CA1284041C - Dental articulator and method - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE

A method and apparatus for recording condylar motion and utilizing such recording in a dental articulator involves the production of three-dimensional solid recordings formed by the patient executing full mandibular motion, and transferring the recordings under conditions of accurate alignment to a dental articulator where they function as bearing surfaces for the precise reproduction of condylar motion.

Description

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TI~L~: D~'~TTAL ARTIC[JL~TOR AND METHOD

~ACI~r,ROIJ~lD o~ T~IE I~ .N~
, This invention relates ~enerally to a dental articulator, and ~ more rarticularly to im~rovements in the counling portions of the articulator and to a metho~ for ac'nie~tin~ said i~prover.ents.
Attempts to develo~ useful instrumentation to follow man~i-¦ bular move~ents througl~ 211 its nositions and excursions aremanifold. ~he ~ovements of the mandihle are three dimensional with riglt and left articular elements ~erformin~ similar or dissimilar movements depenclin~ on anatomical for~. and tile functions ~erformed. ~ince the t~o joints are intercon~ected, j movement in one ~oint will have an effect on its counter~art.
The chief determinants for rebuilding the patient's occlusion ; 15 with fidelity are the recordin~ and transferring of the motions of the mandible from t:~e patient to the ~ental articulator used in such re~uildin~.
Dental articulators fall into ~ive ~eneral cateqories according to function:
a. ~~in~1e hine which opens and closes.
D. ~e~i-adjustable which hin~e.s and also ~erforms ~rotrusiv~
and lateral movements which are quided hy avera~e setting.s.
c. Ad~ustable articulators which utili2e intra-oral ~osi-__ _ _ _ _ _, __ tional jaw records from the patient in centric and eccentric positions to set straiqht line ~uiding i surfaces or cams in the articulator.
d. Adiusta~le articulator~ w h extra-o al ?anto~ anhic tracings in which the entire tracin~.s are used to set -30 ' the a~?pro~riate articulator.

1 2~340Al ! e. Adjustable articulator utilizin~ intra-oral ~olded pathway~ which are then transferred to an articula~or b~
molding condylar pathways in the articulator.
The a~orementioned earlier methods are faultv either in their i inabilit~ to capture the three dimensional as~ects in recordin~
the data or in the ~ani~ulative difficulties with the articu-lator s acceptance of ~he records or in the transfer of the patient s dental ~0~21s to the articulator in pro~er three l dimensional orientation to the records. The customized analogs however aive a closer ap~roxiration to the action of the natient s own mandihular joints than do the mechanicall-~ adjust-ahle joints or those with av~ra~e settinqs.
It is accordin~ly an object of the present invention to I ~rovide an im~roved customized analo~ for reproducin~ the action of a dental ratient s tem~oroman~ibular joints.
It is another object of this invention to ~rovide an analo~
customized for an individual dental ~atient which may be readil~
and simnly a~se~led as a dental articulator to reproduce the motion of the ~atient s temporomandihular ~oints.
Another ob~ect of this invention is to ~rovide an i~roved me~hocl of for~in~ an accurate analo~ of a dental ~atient s temnoromandibular joint.
A further object of the ~resent invention is to provide a method and a~aratus ~or formin~ an analoq of a tem~oromandi~ular 2~ joint and accuratelv relating the ~atient s dental wor~in~ model in the assembly of the dental articulator.
These objects and other objects and advantaqes of the invention will he a~arent from the followin~ descri~tion.

