arranged along the annular surface of the second portion of the terminal shank. In order to measure the periodontal health of the patient on whom the instrument is being used, the instrument is inserted into the periodontal space between the tooth and the gum. The depth of the periodontal space is determined by reading the marking on the gauge which meets the gumline. 
     SUMMARY OF THE INVENTION 
     The present invention overcomes the aforementioned problems and is distinguished over the prior art in general, and these patents in particular, by a gauge system for measuring underbite (brachygnathia superior) and overbite (brachygnatia inferior) in ruminants. The gauge system includes a handle member having a retainer member pivotally mounted thereon, a set of interchangeable cow underbite measuring tips for use with cattle, a set of interchangeable sheep underbite measuring tips for use with sheep, and an overbite measuring tip. 
     The handle member has a handgrip portion to be gripped by a hand of a user and a head portion at a front end having a tip receiving aperture. A spring biased tip retainer member is pivotally mounted on the handle member to be pivoted between a normally closed position and an open position, and has a front portion configured to enclose said tip receiving aperture in the closed position and a rear portion configured to receive the thumb of the user&#39;s hand. Each of the underbite measuring tips has a rear portion configured to be removably received in the tip receiving aperture and a front portion having a flat rectangular measuring leg that extends perpendicularly downward from the rear portion. The flat measuring leg of each of the underbite measuring tips has a different thickness of a standard unit of measurement that ranges from 2 mm to 8 mm, respectively. The overbite measuring tip has a rear portion configured to be removably received in the tip receiving aperture and a front portion having a vertical leg portion and a horizontal flat rectangular measuring leg that extends forward and perpendicular thereto and terminates at an outer end. The top surface and lateral sides of the flat rectangular measuring leg has a metric scale divided into millimeters with major markings at 5 mm, 10 mm, 15 mm, and 20 mm beginning at the outer end. 
     The tip retainer member rear portion is depressed by the user&#39;s thumb to pivot the front portion of the tip retainer member upwardly to the open position and expose the tip receiving aperture for insertion or removal of a selected underbite measuring tip, or the overbite measuring tip, and thereafter removing the thumb allows the front portion of the tip retainer member to be lowered under spring pressure to the closed position and retain the selected underbite measuring tip, or the overbite tip in the aperture. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS. 1A and 1B  are perspective views of the gauge apparatus in accordance with the present invention with an interchangeable underbite measuring tip installed in the handle member and retained by the retainer member, shown from the front and rear respectively. 
         FIGS. 2, 3, and 4  are a side elevation view, top plan view, and a front end elevation view, respectively, of the gauge apparatus in an assembled condition. 
         FIG. 5  is a longitudinal cross sectional view of the gauge apparatus taken along line  5 - 5  of  FIG. 3  with a sheep underbite measuring tip retained in the handle member. 
         FIG. 6  is a partial longitudinal cross sectional view of the gauge apparatus, similar to  FIG. 5 , showing a cow underbite measuring tip retained in the handle member. 
         FIG. 7  is a longitudinal cross sectional view taken through the pivot point along line  7 - 7  of  FIG. 4  showing a cow underbite measuring tip retained in the handle member. 
         FIG. 8  is a side elevation view of the handle member. 
         FIGS. 8A and 8B  are perspective views of the handle member shown from the front and rear, respectively. 
         FIGS. 9A and 9B  are perspective views of the retainer member shown from the front and rear, respectively. 
