US3530293A - Cephalometer device - Google Patents

Description

Se t. 22, 1970 B. F. WEHMER 3,530,293

CEPHALOMETER DEVICE Filed April 1, 1968 2 Sheets-Sheet 1 IL" A48 @613 0 20 6 Ira/enforfirm n0j7h/e/zme7;

g fl 446% M Sept. 22, 1970 B. F. WEHMER CEPHALOMETER DEVICE 2 Sheets-Sheet 2 Filed April l, 195s g ll l IQWM m Q mm wk 5 W 0 United States US. Cl. 25050 7 Claims ABSTRACT OF THE DISCLOSURE A cephalometer including a base support member having counterbalanced support arms, a head positioning fixture disposed on one of the support arms and defining a generally fixed alignment axis, an X-ray head adjustably supported on another of the support arms and including an X-ray beam-directing tube, and a fixator having a support plate pivotally connected to one of the support arms. The fixator includes a fixator channel adapted to selectively receive and maintain the beam-directing tube in axial alignment with the alignment axis of the head positioning fixture when the fixator is disposed in a first posi tion, the fixator being movable to a second position allowing operation of the X-ray head independently of the fixator. A seat and headrest are associated with the base support for conveniently locating a subject generally adjacent the X-ray head.

BACKGROUND OF THE INVENTION The present invention relates to cephalometer devices, and more particularly to a cephalometer having an adjustable X-ray head and fixator means adapted to maintain the X-ray head in a fixed alignment position while being movable to allow use of the X-ray head independently of the fixator.

In the practice of orthodontics, it is generally required to take radiographs for cephalometric studies. Conventional cephalometers employ a head positioning fixture to receive the subjects head in a selected position there in, and include an X-ray head disposed in fixed relation such that its X-ray beam is maintained in proper align ment with an alignment axis defined by the head positioning fixture.

Frequently, in conjunction with cephalometric studies, the doctor also desires radiographs of a specific area of the subjects jaw for performing intraoral work. In the usual case, the doctor has to resort to a separate dental X-ray machine removed from the cephalometer, thereby requiring movement of the subject to a separate area. This substantially increases the time required in obtaining the necessary radiographs, and further necessitates the expense of a separate dental X-ray machine, both of which factors contribute to the cost borne by the patient.

SUMMARY OF THE INVENTION It is one of the primary objects of the present invention to provide a cephalometer device having an adjustable X-ray head which may be conveniently used for intraoral radiograph studies, and which cephalometer includes fixator means adapted to maintain the X-ray head in generally fixed alignment with an alignment axis defined by a head positioning fixture for cephalometric studies.

atent 3,530,293 Patented Sept. 22, 1970 Another object of the present invention is to provide a counterbalanced cephalometer device including support arm means which support a head positioning fixture for cephalometric studies, an adjustable X-ray head, and fixator means adapted to selectively maintain the X-ray head in generally fixed alignment with an alignment axis defined by the head receiving fixture, the fixator means being movable to a second position to allow use of the X-ray head independently of the fixator means.

A feature of the present invention is the use of a fixator comprising a pivotally connected support plate having a fixator channel disposed thereon, which arm is movable between a first position wherein the fixator channel can receive and maintain the X-ray head in a predetermined fixed position and a second position wherein the fixator channel is remotely disposed from the X-ray head.

A further feature of the present invention is the provision of a fixator channel as above-described having a lead and felt lined chamber and a door member operable to allow ready insertion of an X-ray beam-directing tube into the fixator channel for maintaining the beam-directing tube in generally fixed position.

A preferred embodiment of a cephalometer according to the present invention includes a generally upstanding support base having a vertically movable carriage thereon, which carriage has counterbalanced support arms thereon for movement therewith. A head positioning fixture is disposed outwardly of one of the support arms to receive a subjects head in generally fixed relation therewith and defines an alignment axis position for taking cephalometric radiographs. An X-ray head is adjustably supported on another of the support arms so as to be adjustable relative to the head positioning fixture. A fixator comprising a pivotally mounted support plate having a fixator channel thereon is movable between first and second positions. The fixator channel is adapted to receive an X-ray beam-directing tube of the X-ray head when the fixator is in its first position such that the X-ray beam is aligned with the aforementioned alignment axis of the head receiving fixture. The fixator is selectively movable to a position removed from the X-ray head to allow use and operation of the X-ray head for intraoral dental work independent of the fixator. Preferably, a seat and headrest are adjustably disposed on the support base to provide convenient positioning of the subject relative to the X-ray head for the taking of intraoral radiographs. My cephalometer thus provides a means for fixing the X-ray beam-directing tube of the X-ray head in proper alignment with the alignment axis defined by the head receiving fixture, while allowing the X-ray head to be readily positioned for intraoral dental radiographs.