SUMMARY OF T~iE INVENTION
The above and other beneficial ob~ects and advantages are accomplishe~ in accordance with the present invention by a metllod and associated apparatus which construct monolithic three-dimensional bearing surfaces representing condylar path-ways, and pivotably mount said surfaces upon stationary upri~ht condyle bslls in a dental articulator.
The apparatus is comprised of: 1) a maxillary recording assembly adapted to attach to the upper jaw, 2) a mandibular recording as~embly adapted to attach to the lower jaw, 3) an upper articulator member, and 4) a lower articulator member adapte~ to pivotably engage said upper articulator member.
The maxillary recording assembly is comprised of a first rigid U-shaped bow having a straight forward bar and two extremities positioned at eqllal distances rearwardly of said forward bar, box-like receptacles remova~ly attached to said rearward extremities, and an upper bite plate (also known as a clutch) pendantly attaclled to sai(l ~orward bar and displaced rearwardly therefroln.
The mandibular recordlng assembly, adapted to be positioned beneath said maxillary assembly, is comprised of a second rigi~
U-shaped bow haYing a straight forwar~ bar and extreDIities provi~ed with po.sts perpendicularly adjustable with respect to said bow, said posts having affixed to thelr upper extremities a ball made of a polytetrafluoroethylene such as that sold under the trademark "TRFLON", which ball is adapted to enter the recep-tacles of said maxillary assembly. A lower bite plate or clutch is attached to said forward bar in substantially coplanar relation-ship therewith and extending rearwardly therefrom to a position of 3~ vertical alignment with said upper bite plate.
The upper articulator member is comprised of a rigid plate having a centered aperture, equal left and right side arms radiating away from said aperture in a straight line path, and an arm extending forwardly of said aperture in perpendicular dis-position to said side arms. A mounting ring is held to the underside of the plate by a threaded bolt that penetrates said aperture. The distal extremity of said forwardly directed arm holds a vertically adjustable post. The distal extremities of said side arms are provided with means which permit accurate attachment of the aforesaid receptacles.
The lower articulator member is comprised of a horizontally disposed floor plate, a main cross bar supported above the rear extremity of the plate which accommodates vertically positionable left and right Teflon balls adapted to enter the receptacles attached to the upper articulator member, a centrally located threadably attached mounting ring, and an incisal guide table positioned atop the plate adjacent its forward extremity.
BRIEF DESCRIPTION OF T~IE DRAWING
For a fuller understanding of the nature and objects of the invention, reference should be had to the Eollowing detailed description taken in connection with the accompanying drawing forming a part of this specification and in which similar numerals of reference indicate corresponding parts in all the figures of the drawing:
Figure lA is a top plan view of an embodiment of the maxillary recording assembly of this invention.
Figure lB is a bottom view of the maxillary recording assembly of Figure lA.
Figure lC is a front perspective view of the maxillary recording assembly of Figure lA.
Figure 2A is a front perspective view of an embodiment of the mandibular recording assembly of thls invention.
Figure 2B is a bottom view of the mandibular recording assembly of Figure 2A.
Figure 2C is an enlarged top view of the lower bite plate o~ ~

snown in Figure 2A.
Figure 2D is an enlarged fragmentary perspective view of an ¦ ex~remity of the mandibular recording assembly shown in Figure ¦ 2A.
, F~gure 3A is a side view of the interengaged maxillary ¦~ and mandibular recording assemblies illustrating the method of their use.
Figure 3B is a front view of the interengaged recording assemblies of Figure 3A.
ln i Figure 3C is an enlarged fragmentary bottom view of the receptacle components of said maxillary recording assembly as shown in Figure lB, one of said receptacles being shown con-taining a condylar pathway, the other receptacle being shown ' containing an axis orientation pointer.
1 Figure 4A is a top perspective view of an embodiment of an upper articulstor member of the present invention.
Figure 4B is a bottom perspective view of the articulator member of Figure 4A.
Figure 5A is a front perspective view of an embodiment of the I lower articulator member of this invention.
Figure 5B is a rear perspective view of the articulator i member of Figure 5A.
¦~ Figure 5C is a fragmentary rear view of the assembled upper and Iower articulator members showing an optional centric lock I mechanism.
I Figure 6 is a side view showing the manner of transitory ¦ interengagement of the maxillary recording assembly with the upper articulator member.
~ Figure 7 is a side perspective view of the assembled upper ~ and lower articulator members in association with models of the ¦ patient's teeth.