         FIGS. 10 and 11  are a side elevation view and a front end view of the retainer member, respectively. 
         FIG. 12  is a cross sectional view of the retainer member, taken along line  12 - 12  of  FIG. 11 . 
         FIGS. 13A and 13B  are perspective views of a sheep underbite measuring tip shown from the front and rear, respectively. 
         FIGS. 14, 15, and 16  are a side elevation view, a top end view, and a rear end view of the sheep underbite measuring tip, respectively. 
         FIGS. 17A and 17B  are perspective views of a cow underbite measuring tip shown from the front and rear, respectively. 
         FIGS. 18, 19, and 20  are a side elevation view, a top end view, and a rear end view of the cow underbite measuring tip, respectively. 
         FIGS. 21A and 21B  are perspective views of an overbite measuring tip shown from the front and rear, respectively. 
         FIGS. 21C and 21D  are a side elevation view and a top end view of the overbite measuring tip, respectively. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings by numerals of reference, there is shown in  FIGS. 1A, 1B, 2, 3, 4, 5, and 6 , an embodiment of a gauge system for measuring underbite (brachygnathia superior) and overbite (brachygnatia inferior) in ruminants. 
     The major components of the gauge system include a handle assembly  10 , which includes a generally rectangular handle member  11  having a retainer member  20  pivotally mounted on the handle member, a set of seven interchangeable underbite measuring tips  30  for use with cattle (hereinafter referred to as “cow tips  30 ”, and a set of seven interchangeable underbite measuring tips  40  for use with sheep (hereinafter referred to as “sheep tips  40 ”, and a one overbite measuring tip  50 .  FIGS. 1A, 1B, 2, 3, 4, and 5 , show a selected sheep tip  40  retained on the handle member  11  by the retainer member  20 , and  FIGS. 6 and 7  show a selected cow tip  30  retained on the handle member. 
     Referring additionally to  FIGS. 8, 8A, and 8B , the handle member  11  has a rear hand grip portion  12  which can be gripped with the right or left hand of a user with opposed arcuate curved top and bottom surfaces  12 A and  12 B for receiving the hand and fingers of the user, and a head portion  13  at the front end of the handle member adjoined thereto by an intermediate portion  14  of reduced height. The head portion  13  and the intermediate portion  14  extend angularly downward and forward from the hand grip portion at a slight angle relative to a horizontal axis. 
     The top end of the head portion  13  has an outwardly and downwardly curved rear portion  13 A that adjoins the top of the intermediate portion  14  and has a front end portion  13 B of narrower width. A raised rounded boss  15  is formed on the top surface of the intermediate portion  14  adjacent to its juncture with the hand grip portion  12 . A hole  13 C extends transversely through the head portion  13 , and a slot  16  extends transversely through the head portion  12  disposed forward of the hole  13 A which is configured to slidably receive a selected cow tip  30  or sheep tip  40  from either side of the slot. The slot  16  has an open front end, a flat bottom surface, a semicircular rear end, and a top surface that has a first upwardly curved larger radius rear cavity  16 A adjoining the semicircular rear end, and an adjacent second upwardly curved smaller radius front cavity  16 B spaced a short forwardly therefrom. 
     Referring additionally to  FIGS. 9A, 9B, 10, 11, and 12 , the retainer member  20  has a generally inverted U-shaped configuration with an arcuate slightly curved top wall  21  and a pair of laterally opposed side walls  22  that are slidably received on, and straddle, the head portion  13  of the handle member  11 . A rounded boss  23  is formed on the underside of the top wall  21  near its rearward end, and a pair of parallel closely spaced tabs  22 A are formed on the interior surface of each side wall  22 , respectively, near their front ends and extend a short distance inwardly from the side walls in opposed relation and terminate a distance from the side walls to define an interior space therebetween. When the retainer member  20  is mounted on the handle member  11 , the tabs  22 A are slidably disposed on opposed outer sides of the narrower width portion  13 B at the top end of the head portion  13  of the handle member and straddle the laterally opposed open ends of the second upwardly curved smaller radius front cavity  16 B. A hole  22 B is formed in each of the laterally opposed side walls  22  in axial alignment. 
