this presentation describes the TMJ positions and the features of orientation jaw relation

1. ORIENTATION JAW RELATION

2. INTRODUCTION

5. Movements of TMJ involve:
Physiological movements = depression, elevation, protrusion,
retraction and laterally deviation.
Accessory movements = anteroposterior, transverse and
caudad/cephalad movements.

7. HINGLIKE MOVEMENT
used in opening and closing the mouth for the introduction of
food and, to a limited degree, for the crushing of certain
types of brittle food

8. PROTRUSIVE MOVEMENT
used in the grasping and incision of food

9. RIGHT OR LEFT LATERAL MOVEMENTS
use in the reduction
of fibrous as well as
other types of food

10. BENNETT MOVEMENT
 The bodily side shift of the mandible which, when it occurs, may be
recorded in the region of the rotating condyle on the working side.

12. Transvers axis Sagittal axis Vertical axis

13. ENVELOPE
OF
MOTION

14. ORIENTATION RELATIONS

15. ORIENTATION RELATIONS ARE THOSE THAT ORIENT THE
MANDIBLE TO THE CRANIUM IN SUCH A WAY, THAT,
WHEN MANDIBLE IS KEPT IN ITS MOST POSTERIOR
POSITION, THE MANDIBLE CAN ROTATE IN SAGITTAL
PLANE AROUND AN IMAGINARY TRANSVERSE AXIS
PASSING THROUGH OR NEAR THE CONDYLES. –
BOUCHER 10TH ED

17. An imaginary line around which the
mandible may rotate within the sagittal
plane. – GPT-8
Transverse hinge axis

18. Also called the Retruded contact position, it is that
guided occlusal relationship, occurring at the most
retruded position of the condyles in joint cavities.
GPT -8.
• Maximum range of terminal hinge rotation- about
Terminal Hinge position

19. FACE BOW

20. A caliper like instrument used to record
the spatial relationship of the maxillary
arch to some anatomic reference points,
and then transfer this relationship to an
articulator. (GPT-8

21. It orients the dental cast in same relationship to the
opening axis of articulator.
• Customarily the anatomic references are the mandibular
condyles transverse horizontal axis and one other selected
anterior point.
• Also called Hinge bow, Earbow, Kinematic facebow. (GPT-
8)

22. • In 1860 Bonwill concluded that the distance from the
center of the condyle to the median incisal point of the
lower teeth is 10 cm, but, he did not mention at what level
below the condylar mechanism the occlusal plane should be
situated.
• In 1866 Balkwill demonstrated an apparatus to measure
the angle formed by the occlusal plane of lower teeth &
the plane passing through the condyles & incisal plane of
lower teeth
History of the face bow

23. FRANKFORT HORIZONTAL
PLANE

25. HINGE AXIS

26. The hinge axis is an imaginary line
around which the condyles can rotate
without translation.

27. THEORIES OF
HINGE AXIS

28. (Aull, 1963) classified theories of hinge axis based upon four schools of
thought.
a. The absolute location of the hinge axis school
d. The split hinge axis school (Collinear – non collinear
controversy)
c. The non-believers of transverse axis location school
b. The arbitrary location of the hinge axis school

29. POSTERIOR REFERENCE
POINTS

30. BEYRON POINT
13mm anterior to the
posterior margin of the
tragus of the ear on a line
from the center of tragus
extending to the corner of
the eye.

31. BERGSTROM POINT
 10mm anterior to the center of
the spherical insert for the
external auditory meatus and
7mm below the Frankfort
horizontal plane. Bergstrom point
is found to be most frequently
closest to the hinge axis and
Beyron point is the next most
accurate posterior point of
reference.

32. GYSI POINT
 it is the most common point lies
13mm in front of the most upper
part of the external auditory
meatus on a line passing to the
outer canthus of the eye. This
method was proposed by Gysi,
Hanau, Snow and Gilmer and is
the point used today. .

33.  Other posterior points are which
are less frequently used and less
accurate.-13 mm in front of
anterior margin of meatus, 13
mm from foot of tragus to
canthus ,Ear axis.

34. ANTERIOR REFERENCE
POINTS

35.  Nasion minus 23mm- it lies on the
Deepest part of the midline
depression just below the level of
the eyebrows. The nasion guide, or
positioner, of the face bow fits
into this depression, designed to
be used with whip mix articulator.
This guide can be moved in and
out, but not up and down, from its
attachment

36.  Orbitale-In the skull, orbitale is
the lowest point of the infra
orbital rim. On a patient it can be
palpated through the overlying
tissue and the skin. One orbitale
and the two posterior points that
determine the horizontal axis of
rotation will define the axis
orbital plane.