1 For convenience in description, the terms "front" and "rear", '.

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and words of similar import, will have reference to the right and ¦~ left extremities, respectively, of the apparatus as shown in Figure 7. Similarly, the terms "left" and "right" will have reference to the left and right portions, respectively, of the component of the apparatus illustrated in Figure 4A ar.d com-ponents suitably oriented thereto. The expression "interior" or equivalents thereof will in general have reference to the geometric center of the apparatus shown in Figure 7 D~SCRIPTION OF THE PREFERRED EMBODIMENT
Referring to Figures lA, lB, lC and 3A, 3B, 3C of the ¦' drawing, the maxillary recording assembly 64 is shown comprised of a substantially U-shaped first rigid bow 5 having a straight ¦ forward bar 65, and two extremities 66 positioned equidistantly I rearwardly of said forward bar. The bow is bounded at its top, bottom, exterior edge and interior edge by substantially flat surfaces 67, 68, 69 and 70, respectively. Shoulders 76 protrude jl inwardly from interior edge 70 adjacent extremities 66.
¦l Left and right box-like receptacles 4L and 4R, respectively, I are securely but removably fastened to the extremities of bow 5.
I Each receptacle is comprised of a flat upper surface 71, a flat lower surface 72 surrounding a recessed molding cavity 59, flat sidewall edges 73, and an attachment arm 74. The receptacles are attached to bow 5 by means of cap screws 7 which penetrate holes ¦ provided in the bow and engage threaded holes 6 in attachment arm j 74. In such position of attachment, it is to be noted that the ~, attachment arm 74 is in abutment with the interior edge 70 and shoulder 76 of the bow. When ready for use in recording a patient's condylar pathways, the cavity 59 of each receptacle is ' filled with a plastic non-elastic recording clay composition i 30 capable of being hardened with minimal dimensional change.
Suitable compositions include monomers and prepolymers capable of undergoing addi~ional-type polymerization in the presence o~

catalytic species to form solid products. Such compositions, generally referred to as auto-polymerizing materials, may for example contain cyanoacrylate substances polymerizable by peroxide-type free radical catalysts. Such compositions may also 3 incorporate solid powder lubricants such as Teflon, graphite, talc and molybdenum disulfide. In some embodiments, thin plates 23 as shown in Figure 3C, containing a circular indentation 77, may be placed within the molding cavity, their presence being useful as positioning guides for the subsequent recording step.
An orientation pointer 8 of threadably adjustable length may be removably associated with the interiorly directed portion of the sidewall edge 73 of each receptacle, said pointers being directed toward the interior of the bow, and used to position the ¦appnratus upon the patient relative to the patients mandibular condyles. A hardened composition having a condylar tracing or pathway 60 is shown filling one cavity 59 in Figure 3C.
An upper bite plate 9, also known as a maxillary clutch, is ¦¦pendantly attached to forward bar 65 by a slidable fastener 11 and post lO depending therefrom. Movement of fastener ll upon ¦¦bar 65 is controlled by set screw 78.- A support bar 79 extends connectively between the lowermost extremity of post lO and maxillary clutch 9. Such arrangement of components allows for positioning of the maxillary recording bow in horizontal align-ment with the midline of the face and vertically aligned with the Frankfort Plane (axis orbital plane). Said maxillary clutch is upwardly and rearwardly domed. A trough 80 extends about the front and sides of the upper surface of the clutch, said trough being adapted to receive a material such as a paste of zinc oxide and eugenol which forms maxillary tooth imprint 6?. The under-side of the maxillary clutch is comprised of a forwardly disposed upwardly curved bearing surface 57 and opposed substantially flat side portion 58.

