The document provides information about facebows, including: 1. It defines a facebow as a device used to record the relationship between the jaws and temporomandibular joints and orient dental casts on an articulator. 2. The main parts of a facebow are described as the U-shaped frame, condylar rods, bite fork, and locking device. 3. Facebows are classified as arbitrary or kinematic, with arbitrary facebows approximating but not precisely locating the hinge axis.

1. GOOD MORNING
SEMINAR

2. FACEBOW
Submitted by
Dr Asha Mary George
PG 2nd year
P.D.CH Patna

3. CONTENTS
• INTRODUCTION
• HISTORY
• DEFINITION
• PARTS
• CLASSIFICATION
• TYPES OF FACEBOWS
• CONCLUSION

9. Snow’s Facebow

11. DEFINITION OF FACEBOW
• Face-bow (Snow 1802) It is defined as, “A caliper like device
which is used to record the relationship of the maxillae
and/or the mandible to the temporomandibular joints”.
• “A caliper like device which is used to record the
relationship of the jaws to the temporomandibular joints and
to orient the casts on the articulator to the relationship of the
opening axis of the temporomandibular joint”- GPT

12. • The face-bow basically
contains three sections.
• One section represents the
plane of the cranium (U-
frame), the second section
represents the plane of the
maxilla (bite fork) and the
third section locks the first
two sections without altering
their plane (locking device)

13. Parts of a Face-bow
• The component parts of a face-bow are:
• U-shaped frame
• Condylar rods
• Bite fork
• Locking device
• Orbital pointer with clamp

14. U-shaped Frame
• It is a U-shaped metallic bar that forms the main frame of the
face-bow.
• All other components are attached to the frame with the help
of clamps.
• This assembly is large enough to extend from the region of
the TMJ to at least 2 to 3 inches anterior to the face and wide
enough to avoid contact with the sides of the face.
• This records the plane of the cranium

15. Condylar Rods
• These are two small metallic rods on either side of the free end of the
U-shaped frame that contacts the skin over the TMJ.
• help to locate the mandibular joint.
• transfer the hinge axis of the TMJ by attaching to the condylar shaft in
the articulator.
• Certain face-bows do not have a condylar rod.
• Instead they have an earpiece which fits into the external auditory
meatus. Facebows that have a condylar rod, to record the true hinge
axis (Centre of the condyle), are called Kinematic face-bows.
• Earpiece face-bows do not record the true hinge axis and hence they
are called Arbitrary face-bows hinge axis or the opening axis of the
TMJ

16. Bite Fork
• This is a U-shaped plate, which is
attached to the occlusal rims while
recording the orientation relation.
• It is attached to the frame with the help
of a rod called the stem.
• The bite fork should be inserted about 3
mm below the occlusal surface within the
occlusal rim. Sometimesthe bite fork is
attached to the occlusal surface of the
occlusal rim

17. Locking Device
• helps to attach the bite fork to the U-shaped frame.
• also supports the face-bow, occlusal rims and the casts during
articulation. It consists of a transfer rod . The ‘U’-shaped frame is attached
to the vertical transfer rod and can be locked with a thumb screw.
• The horizontal transverse rod connects the transfer rod with the stem of
the bite fork. After positioning the ‘U’-shaped frame and the bite fork, the
horizontal transverse rod should be positioned. It can be positioned
automatically by attaching it to the transfer rod and the bite fork and
tapping it. This type of assembly where the transverse rod gets
automatically positioned when tapped is called an auto-adjusting or self
centering assembly

19. Orbital Pointer
• It is designed to mark
the anterior reference
point (infraorbital
notch) and can be
locked in position with
a clamp. It is present
only in the arbitrary
face-bow

20. Types of Face-bows
• Face-bows can be classified as
follows:
1. Arbitrary face-bow
• • Facia type.
• • Earpiece type
• • Hanau face-bow (Spring bow)
• • Slidematic (Denar)
• • Twirl bow
• • Whipmix
2. Kinematic or hinge bow.

21. Arbitrary Face-bow
• It is the most commonly used face-bow in complete denture
construction. The hinge axis is approximately located.
• The condylar rods are positioned approximately 13 mm anterior
to the auditory meatus on a line running from the outer canthus
of the eye to the top of the tragus also called the cantho-tragal
line
• This is done using a Richey condylar marker. This is not done
for earpiece type face-bows where the earpiece is inserted into
the external auditory meatus

22. • This method generally locates the rods within 5 mm of
the true hinge axis of the jaws. As this is an arbitrary
hinge axis, errors in jaw relation may produce occlusal
discrepancies which should be corrected by minor
occlusal adjustments during insertion.