     The retainer member  20  is pivotally mounted on the handle member  11  by passing the shank of a clevis pin  50  through the axially aligned holes  13 A and  22 B in the handle member and the sidewalls  22  of the retainer member  20 , and installing a cotter pin  51  through a hole in the outer end of the clevis pin shank. 
     As best seen in  FIGS. 5 and 6 , a compression spring  70  is mounted between the handle member  11  and the retainer member  20  by engaging one end of the spring on the rounded boss  15  on the top surface of the intermediate portion  14  of the handle and its opposed end on the rounded boss  23  on the underside of the top wall  21  of the retainer member  20 . The compression spring  70  urges the retainer member to a normally closed or retaining position wherein the rear portion of the retainer member is pivoted to a raised position and the lower front portion of its lateral sidewalls  22  straddle and enclose the lateral sides of the head portion  13  of the handle member  11  and the slot  16  and its larger radius rear cavity  16 A and smaller radius front cavity  16 B. 
     The retainer member  20  is moved to an open position by a user gripping the hand grip portion  12  of the handle  11  in their hand, placing their thumb on the top surface at the rear of the retainer member, and pressing downward until the bottom surface of the front portion of the retainer member is raised to expose the lateral sides of the head portion  13  of the handle member and the slot  16  with its larger radius rear cavity  16 A and smaller radius front cavity  16 B. 
     As mentioned briefly above, the gauge system includes a set of seven interchangeable underbite measuring tips  30  for use with cattle (hereinafter referred to as “cow tips  30 ”, and a set of seven interchangeable underbite measuring tips  40  for use with sheep (hereinafter referred to as “sheep tips  40 ”, and a one overbite measuring tip  60 . FIGS. A,  1 B,  2 ,  3 ,  4 , and  5 , show a selected sheep tip  40  retained on the handle member  11  by the retainer member  20 , and  FIGS. 6 and 7  show a selected cow tip  30  retained on the handle member. 
     Referring additionally to  FIGS. 13A, 13B, 14, and 15 , each of the underbite measuring cow tips  30  is a generally inverted L-shaped configuration having a semi-circular rear portion  31  sized and shaped to be slidably received in the larger radius rear cavity  16 A of the slot of the head portion  13 , and an adjoined smaller rectangular intermediate portion  32  that is sized and shaped to be slidably received in the slot  16  of the handle member  11  from either lateral side of the handle member. The smaller rectangular portion  32  of each underbite measuring cow tip  30  adjoins a larger rectangular portion  33  which is sized and shaped to engage the flat front end of the head portion  13  of the handle member when the interchangeable tip is installed the slot. A flat rectangular measuring leg  34  extends perpendicularly downward from the front end of the larger rectangular portion. The thickness TC of the flat rectangular measuring leg  34  is different for each one of the seven underbite measuring cow tips  30 . More particularly, the thickness TC of each of the underbite measuring cow tips  30  is of a standard unit of measurement that ranges from 2 mm to 8 mm, respectively. As seen in  FIG. 14 , each of the underbite measuring cow tips  30  may be provided with a numeral  35  on each side of the larger rectangular portion that corresponds to the respective unit of measurement. 
     Table 1 below illustrates an example of a numbering system that may be utilized for easily and quickly identifying the respective underbite measuring cow tips  30 . 
     