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¦ The mandibular recording assembly 81, as shown in Figures 2A, ¦1 2B, 2C and 2D, is comprised of second rigid U-shaped bow 12 ~¦ having s~raight forward bar 82, and rearwardly disposed ¦1 extr mities 83. The bow is bounded at its top, bottom, exterior ~l edge and interior edge by substantially flat surfaces 84, 85, 85 ij and 87, respec~ively. A smooth bore circular cylindrical channel Il 88 is perpendicularly disposed to said top and bottom surfaces ¦¦ a~jacent extremities 83. A cylindrical post 13 is adapted to l slidably engage channel 88. The uppermost extremity of said ¦ post, located above top surface~84, i8 provided with an attached Il ball 149 preferably fabricated of Teflon material. The posi~ion !1 of the ball above said top surface is fixed by cap screw 16 which penetratively engages a threaded channel communicating I horizontally between outside surface 86 and channel 88. The balls are spaced in a manner to enter the respective receptacles of the overlying maxillary recording assembly.
A lower bite plate or clutch 19 is attached by extension bar 21 and slidable fastener 22 to forward bar 82 in substantially I coplanar relationship therewith and extending rearwardly ~here-¦¦ from to a position of vertical alignment with said upper bite ¦I plate. The underside of bite plate i9 is provided with a U-shaped trough 100 adapted to receive an imprint paste such as that used in upper bite plate 9. A vertically adjustable bearing I stud 20, extending upwardly from the substantially flat upper Ij surface 89 of said bite plate, is centered within the ~agittal 1 plane represented by dashed line 90, and is adapted to engage thè
¦I curved forward bearing surface 57 of said upper bite plate. An ¦I L-shaped guide pin 17 i9 slidably engaged by channel 91 in close ¦I parallel juxtaposition to channel 88. A threaded lock bolt 18 ¦I penetrates an edge of the bow to fix the position of pin 17 ¦ within its channel. The function of guide pins 17 is to aid in ¦ the proper positioning of balls 14 when the receptacles are ~8~

filled with the recording material.
Upper articulator member 92, as shown in Figures 4A, 4B and 7, is comprised of rigid base plate 24 having flat upper and lower surfaces 93 and 94, respectively, a boundary sidewall 95, and a penetrating bolt 25 centered in said sagittal plane and extending beneath lower surface 94 and perpendicular thereto.
Opposed equal right and left side arm portions 2~ and 29, respectively, extend away from the sagittal plane in a straight ;~ line path. A forward arm portion 34 extends from said bolt in ~ centered relationship to the sagittal plane and in perpendicular disposition to said side arm portions. A mounting ring 27 is held tightly to lower surface 94 by bolt 25. The forwardmost or distal extremity of arm 34 holds vertically adjustable post 2 whose position is locked by constricting collars 35 or equivalent means.
The distal extremities of side arms 28 and 29 are provided with penetrative threaded bolts 31 adapted to extend below lower surface 94 and into engagement with holes 22 in upper surface 71 of attachment arm 74 of the corresponding receptacles 4L and 4R.
In some instances, a spacer block 32 may be inserted between the lower surface of the side arm portions and the underlying receptacle to provide adequate space for mounting the patient's maxillary model. By virtue of the aforesaid arrangement of com-~ ponents, the receptacles are adapted to be transposed from the 2~ maxillary recording assembly into the upper articulator member;
and during said transposition the receptacles are secured to both the maxillary recording assembly and upper articulator member. Base plate 24 of said upper articulator member may be further provided with a rear extension 36, the underside of which ~ supports paired pivot pla~es 37 held by bolts 40 which extend through channels 38 and into threaded recesses 39.
Lower articulator member 96, as shown in Figures 5~, 5B, 5C, ~Z8~

