Патент USA US2056417код для вставки
oops, 1936. ‘ L. L. BOSWORTH 2,056,41 7 DENTAL INSTRUMENT Filed ‘June_ 28, 1955 , LUTHER LAWRENCE BOSWORTH ' »-INVENTOR BY ATTORN Y 2,056,417 Patented Oct. 6, 1936 UNI TED STATES PATENT OFFIQE 2,056,417 DENTAL INSTRUMENT Luther Lawrence Bosworth, San Diego, Calif. Application Junez-28, 1935, Serial .No. 28,907 6 ‘Claims. This invention relates to a dental ossisector, the primary use of which ‘is to remove .bon-y structure overlying impacted teeth‘ vpreparatory to extracting them. To the dental profession the problem of ‘im pacted teeth is intensely interesting ‘and of great importance. Heretofore only three methods have been employed ‘in the removal ‘of such teeth; (1) the chisel-and mallet, (2) the ‘surgi 10 cal drills; and. (3) the hand pressure ‘cutting in struments. Progress in vdental surgery depends 'as much upon improving the instruments employed as upon improved technique. ‘There :has long been 15 felt a need for improving present instruments in .such a manner as to make it possible to cut bone with less pressure, less ‘exertion, and less trau matization (of tissue. Also ‘to shorten the time required for operations thus lessening the shock '20 to the patient. By this invention an instrument is provided whereby an improved ‘and radically different method of operating upon impacted teeth is .ren dered possible, but the use of the invention is by 25 no means con?ned to impacted teeth. Instru ments constructed according to the principles of this invention are applicable anywhere in the mouth, and when badlycurved or exostosed roots are found the tooth can be removed ‘intact after 30 these instruments have been used to remove the obstructing tissues. Among the objects attained and advantages securedby the use of the instru ment furnished by this invention may be men tioned the following: Local anaesthesia may be used for all types of impactions; a safer control of instruments is ensured; the operatorcan see the ?eld of operation at all times; bony tissure can be more easily ‘removed; very little pressure is required when cutting away the ‘bony struc 40 ture; less cutting is necessary; ease of operation results with less shock to the patient; there is less trauma and a more rapid recovery; and "there is afforded to the operator greater ease and dis patch in the removal of impacted teeth. Other objects, advantages and features of in 45 vention may hereinafter appear. Referring to the accompanying drawing, which illustrates what is at present deemed to be a preferred embodiment of the invention, 50 Fig. 1 is a perspective view of the complete instrument. Fig. 2 is a transverse section, on an enlarged scale, thru the applicator portion thereof, on line 2-2 of Fig. 1. Fig. 3 is a vertical section of the applicator 55 (Cl. 32-—46) portion, the plane of section ‘being indicated by the line 3-~3 on Fig. 12. Fig. .4 is 1a side elevation illustrating the posi tion of‘ one of the instruments in an operative situation within the mouth of 'a‘ipatien't, the root I of thetooth ibeingoperated upon and those of adjacent teeth being shown in dotted lines, an other of the instruments ‘being ‘similarly shown in ‘readiness to perform the second stage of "the operation. To Fig. 75 is a 'view like Fig. 4 except that other types of instruments, constructed according to the ‘principles of the invention‘ are illustrated "and positioned for di?‘erent cutting operations. ‘Fig. 6 is a side elevation outlining diagram .15 matically the ‘applicator portions of a set of in~ struments ‘differing ‘in design but (all constructed in vaccordance with the invention. Referring ‘in detail to the drawing, the appli cator portion 5 of the instrument ‘designed as 1220 shown-in Figs..1,»2:and-8 is of va somewhat vwedge sh'a-ped character and has, extending lengthwise of its face a ‘plurality of longitudinal, angular vcutting ridges or blades. By preference and as :shown, ‘these cutters consist of a prominent central "cutter '6, and outer cutter ‘I at each ‘side and ‘a ‘cutter 8 at each side between an outer-‘cut ter 1 and the central tooth 16.’ ' The applicator :portion \5 is joined by means of :an offset neck 11 ‘to a diametrically reduced 1. 30 portion ‘I2 of the tool shank ‘l3,'th'ere preferably being a de?nite annular shoulder l4 between'the shank‘ portions 12 and 1.3. A transversely ‘ex tending handle 15 “having 1a fluted ‘central portion [6 is secured to the outer end of ‘the shank 1T3. Describing more in ‘detail the applicator or cut ting portion '5 of ‘the instrument, said ‘portion, as viewed in transverse section, is somewhat convex and preferably smooth along its back side I1, and its opposite side or face is of a serrated, generally 1:40 convex shape, the side portions being chamfered or ?attened at l8. Owing to the downwardly tapering character of the cutting portion '5, each of the ?ve angular cutting ridges thereof, which operates as a knife upon the bone with a shear 45 ing action, diminishes downwardly in its cross sectional extent. The central cutting ridge 6 is shown as substantially right angled in cross sec tion, the a greater or less degree of angularity could be used without departing from the spirit 50 of the claimed invention. The cutter ridges ‘I and 8 at each side of the center each have their faces disposed to each other at less than a right angle as viewed in cross section, and perform their cutting or shearing action when the too} 65 2. 