Further objects and advantages of my invention, together with the organization and manner of operation thereof, may best be understood by reference to the following description of preferred embodiments of the invention when taken in conjunction with the accompanying drawings, in which like reference numerals designate like parts throughout the several views.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of a cephalometer constructed in accordance with a preferred embodiment of 03 the present invention, showing the X-ray head fixator in an inoperative position;

FIG. 2 is a perspective view showing the X-ray head and fixator of FIG. 1 disposed in operative cooperating relation;

FIG. 3 is a foreshortened view, in elevation, looking in the direction of arrows 3-3 of FIG. 2 and showing the fixator support arm and X-ray beam tube receiving channel disposed in upward pivoted position;

FIG. 4 is a partial top view of the fixator channel and support plate, with the door member thereof being shown in open position in dotted lines;

FIG. 5 is a top view of the adjustable X-ray head support assembly, with the X-ray head support yoke broken away; and

FIG. 6 is a side elevational view of the X-ray head support assembly of FIG. 5.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings, and in particular to FIG. 1, there is illustrated a cephalometer, indicated generally at reference numeral 10, constructed in accordance with a preferred embodiment of the present invention. The cephalometer 10 generally comprises an upstanding support base, shown generally at 12, which supports counterbalanced support arm means including three support arms 14, 16 and 18 through a carriage 20 selectively movable on the support base; a head receiving and positioning cephalometric fixture, indicated generally at 22; an X-ray head, indicated generally at 24; fixator means, indicated generally at 26, for selectively positioning the X-ray head; and a seat, indicated generally at 28, upon which a subject may be seated during the taking of intraoral dental radiographs.

The upstanding support base 12 includes a cylindrical lower portion having a floor engaging plate 32 suitably secured to the lower end thereof. A generally rectangular elongated support plate 34 is suitably secured to the upper end of the lower portion 30 of the support base and is preferably provided with suitable means (not shown) to secure the upper end thereof to a wall such that the support base is disposed in generally vertical upstanding relation.

The support plate 34 of the upstanding support base 12 receives the carriage 20 in supporting relation thereon in a conventional manner, the carriage being slidable along the longitudinal length of the support plate 34 guided by channels 36. A locking knob 38 is suitably threadedly supported by the carriage 20 and adapted to engage the outer side edge of the corresponding guide channel 36 in locking relation when threaded inwardly into the receiving aperture of the carriage in a known manner. The support arms 14 and 16 are fixedly secured in generally horizontal relation to the carriage 20 so as' to be vertically movable therewith, while the support arm 18 is pivotally connected to the carriage 20 and support arm 16 for vertical movement therewith as will be more fully described hereinbelow.

The support arm 14 extends outwardly from the carriage 20 and supports the head positioning cephalometer fixture 22. The head positioning fixture 22 is of known design and includes downwardly extending head positioning elements 40 and 42 which are selectively positionable relative to a head plate 44 to provide a means for receiving a subjects head in generally fixed relation to the fixture 22. The head positioning elements 40 cooperate with the head plate 44 to define an alignment axis for the taking of cephalometric radiographs when a subjects head is properly positioned within the head positioning fixture 22. The head positioning fixture 22 includes a radiograph plate support bracket 46 supported through a suitable adjustable bracket 48 for proper positioning relative to the head positioning elements 40 and 42.

Preferably, a generally vertically disposed lock rail 50 is fixedly secured to a wall surface (not shown) and slidably received through an appropriate aperture in the support arm 14 adjacent the outer end thereof. The lock rail 50 provides a means for locking the support arm 14 and carriage 20 in a selected vertical position on the base support 12, as through a threaded lock screw 52, when Working adjacent the fixture 22.