       
         
               
               
             
               
               
               
             
           
               
                 TABLE 1 
               
             
             
               
                   
               
               
                 COW TIP 
                 THICKNESS “TC” 
               
             
          
           
               
                 NUMERAL 
                 MM 
                 INCH 
               
               
                   
               
               
                 2 
                 2 
                 .079 
               
               
                 3 
                 3 
                 .118 
               
               
                 4 
                 4 
                 .157 
               
               
                 5 
                 5 
                 .197 
               
               
                 6 
                 6 
                 .236 
               
               
                 7 
                 7 
                 .275 
               
               
                 8 
                 8 
                 .315 
               
               
                   
               
             
          
         
       
     
     Referring additionally to  FIGS. 17A, 17B, 18, 19, and 20 , each of the underbite measuring sheep tips  40  is also a generally inverted L-shaped configuration similar to the cow tips, but narrower in width. Each of the underbite measuring sheep tips  40  has a semi-circular rear portion  41  sized and shaped to be slidably received in the smaller radius front cavity  16 A of the slot of the head portion  13 , and an adjoined smaller rectangular intermediate portion  42  that is sized and shaped to be slidably received in the slot  16  of the handle member  11  from either lateral side of the handle member. The smaller rectangular portion  42  of each underbite measuring sheep tip  40  adjoins a larger rectangular portion  43  which is sized and shaped to engage the flat front end of the head portion  13  of the handle member when the interchangeable tip is installed the slot. A flat rectangular measuring leg  44  extends perpendicularly downward outward from the front end of the larger rectangular portion. The thickness TS of the flat rectangular measuring leg  44  is different for each one of the seven underbite measuring sheep tips  40 . More particularly, the thickness TS of each of the underbite measuring sheep tips  40  is of a standard unit of measurement that ranges from 2 mm to 8 mm, respectively. As seen in  FIG. 18 , each of the underbite measuring sheep tips  40  may be provided with a numeral  45  on each side of the larger rectangular portion that corresponds to the respective unit of measurement. 
     Table 2 below illustrates an example of a numbering system that may be utilized for easily and quickly identifying the respective underbite measuring sheep tips  40 . 
     
       
         
               
               
             
               
               
               
             
           
               
                 TABLE 2 
               
             
             
               
                   
               
               
                 SHEEP TIP 
                 THICKNESS “TC” 
               
             
          
           
               
                 NUMERAL 
                 MM 
                 INCH 
               
               
                   
               
               
                 2 
                 2 
                 .079 
               
               
                 3 
                 3 
                 .118 
               
               
                 4 
                 4 
                 .157 
               
               
                 5 
                 5 
                 .197 
               
               
                 6 
                 6 
                 .236 
               
               
                 7 
                 7 
                 .275 
               
               
                 8 
                 8 
                 .315 
               
               
                   
               
             
          
         
       
     