and 7, is comprised of horizontally disposed floor plate 43, the underside of which is provided with one forward and two rearward adjustable bolt footings 55 and 56, respectively. Posts 44 support main cross bar 45 above the rear of said floor plate in parallel relationship therewith and perpendicularly disposed to the sagittal plane. Left and right balls 14 atop posts 13 are vertically positionable above cross bar 45 by virtue of sliding engagement of posts 13 within close-fitting channels 46. Set screws 50 lock posts 13 within channels 46. Said post and ball combinations are preferably identical to those earlier described with respect to mandibular recording assembly 81. The lateral and vertical positioning of the balls is such as to facilitate engagement with condylar moulded pathways 60 within overlying cavities 59.
A lower mounting ring 48 is held fast upon the upper surface of floor plate 43 by centered mounting bolt 52 acting from the underside of said floor plate, Said mounting ring facilitates attachment of the patient's mandibular model 54 as shown in Figure 7. A positioning stud 53, rising upwardly from said floor plate, engages mounting ring 48 to ensure precise positioning of the ring and model 54 mounted thereupon. An upraised platform 3 having a flat upper surface is positioned upon floor plate 43 adjacent its forward extremity. The upper surface of said platform serves as abutment means for the lowermost extremity of adjustable post 2 of said upper articulator, as shown in Figure 7. The upper surface of the platform may alternatively be contoured to have angular indentations or a custom molded configuration produced from a clay-like composition comprised of ~ autopolymerizing resin. It is to be noted that the upper extremity of post 2 is shown to have a curvsture representing an arc of a circle centered upon a line drawn between the centers of balls 14. Such configuration ensures that, despite vertical I

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adjustments of the post, its lowermost extremity will remain in the same position upon said platform.
A pivot post 1 is rotatably held by bearing block 97 slide-! ably positioned upon cross bar ~5. The rotative position of the post is ixed by set screw 98. Movement of the bearing block along cross bar 45 is fixed by set screws 51. The pivot post is adapted to be embraced by pivot plates 37 pendant from the upper articulator member.
A channel 99 penetrates said pivot post in a horizontal direction at a height above said cross bar defined by a line drawn between the centers of the balls. A pivot pin 42 remov-ably extends through said pivot plates and the channel in said pivot post. Such assembly constitutes optional means for pivotably interengaging the upper and lower articulator members lS so that movement of the upper member toward or away from the lower member is restricted to motion in a vertical path. The pivotal plates 37 are secured to plate 36 in their rearmost part so that they may be loosened and turned out of functional use subsequent to removal of axis pin 42.
In the method of this invention, the maxillary and mandibular clutches 9 and 19, respectively, are fabricated either intra-orally or on a conventional hinge type articulator. The facing surfaces of the clutches are adjusted and polished so that ; b~aring post 20 contacts the curved forward portion of the underside of the maxillary clutch, and the peripheral areas of the facing surfaces have smooth simultaneous contact, thereby preventing rocking of the clutches about the bearing post.
The bows are positioned so that balls 14 are seated within ~ the depressions 77 of plates 23 located within cavities 59. The positions of the balls are then adjusted such that there will be no contact with the cavity walls in all possible movements. In such positioning adjustments pointers 8 may be used to secure ~z~

precise orientation with the condyle axes, thereby providing greater fidelity of the molded pathways to the actual movements i of the patient's condyles. Plates 23 and said pointers are then ll removed, and the cavities are filled with recording clay. The clutches are then cem~nted to the maxillary and mandibular teeth of the patient using a paste of zinc oxide and eugenol.
The balls are manually seated into the cavities 59 filled with the aforesaid hardenable clay-like plastic composition until 1 the original preclay position of the Teflon balls is achieved.
Said preclay position is located using the L-shaped pins 17 located on the mandibular bow, said pins functioning as depth gauges. The balls, now in contact with the plastic composition, function as forming balls.
' As shown in Figures 3A and 3B, the patient begins molding the 15 I condylar pathway, starting from the most retruded mandibular position. The patient is asked to protrude and retrude his lower jaw and subsequently to perform right and left lateral mandibular movements. Such action produces three-dimensional impressions of ll' said motion. The impressions mag be added to and lubricated and 20 ¦I re-inserted for achieving the most accurate result. After finely detailed, accurate condylar pathways 60, as shown in Figure 3C, have been established and hardened to constitute stable solid recordings, the maxillary and mandibular recording assemblies are ~I removed from the patient. The aforementioned procedure allows ~ for diagnostic visual observation of the reproduced condylar 1~ pathways which yields additional information about the synchrony il or asynchrony of the condylar movements as well as the timing of the movement in each condyle for each basic movement. These I¦ observations allow the operator to simulate these movements 30 1l during dental fabrication procedures. This arrangement also allows ~or three dimensional analysis of condylar pathways.