The support arm 18 is pivotally connected to the carriage 20 through a pivot pin 56 and a hinge bracket 54 fixed to the carriage. The pivot pin 56 is received through an appropriate aperture in the hinge bracket 54 and extends downwardly through arm 18, a hollow downwardly depending spacer shaft 60 suitably secured in normal relation to the lower surface of support arm 18, and the lower support arm 16. The pivot pin 56 may be retained in proper axial relation by conventional means such as end cap nuts, snap rings or the like. The spacer shaft 60 is of a length sutficient to maintain the support arm 18 in spaced parallel relation to support arm 16 for pivotal movement in a generally horizontal plane about the pivot axis of pivot pin 56. If desirable, a conventional spring loaded detent pin means 58 may be supported by a lug 61 fixed to the spacer shaft 60 adjacent the upper surface of the support arm 16. The detent pin means 58 is adapted to cooperate with an appropriate recess or opening (not shown) in the upper surface of support arm 16 such that the pin is releasably received in the recess when the support arms 16 and 18 lie in a common vertical plane.

Referring now to FIG. 1, taken in conjunction with FIGS. 5 and 6, the support arm 18 is adapted to support a spring balanced X-ray head support arm assembly, indicated generally at 62. The support arm assembly 62 is of generally known construction and includes an elbow 64 pivotally connected to the outer end of the support arm 18 through a pivot pin 66 secured to the support arm 18 in generally transverse relation to the longitudinal axis thereof. With the elbow 64 pivotally connectedto the support arm 18 through pivot pin 66, it can be seen that the elbow 64 may be rotated in a generally horizontal plane about the pivotal axis 66. The elbow 64 is provided with a suitable cavity therein to receive the end portions of a link member 68 and a spring housing 70. The link member 68 is pivotally connected to the elbow 64 through a pivot pin 72 suitably fixedly secured to the elbow in transverse relation to the pivotal axis 66. The end of the link member 68 opposite pivot pin 72 is pivotally connected to and between upstanding leg portions 76 of a housing member 78 through a pivot pin 80.

The spring housing comprises an elongated shell having a generally rectangular cross section and is pivotally connected to the elbow 64 through a pivot pin 74 disposed in parallel relation to the pivot pin 72. The end of the spring housing 70 opposite the pivotal connection 74 is received within a suitable recess or cavity within the housing member 78 and has a shaft 82 fixedly secured thereto such that the shaft is disposed in parallel relation to the pivot pin 80. The shaft 82 extends outwardly from opposite sides of the spring housing 70', with each end portion being slidably received in a suitable through-bore 84 in the housing member 78. Link member 68, spring housing 70, elbow 64 and housing member 78 cooperate to form a parallelogram arrangement through the pivotal connections 72, 74, and 82. With the elbow 64 disposed in generally fixed vertical relation on the support arm 18, the housing member 78 may be selectively moved upwardly or downwardly relative to the elbow with the plane containing the pivotal axes 80 and 82 being maintained in vertical relation throughout such upward and downward movement, as considered in FIG. 6.

The X-ray head support assembly 62 includes a control lever 86 suitably secured to an annular collar 88 which is fixedly disposed on one end of the shaft 82 through a key 90. A knob 92 is threadedly received on the outer end of the shaft 82 adjacent the collar '88 and serves to adjust the friction between the side surface of the collar adjacent the housing member 78 when tightened onto shaft 82 in a known manner. The lever 86 provides a means for raising and lowering the housing 78 relative to the elbow 64 through the parallel link arrangement defined by link member 68 and spring housing 70. Inward tightening of the knob 92 may be effected to vary the frictional relation between the collar 88 and the housing 78 and thereby selectively Vary the ease with which the housing 78 may be moved upwardly or downwardly.

The X-ray head support assembly 62 further includes a pair of coil springs 94 supported by and disposed between a pair of parallel pins 96 and 98. The springs 94 are maintained in tension and serve as counterbalance means to urge the housing member 78 to a position wherein the link member 68 and spring housing 70 are disposed in generally horizontal positions as illustrated in FIG. 6. The pin 96 is suitably aflixed to an end portion 100 of link member 68, While the pin 98 is primarily supported by a spring clevis 102. The spring clevis 102 is pivotally supported upon the shaft 82 secured to the spring housing 70 and is maintained in generally fixed position relative to the housing member 78 through a spring tension adjusting screw 104 which is threadedly received within a connecting link 106 pivotally connected to the pin 98. It can be seen that inward movement of the adjusting screw 104 into the connecting link 106 will effect pivotal movement of the spring clevis 104 in a clockwise direction, when considered in FIG. 6, and thereby increase the tension on the springs 94. Such adjustment is effective to adjust the counterbalance established by the springs 94 which tends to oppose movement of the housing 78 in an upward or downward direction relative to the elbow 64.