2,056,417 is rocked as indicated by the arrows above Fig. 2. That is to say, the right hand cutters ‘l and 8 cut when the tool is rocked towards the left, and applicator portion which extend lengthwise there the corresponding left hand cutters act when the tool is rocked in the opposite direction. of and progressively diminish in their cross sec tional extent away from that end of the applicator oppositely disposed inwardly directed converging cutting ridges occupying one side or face of said Fig. 4 shows the operative relation of the in- ‘ portion which is joined to the aforesaid shank, strument in relation to an impacted molar tooth 20 to remove the obstructing portion of the bony structure at one side of the crown of the offend 10 ing tooth to permit the proper application of an elevator thereto. In removing the bony tissue the face of said applicator portion which is oc cupied by said cutting ridges being of a generally convex character as viewed in cross section. 2. A tool of the kind described having an appli cator portion with outwardly convexed opposite as stated the instrument is operated by a rocking faces and a set of converging cutter ridges extend movement during which its cutting surface mayv ing longitudinally of one of said faces, the cutter be either directed away from or towardthe tooth 15 to be elevated, while its smooth back surface is edges at each side of the medial portion of said applicator portion being directed toward the mid always directed towards the adjacent tooth, ,width thereof. This manner of operating the instrument pre vents the tooth not being removed from having its enamel injured. 20 ' The various cutting ridges of the instrument are bone knives with their cutting edges- arranged to operate in both directions so as to produce the greatest cutting efficiency. The bone is cut or sheared from three surfaces, right, left and in front when either a right or left motion is em ployed, the rocking movement usually being thru an angle of ninety degrees. . In Fig. 5 the letter Z) designates the type of instrument used at the beginning of an excavat ing operation, and (1 shows the position of an other instrument substituted for the ?rst in order that this operation may be satisfactorily com pleted, thereby providing a clearance above and behind the impacted molar, so that it can be raised and extracted. Altho the invention is illustrate-d in the draw ing in an operative relation to impacted teeth, yet it is to be understood that it has a wide range of use in other situations for cutting bone when bone surgery is indicated. In Fig. 6 is shown a representative set of in struments constructed according to the princi ples of the invention. These instruments are lettered, from left to right, a, b, c, d, e‘ and a’, the 45 instruments a and a’ differing from each other only in that one is for right, and the other for left hand use. Figs. 4 and 5 illustrate the use of in struments a’, b, d and e. The instrument shown in Figs. 1, 2 and 3 is of a still different design. In Fig. 6 the letter 12 is applied to the applicator 50 portion of each instrument to designate the toothed or cutting face thereof. So long as the general shape and arrangement of the cutting or shearing elements remain within the scope of the appended claims, various details thereof may be changed, as skilled workmen may desire, without departing from the spirit of the invention. I claim: 1. An instrument of the kind described having an applicator portion which tapers from one end to the other, and a shank joining the larger end of said applicator portion, there being a set of 15 3. A tool of the kind described having an appli cator portion with convexed opposite faces and a plurality, of angular cutter ridges or blades ex tending lengthwise and slantingly of one of said 20 faces, there being a central cutting ridge which runs longitudinally of the axis of the tool and projects farther than the others, and the slanting cutters at each side of said central cutter substan tially converging to a point and having their 25 cutting edges directed towards said central cutter. 4. In an instrument of the kind described, an applicator portion having two oppositely disposed faces each of a convex character, said instrument having a shank portion united to one end of said‘ 30 applicator portion, that end of said applicator portion being the largest and said applicator por tion tapering toward its opposite or outer end, and there being a set of correspondingly tapering bone cutting knives or ridges extending length 35 wise of one of said convex faces, said knives in cluding a relatively large central knife which shears when the tool is rocked towards either side and cutting knives at each side thereof whose cutting edges are directed towards said central 40 knife. ' ' 5. A tool of the kind described, said tool having an applicator or cutting portion comprising two oppositely disposed faces each of which converge toward .a common point, one of said faces con 45 stituting a front face and the other constituting a rear face, each of said faces being of a convex character with the rear face of less convexity than said front face, said front face having a plurality of converging cutters at each side of the medial portion of said' applicator which are directed toward the mid-width of the tool. 6. In an instrument of the kind described, an applicator portion having two oppositely disposed faces of diverse convexities, said instrument 55 having a shank portion united to one end .of said applicator portion, that end of said applicator portion being the largest and said applicator por tion tapering towards its opposite end, and a plurality of correspondingly tapering inwardly 60 directed knives on one of said faces. LUTHER LAWRENCE BOSWORTH. '