     Because the underbite measuring sheep tips  40  are narrower than the cow tips  30 , they are retained in the smaller radius front cavity  16 A of the slot of the head portion  13  of the handle member by the inwardly facing closely spaced tabs  22 A on the interior surface of each side wall  22  of the retainer member  20  which straddle the lateral sides of the smaller radius front cavity when the retainer is in the spring biased closed position. 
     Referring now to  FIGS. 21A, 21B, 21C, and 21D , the overbite measuring tip  60  is a generally L-shaped configuration having a vertical rectangular leg portion  61  and a horizontal flat rectangular measuring leg portion  62  extending forward and perpendicular thereto. The back side of the vertical leg portion  61  has a horizontal rectangular portion extending a short distance rearwardly therefrom terminating in a semi-circular rear end portion which are sized and shaped to be slidably received in the larger radius rear cavity  16 A of the slot  16  of the head portion  13  of the handle member  11  from either lateral side of the handle member, respectively. When the overbite measuring tip  50  is received in the slot of the handle member, the back side of the vertical rectangular leg portion  61  is disposed against the front end of the head portion  13  of the handle member and the flat rectangular measuring leg portion  62  extends outwardly a distance beyond the front end of the handle member  11 . The top surface and lateral sides of the flat rectangular measuring leg  62  are provided with a metric scale divided into millimeters with major divisional lines  65  at 5 mm, 10 mm, 15 mm, and 20 mm beginning at the outer end of the measuring leg. 
     Tool Assembly 
     To install a selected underbite measuring tip  30 ,  40 , or the overbite measuring tip  50  into the handle member member  11 , the handle is held gripped by one hand (right or left hand) of the user, and the retainer member  20  is pivoted to the opened position by the user&#39;s thumb to expose the slot  16  and its larger radius rear cavity  16 A and smaller radius front cavity  16 B of the head portion  13 . The selected underbite measuring tip or overbite measuring tip is aligned with the slot  16  and cavity  16 A or  16 B and pressed into the slot and cavity from either lateral side of the handle with the user&#39;s other hand. The retainer member is closed by relieving the downward pressure exerted by the user&#39;s thumb such that the front portion of the retainer member covers the slot and rear portion of the underbite or overbite measuring tip installed therein, to releasably secure the selected measuring tip to the handle. 
     When an underbite measuring tip is secured in the handle member, the flat rectangular measuring leg extends downwardly a distance beyond the front end of the handle member. When the overbite measuring tip is secured in the handle member, the flat rectangular measuring leg portion bearing the scale extends forwardly a distance beyond the flat front end of the handle member. 
     These steps are reversed to remove the selected underbite measuring tip or overbite measuring tip from the handle member. 
     Operation 
     After the selected underbite measuring tip or the overbite measuring tip has been secured to the handle, the tool is ready to be used to accurately measure the underbite or overbite condition of the animal depending upon the tip that was installed. 
     It is recommended that at least two people be present in order to make a proper measurement of the animal&#39;s bite; one person that holds and opens the animal&#39;s mouth, and another person that places the tool in the animal&#39;s mouth and measures the bite. 
     The animal is placed in a location where its head can be safely held still in a secure manner, not only for the animal, but also for the safety of the person holding the animal for the person that is using the measuring tool. 
     A muzzle is placed on the animal&#39;s head to immobilize and prevent the animal from moving its head. 
     After the animal&#39;s head is immobilized and with its mouth in a closed biting position, one person places both hands with the fingers facing up and the palm in front of the animal&#39;s lips, then, using their the fingers to open the lips, to make sure the animal stays in a biting position with the mouth closed. 
     Normal Bite Condition 
     With the animal&#39;s lips open and its mouth closed in the bite position, if it is seen that the upper and lower jaw are perfectly aligned, the edge of the teeth or crown should be touching the front edge of the dental pad (maxillary pad) in the upper jaw of the animal, this is considered to be a normal bite condition. 
     Underbite Condition 
     If the crown of the lower teeth is not touching the dental pad (maxillary pad) in the mouth closed, bite position, it means that the animal has an unusual bite or an underbite, and in which case the underbite measuring tips are is used to measure the distance between the back of the teeth and the gum at the top of the edge of the dental pad (maxillary pad). 
     This is accomplished, with the animal&#39;s mouth closed in the bite position and the lips open, by placing the flat rectangular measuring leg of the underbite measuring tip attached to the handle member in the space between the teeth and the dental pad (maxillary pad). In order to achieve an exact measurement, the thickness of the flat rectangular measuring leg of the underbite measuring tip has to fit perfectly in the space between the back of the teeth and the front edge of the dental pad (maxillary pad). Thus, it may require changing the tips until you find the one having the proper thickness (i.e., from 2 mm to 8 mm) to perfectly fit the space between the back of the teeth and the front edge of the dental pad (maxillary pad). This allows the exact measure according to the thickness (millimeter number) of the tip used. 
     Overbite Condition 
     If the crown of the lower teeth touches the dental pad (maxillary pad) behind the anterior angle of the dental pad, it means that the animal has an overbite, and in which case, the overbite measuring tip is used to measure the space between the lower teeth and the anterior angle of the dental pad. This is accomplished, with the animal&#39;s mouth closed in the bite position and the lips open, by placing the overbite measuring tip in the front part of the teeth with the rectangular measuring leg portion extending to the anterior angle of the dental pad (maxillary pad), and reading the scale to determine the distance between the teeth and how far they are from the dental the dental pad (maxillary pad). 
     While the present invention has been disclosed in various preferred forms, the specific embodiments thereof as disclosed and illustrated herein are considered as illustrative only of the principles of the invention and are not to be considered in a limiting sense in interpreting the claims. The claims are intended to include all novel and non-obvious combinations and sub-combinations of the various elements, features, functions, and/or properties disclosed herein. Variations in size, materials, shape, form, function and manner of operation, assembly and use, are deemed readily apparent and obvious to one skilled in the art from this disclosure, and all equivalent relationships to those illustrated in the drawings and described in the specification are intended to be encompassed in the following claims defining the present invention.