An X-ray head supporting yoke 108 is suitably supported by the housing member 78 for rotational movement about a generally vertical axis and serves to support the X-ray head 24 through a horizontal pivotal axis 110 in a conventional manner. With the X-ray head 24 so supported, it may be readily rotated about the horizontal pivotal axis 110 and also about the vertical axis defined by the connection of yoke 108 to the housing member 78. The X-ray head 24 may also be rotated in a generally horizontal plane about the pivot axis 66 through the X-ray head support assembly 62. In addition, the X-ray head 24 may be moved upwardly or downwardly relative to the support arm 18 through upward or downward movement of the housing member 78, the X-ray head support assembly 62 being maintained in the selected position through frictional adjustment of knob 92 as above described.

The X-ray head 24 includes a conventional X-ray beamdirecting tube 112 which serves to control the direction of X-ray beam emission in a known manner. The X-ray beam-directing tube 112 may have a generally cylindrical peripheral configuration as shown in FIG. 1, or any other conventional configuration such as a cone.

In making cephalometric radiographs of a subjects head when positioned within the head receiving cephalometer fixture 22, it is necessary that the X-ray beamdirecting tube 112 of the X-ray head 24 be generally fixedly positioned such that the emitted X-ray beam is aligned with the aforedescribed alignment axis of the head receiving fixture 22. To effect such alignment for taking cephalometric radiographs, the present invention provides a fixator means 26 adapted to cooperate with the X-ray beam-directing tube 112 of the adjustable X-ray head 24.

The fixator means 26 includes a support plate or arm 118 which is pivotally supported by the support arm 16 adjacent the lower edge thereof through a conventional hinge member 120. Referring to FIG. 3, taken in con junction with FIGS. 1 and 2, a stop member 122 is suitably secured to a forward surface 124 of the support arm 16 and has a pair of downwardly extending spaced lock pins 126 secured thereto through screws 128. The lock pins 126 extend downwardly below the plane of the lower surface of support arm 16 and are received within corresponding apertures 130 in the support plate 118 when the support plate is disposed in a first generally horizontal position as shown in FIG. 3. Each of the lock pins 126 has a recess 132 therein to receive an associated portion of a cam lock shaft 134 when the support plate 118 is disposed in the horizontal position. The cam lock shaft 134 extends transversely of the support plate 118 and is rotatably retained within appropriate apertures in longitudinally extending depending fins 136 which are suitably secured in normal relation to the bottom surface of the support plate. The cam lock shaft 134 has a recessed groove 138 therein adjacent each of the lock pins 126, which grooves allow entry of the cam lock shaft into the recesses 132 of the lock pins during movement of the support plate to the horizontal position. Upon entry of the locking shaft into the recesses 132, the cam lock shaft is rotated to lock the support plate 118 in the horizontal position shown in FIG. 3. A suitable lever member 140 is secured to an outer end of the cam lock shaft 134 for effecting rotational movement thereof during locking and unlocking of the cam lock shaft within the depending lock pins 126.

With the support plate 118 of the fixator means 26 pivotally connected to the support arm 16 as above described it can be seen that the support plate may be $6- lectively moved between a first horizontal position wherein it may be fixedly locked through engagement of the cam lock shaft 134 with the depending lock pins 126 as shown in FIG. 2, and a second position wherein it depends downwardly as shown in FIG. 1.

The fixator means 26 includes a fixator channel, indicated generally at 142, supported adjacent the outer end of the support plate 118 opposite the hinged connection 120. The fixator channel 142 comprises a generally rectangularly shaped hollow housing shell 144 having a square cross section of a size suflicient to receive the cylindrical X-ray beam-directing tube 112 as will become more apparent hereinbelow. The housing shell 144 may be made from suitable sheet metal and is secured to an up standing leg portion 146 of the support plate 118 such that the longitudinal axis of the housing 144 is disposed in generally transverse relation to the longitudinal axis of the support plate.