In the mounting procedure, the patient's maxillary model 61 I!
l l is qeated in the zinc oxide and eugenol paste imprints 62 in maxillary bite plate 9. The base plate 24 of the upper articulator member with attached mounting ring 27 is next secured -- to the box like recepticles 4R and 4L of the maxillary recording , apparatus. This is accomplished utilizing cap screws 31 which penetrate spacers 32 and engage holes 22 in the upper surface 71 of the receptacles. By virtue of such procedure, the maxillary bow is directly transformed in~o an upper articulator member.
~ The patient's maxillary model is next affixed to the mounting ring 27 of the upper base plate 24 utilizing dental mounting plaster. In such manner of association the teeth of the patient's model 61 seat within the imprint 62 of the upper bite plate 9 and is secured to upper mounting ring 27.
Cap screws 7 are then removed, a procedure which permits ~ removal of first bow 5, with attached upper bite plate which is then set aside. This procedure ensures complete fidelity in the orientation of the patient's maxillary model 61 to the molded condylar pathways 60 and further ensures that the mounted models in the articulator have the same occlusal plane inclination relative to the Frankfort Plane as the patient's jaws have in the head. If methods other than this direct one are used, serious orientation errors could result. The aforesaid procedure essentially converts the maxillary recording assembly into an upper articulator member~ with the patient's maxillary model 61 mounted and accurately oriented to the molded condylar pathways 60. It is to be noted that the apparatus component heretofore referred to as the upper articulator member is in actuality merely a precursor of the completed member.
Subsequently, the upper articul`ator member with the mounted maxillary model and condylar pathways is placed on the Teflon balls 14 of the lower articulator member as shown in Figure 7.
Since the medio-lateral distances of the Teflon balls 14 in the ~8~~

mandibular recording apparatus and the Teflon balls in the lower articulator member are identical, the upper condylar pathways fit accurately to the lower Teflon articulator balls which now function as tracing balls. Since the balls are in the most superior position in the clay paths in the centric relation jaw " position, the orientation of the balls to this position is very easy and very stable. With upper and lower articulator members in proper interengagement and held in place with elastics over the receptacles containing the condylar pathways, the patient's i mandibular model 54 is mounted to the lower articulator member utilizing an interocclusal record 63, as shown in Figure 7. The assembled articulator by virtue of its specialiæed features, ¦l requires no centric lock for patients with normal condyles. Said Il interocculusal record is composed of a stiff wax and zinc oxide ~1 and eugenol paste and taken in centric relation position. This 1l completes the mounting of the patient's models in proper ¦ relationship to the condylar pathways. The assembled articulator is capable of accurately reproducing condylar and mandibular __~ ¦ motion in its entire merge as well as opening and closing, ¦I without deviation, on the same radius of the arc of closure as the patient in the retruded condylar position.
While particular examples of the present invention have been ' shown and described, it is apparent that changes and modifications may be made therein without departing from the ~j 25 ¦il invention in its broadest aspects. The aim of the appended ;I claims, therefore, is to cover all such changes and modifications ¦ as fall within the true spirit and scope of the invention.