37.  Orbitale minus 7mm-This plane
represents Frankfort Horizontal
plane

38.  Ala of the nose-The right or left
ala is marked on the patient and
the anterior reference pointer of
the face-bow is set.This method
uses the Campers Plane as the
plane of orientation

39.  43 mm superior from lower
border of upper lip- this plane
represents Denar reference
plane.Denar face bow uses this
reference point

40. TYPES OF FACEBOW

41. Kinematic Arbitrary
Facia type
Earpiece
type

42. Kinematic facebow
• The kinematic face bow allows for the
precise determination of the patient's
hinge axis (terminal hinge axis

43. Arbitrary Face Bow
Uses arbitrary or approximate points on the face as
the posterior points and condylar rods are
positioned on these points.
• They are a widely used type of face bow and are sufficient for
fabrication of most complete denture, fixed partial and
removable partial denture

44. Facia type face bow
This face bow takes its name from the
fact that it rests upon the face, like the
kinematic bow

45. Facia type face bow
This face bow takes its name from the fact that it
rests upon the face, like the kinematic bow

46. SPRING BOW
(HANAU’S FACE BOW)

48. Uses the Anterior Patient Reference of the Infra -
Orbitale Notch and the Posterior Patient Reference at
the Porion , the superior border of the External Auditor
Meatus .

49. Bitefork Preparation-DENTULOUS

50. EDENTULOUS

52. Bow Preparation

53. Patient Application

56. Measuring Bow
1. earplug
2. anterior reference
pointer
3. intercondylar distance
scale
4. “finger” lockscrew
Quick Lock Toggle
Assembly
1. dentulous bitefork
2 quick lock toggle
3 vertical shaft
4 articulator index

57. KINEMATIC FACEBOW

58. The device consists of the following parts:
1. Clutch/ bite fork
2 .Cross bar and stud
3. Axis indicator
4. Graph pad
5. Universal clamp/ screws

59. METHOD

61.  The recording is started with the patient seated in
upright position away from the back or head rest.
 The clutch is attached to the mandibular teeth or
the occlusion rim. It is stabilized to teeth using
impression compound.

62. The graph pad is positioned over the condyle.
The cross bar is attached to the clutch by
means of universal clamp.
The axis indicator is attached to the assembly
and positioned over the graph pad over the
condyle.

63.  The axis indicators are adjusted such that when
the patient opens and closes the mouth the
indicator no longer moves in an arc, rather it
rotates on a single point.
 The graph background is removed and that point
is marked on skin. The assembly is then removed

65. ADVANTAGES
1. Hinge axis location is exact
2. This leads to very much decreased chair side time required for
trimming
3. Occlusal discrepancies are well visualized, corrected and kept to
minimum especially in cases of full mouth rehabilitation, thus
increasing the prognosis and patient comfort

66. DISADVANTAGES
1.Patient comfort is compromised while recording because of the
armamentarium used
2. The insertion of clutches might lead to altered position of
condyle which might interfere with the absolute location
3. It is technique sensitive .
4. It can be used only with a fully adjustable articulator
5. The procedure is time consuming.

67. PANTOGRAPH

68. in dentistry, an instrument used to graphically
record, in one or more planes, the paths of
mandibular movement and to provide information
for the programming of an articulator
an instrument used for copying a planar figure to any
desired scale

69. PANTOGRAPHIC TRACING
a graphic record of mandibular movement usually
recorded in the horizontal and sagittal planes as
registered by styli on the recording tables of a
pantograph or by means of electronic sensors

70. MECHANICAL PANTOGRAPH
considered accurate and reliable however the
technique is time consuming and technique
sensitive.
(McCollum 1955, Clayton et al 1971, Beard et al 1986 and
Pelletier 1991)

73. MECHANICO ELECTRONIC
permit easier and quicker recording of
mandibular movements, programming the
articulator and storing permanent records
compared with traditional pantograph.

75. Cadiax maxillary and mandibular face-bows

76. Mechano electronic recorders are so named
because styli physically move across digital
recording plates, mandibular movement thus
recorded by the digital contact plates and processed
by the software, values for programming most
articulators are then generated by the computer.

77. OPTO-ELECTRONIC RECORDERS
Have coded wireless sensors attached to maxillary and
mandibular face bows, the sensor movement is
optically tracked by camera , three dimensional
information is processed by the computer and
articulator values are generated

78. Cadiax Compact 2 (

79. Computerized Pantograph Mounted on Fully Adjustable

80. THANK YOU!!