Referring to FIGS. 3 and 4, the end of the housing shell 144 farthest from the support base 12 is open-ended and the end thereof closest to the support base is provided with a cap member 148. The cap 148 is made of a material which will not adversely affect the X-ray beam emitted from the X-ray beam-directing tube 112 when disposed within the fixator channel 142 during operation, as will be more fully described hereinbelow. The side of housing shell 144 opposite the upstanding leg portion 146 of the support plate 118 is provided with a closure door 150 pivotally connected to the housing 144 at 152. The door 150 has a door lock or latch 154 thereon adapted to selectively lock the door in closed position with the housing 144.

The door latch 154 comprises a generally elongated spring plate connected as by a rivet at 156 to an upper horizontal edge portion of the door 150. The elongated spring plate of the door latch 154 has a thumb knob 158 suitably aflixed to the end thereof adjacent the open end of housing 144, which thumb knob has a downwardly extending retainer pin 160 formed thereon. The retainer pin 160 is received through an appropriate aperture in the upper horizontal edge portion of the door 150 and a corresponding aperture in the upper surface of housing shell 144 such that upon closing the door 150, the retainer pin serves to retain the door in closed position in a conventional manner.

A lead shield lining 162 is suitably secured to the inner peripheral surface of the housing shell 144 to prevent stray radiation from the fixator channel. Similar lead shield linings 163 and 165 are provided on the inner surfaces of the door 150 and the end cap 148, respectively. The lead shield lining 165 on the inner surface of the end cap 148 has a central aperture 164 therein of a diameter equal to the diameter of the X-ray beam emitter aperture in the outer end of the X-ray beam directing tube 112 to collimate the X-ray beam when used in conjunction with the fixator means 26.

Preferably, a felt lining 166 is suitably secured to the inner surfaces of the lead shield linings 162 and 163 to provide a resilient surface for firmly receiving the X-ray beam-directing tube 112.

The relationship between the support arm 14, the support arm 16, the relative position of the aforedescribed alignment axis defined by the head receiving fixture 22, and the longitudinal axis of the fixator channel 142 on the support plate 118 of the fixator means 26 is such that when the fixator means is locked in the upper horizontal first position, the longitudinal axis of the fixator channel is aligned with the alignment axis of the head receiving fixture 22. When the cam lock shaft 134 is rotated to release the support plate 118 from the depending lock pins 126, the fixator channel 142 and the support plate may be pivoted downwardly to a position wherein the fixator channel is removed from the general vicinity of the X-ray head 24.

The seat 28 is adjustably supported through a conventional notched shaft 170 received through a generally horizontally disposed support member 172. The shaft 170 and seat 28 can be selectively positioned relative to the support member 172 through a hand screw lock 174. The horizontal support member 172 is suitably aifixed to a cylindrical tubular sleeve 176 disposed on the cylindrical shaft 130 of the base support 12 for vertical sliding movement thereon. Any conventional means such as a pin 178 may be employed to maintain the sleeve 176 in a preselected vertical position on the cylindrical shaft 30, it being understood that a plurality of vertically spaced holes are conventionally provided in the shaft 30 to selectively receive the pin 178. The seat 28 may thus be adjusted both through vertical movement of the sleeve 176 on the shaft 30 and through vertical adjustment of the notched shaft 170 in support member 172. The seat 28 may be rotated about the shaft 30 of base support 12 such that it may be moved to an out-of-the-way position when not in use.

A headrest comprising a pair of spaced vertically disposed head pads 180 is suitably supported through a bracket 182 on the upper surface of the support arm 16 and is adapted for selective horizontal movement along the support arms. The bracket 182 is maintained in selected position by a securing nut 184.

As noted above, the support arms 14, 16 and 18 are counterbalanced about the carriage 20 to allow the operator to raise and lower the support arms with little effort. The support arms 16 and 18, along with the supported X-ray head 24 and fixator means 26, serve to counterbalance the support arm 14 along with the supported cephalometric fixture 22, thereby allowing the operator to readily move the carriage 20 and associated support arms upwardly or downwardly on the support plate 34 during operation of the cephalometer device 10.