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Claims (10)

1) A method for forming a recording of the condylar motion of a dental patient and utilizing said recording for recon-structive purposes using a dental articulator having inter-active upper and lower members, said method comprising:
a) having the patient bite down upon slidably abutting bite plates affixed to maxillary and mandibular recording assemblies, one of said assemblies having paired cavities within confining receptacles containing a hardenable plastic composition, the other assembly having paired forming balls which enter said cavities, b) having the patient execute full mandibular motion while said balls act upon said plastic composition to form paired three-dimensional impressions of said motion, and hardening said composition to form dimensionally stable solid recordings, c) transferring said recordings to one of the members of a dental articulator in a manner preserving the orientation of said recordings with the patient's teeth, and d) vertically engaging said recordings by paired stationary tracing balls having the same diameters as said forming balls, said tracing balls being positioned in a manner to preserve the alignment of the patient's maxillary and mandibular teeth.

2) Apparatus for forming a recording of the condylar motion of a dental patient and utilizing said recording for recon-structive purposes as part of a dental articulator, said apparatus comprising:
a) a maxillary recording assembly adapted to fit the patient's upper jaw and having: 1) a first rigid U-shaped bow having a straight forward bar and two extremities positioned at equal distances rearwardly of said forward bar, 2) box-like receptacles removably attached to said rearward extremities, and 3) an upper bite plate pendantly attached to said forward bar and displaced rearwardly therefrom, said upper bite plate having a lower abutment surface and an upper surface having a tooth receiving trough, b) a mandibular recording assembly adapted to fit the patient's lower jaw while aligned below said maxillary recording assembly and having: 1) a second rigid U-shaped bow having a straight forward bar and extremities provided with posts perpendicularly adjust-able with respect to said bow, 2) a smooth ball affixed to the uppermost extremity of each post and adapted to enter the receptacles of said maxillary recording assembly, and 3) a lower bite plate attached to said forward bar and extending rearwardly therefrom, said lower bite plate having an upper abutment surface and a lower surface having a tooth receiving trough, the relative positioning of said bite plates within said assemblies being such as to permit sliding contact between said abutment surfaces, c) an upper articulator member comprised of a rigid plate having a center zone, and equal left and right side arms radiating from said center zone in a straight line path and terminating in distal extremities having means for attachment of the receptacles of said maxillary recording assembly, and d) a lower articulator member comprised of: 1) a floor plate having rear and forward extremities, 2) a cross bar positioned above the plate and parallel thereto adjacent said rear extremity, and 3) means for adjust-ably positioning paired posts above said cross bar, said posts having smooth balls attached to their uppermost extremities, whereby e) the maxillary and mandibular recording assemblies interact to produce a solid recording confined within said receptacles, and said receptacles can be attached to said upper articulator member in a manner such that said upper articulator member is pivotably supported by interaction with the smooth balls associated with the cross bar of said lower articulator member,

3) The method of claim 1 wherein the paired cavities containing a hardenable plastic composition are associated with said maxillary recording assembly and are downwardly directed toward said forming balls associated with said mandibular recording assembly.

4) The method of claim 3 wherein said recordings are transferred within said receptacles to the upper member of said dental articulator,

5) The method of claim 4 wherein said transfer is accomplished by first bolting the maxillary recording assembly to a structural precursor of the upper member of the dental articulator, then removing all components of said maxillary recording assembly other than said receptacles, thereby transforming said precursor into the upper member of the-dental articulator.

6) The method of claim 5 wherein, prior to the bolting step, the patient's maxillary model is seated within the maxillary bite plate.

7) The method of claim 6 wherein, prior to removal of components of the maxillary recording assembly, the upper extremity of the patient's maxillary model is affixed to said structural precursor.

8) Apparatus of claim 2 wherein said upper articulator member is a structural precursor transformable into an upper articulator member by addition of the receptacles of said maxillary recording assembly.

9) Apparatus of claim 2 wherein means slideably associated with the cross bar of said lower articulator member pivotably engages the upper articulator member.

10) Apparatus of claim 2 wherein the rigid plate of said upper articulator member has a forward arm position centered between said left and right side arms, said forward arm holding a vertically adjustable post having a lower extremity which contacts said lower articulator member.