Having thus described the elements comprising a preferred embodiment of a cephalometer in accordance with the present invention, its operation will now be briefly described. As noted above, in making cephalometric radiographs it is important that the axis of the X-ray beam be aligned with the alignment axis defined by the head positioning fixture 22. To effect such alignment, the fixator channel 142 of the fixator means 26 is raised to a generally horizontal position through upward pivotal movement of the support plate 118 and is locked in such position through the cam lock shaft 134. The door 150 of the fixator channel 142 is then opened to allow introduction of the X-ray beam directing tube 112 of the X-ray head 8 24 into the fixator channel as shown in FIG. 2. With the X-ray beam-directing tube 112 so disposed within the fixator channel 142, proper alignment for the taking of cephalometric radiographs is assured.

When the doctor or operator desires to make intraoral dental radiographs requiring positioning of the X-ray head 24 in a position other than that shown in FIG. 2, the door 150 of the fixator channel is opened and the X-ray beamdirecting tube 112 removed therefrom. The cam lock shaft 134 is then rotated to an unlocking position through the lever 140 and the support plate 118 and fixator channel 142 of the fixator means 26 pivoted downwardly to a second position wherein the fixator channel is removed from the area of the X-ray head 24. The operator may then place the subject on the seat 28 with the subjects head positioned against the head pads 180. The X-ray head 24 may thereafter be moved to the desired position through horizontal pivotal movement of the support arm 18, pivotal movement of the X-ray head support assembly 62 about its pivotal axis 66, upward and downward movement of the housing 78 through the parallelogram arrangement of links 68 and 70, and rotation of the X-ray head about the horizontal pivotal axis and the vertical axis defined by the connection of the yoke 108 to the housing 78.

The cephalometer device 10 described hereinabove meets the requirements for a fixed alignment X-ray head when making cephalometric radiographs, while allowing great flexibility of the X-ray head for use in intraoral dental X-ray work.

While I have described my invention as being particularly suitable for use in cephalometric studies, my inven tion will also find ready application in other instruments where the alignment of a generally movable instrument with a second fixed position instrument is desired.

While a preferred embodiment of my invention has been shown and described, it will be obvious to those skilled in the art that changes and modifications may be made therein without departing from the invention in its broader aspects, and therefore, the appended claims are intended to cover all such. changes and modifications as fall within the true spirit and scope of my invention.

What is claimed is:

1. A cephalometer comprising base support means, support arm means associated with said base support means, a head positioning fixture supported by said support arm means and defining a generally fixed alignment axis position, an X-ray head adjustably supported by said support arm means and including an X-ray beam-directing tube, and fixator means including a support plate pivotally connected to said support arm means for selective movement between first and second positions, said fixator means including a fixator channel comprising a housing shell disposed on said support plate and adapted to selectively receive said beam-directing tube in fixed relation therewith, said housing shell being disposed to receive and maintain said beam-directing tube in axial alignment with the alignment axis defined by said head positioning fixture when said support plate is in said first position, and being movable to said second position removed from said X-ray head whereby said X-ray head may be selectively positioned independently of said housing shell.

2. A cephalometer as defined in claim 1 wherein said housing shell includes a door member operable to allow entry of said X-ray beam-directing tube into said fixator channel and retain said beam-directing tube within said channel in aligned relation with the alignment axis of the head positioning fixture.

3. A cephalometer as defined in claim 1 including a lead shield lining disposed on the inner surface of said housing shell, said lining having an aperture therein to collimate the X-ray beam of said beam-directing tube.

4. A cephalometer as defined in claim 3 including a felt lining disposed on said leading lining to snugly receive said X-ray beam-directing tube.

9 10 5. A cephalometer as defined in claim 1 including lock References Cited means operatively associatedwith said support plate to UNITED STATES PATENTS selectlvely lock said plate in said first position. 6. A cephalometer as defined in claim 1 including seat 2264,4110 12/1941 Schler 250 50 means associated with said base support means, and means 28461587 8/1958 Q Q 250-50 supporting said seat means generally adjacent said X-ray 5 2903588 9/1959 Mmmch head removed from said head positioning fixture.

7. A cephalometer as defined in claim 1 including ad WILLIAM LINDQUIST Pnmaly Exammer ditional headrest means supported by said support arm C. E. CHURCH, Assistant Examiner means and adapted to define a position to receive the subjects head when using the X-ray head independent of said 10 S- 'C X-R- fixator means. 25065

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