23. • Facia type :the hinge axis or the posterior reference point
is 13 mm anterior to the external auditory meatus and the
anterior reference point is the orbitale (midpoint of the
lower border of the orbit). The face-bow has a pointer
that can be positioned to the posterior reference point.
• Earpiece Type: The posterior reference point is the
external auditory meatus and the anterior reference point
is the orbitale. The earpieces engage into the posterior
reference points (the external auditory meatus).

24. SLIDEMATIC TYPE (DENAR)
• This facebow has an electronic device, which gives the reading that
can be seen in the anterior region.
• This reading denotes one-half of the patient’s inter-condylar
distance.
• These face-bows require specific articulators, which accept the
reading.
• The posterior reference point for this instrument is the external
auditory meatus and the anterior reference point is 43 mm superior
to the incisal edge of the upper central incisor for dentulous patients.

25. • In an edentulous patient the anterior reference point is 43
mm superior to the lower border of the upper lip in a relaxed
state.
• This anterior reference point is also used for Whipmix
articulators.
• The anterior reference point can be marked using a Denar
reference plane locator.
• The plane locator is an instrument which resembles a face-
bow.

29. DENAR REFERENCE PLANE
LOCATOR

32. TWIRL BOW
• It is an arbitrary type of face-bow that does not
require any physical attachment to the articulator.
• It is not commonly used for CD construction.
• It relates the maxillary arch to the Frankbort’s horizontal plane.
• A mounting guide is used to mount the transfer rod to the
articulator.
• It is easy to manipulate because the face-bow is not needed to
mount the maxillary cast in the articulator

33. WHIPMIX FACE-BOW
• These face-bows have a built-in hinge axis locator.
• It automatically locates the hinge axis when the
earpieces are placed in the external auditory meatus.
• It has a nasion relator assembly with a plastic nose piece.
• The nasion relator determines the anterior reference
point.

34. KINEMATIC FACE-BOW
• This face-bow is generally used for the fabrication
of fixed partial denture and full-mouth rehabilitation.
• It is generally not used for complete denture fabrication
because it requires a long and complex procedure to
record the orientation jaw relation

37. • The face-bow helps to orient the cast in the patient’s terminal hinge
axis.
• Hinge axis is the imaginary line around which the condyles can
rotate without translation.
• A terminal hinge position is the most retruded hinge position and it
is learnable, repeatable and recordable.
• It coincides with the centric relation.
• A 12-15° pure rotational
movement of the joint is possible in this position.
• The maximal incisal separation in this position is around 20 to 25
mm opening between the incisal edges

39. • The true hinge axis should be located and marked before using
the face-bow.
• The location of the hinge axis is then transferred to the
articulator with the face-bow.
• This face-bow requires a fully adjustable articulator to accept the
true hinge axis (THA).
• Since the patient’s hinge axis is transferred to the articulator, the
movement of the articulator will simulate the movements of the
joint made at the terminal hinge position.

40. WHIPMIX FACEBOW
• There are two different face-bows that can be
utilized with the Whip-Mix articulator.
• They are the Quick Mount or earpiece face-bow and the
adjustable axis or kinematic face-bow.
• The ear piece face-bow is most commonly used for complete
dentures.
• The earpiece face-bow may be obtained with either hex driver
adjustments or hand-tightening T screw adjustments.
• The adjustable axis face-bow is most commonly used with fixed
prosthodontic procedures or when the patient’s hinge or true
horizontal axis must be located.

41. The components of a Quick Mount facebow are (left to right) a bite
fork, the facebow with the nasion relator, and the Quick Lock Toggle
assembly

44. FACEBOW ARMAMENTARIUM
• Quick Mount facebow (with bite fork, nasion relator, and
Quick Lock Toggle assembly)
• Whip Mix articulator
• Plaster bowl
• Spatula
• Laboratory knife with no. 25 blade
• Trimmed maxillary cast
• Horseshoe wax wafers
• Mounting stone (Whip Mix)

45. • Two horseshoe wax wafers (Surgident Coprwax Bite Wafer, Heraeus
Kulzer) are heated in warm tap water until they become soft and flexible.
• A wafer is adapted to each side of the bite fork so that it is uniformly
covered
• The wax-covered bite fork is placed against the maxillary teeth.
• The attachment portion of the fork is centered on the patient’s midline.
bite fork is supported, and the patient is instructed to close lightly into the
wax to obtain shallow impressions of only the cusp tips
• The wax is cooled, and the bite fork is removed from the mouth.
• Excess wax is trimmed away.
• Any areas where soft tissue was registered on the wax must be completely
removed.

49. • The maxillary cast is set in the bite fork registration to confirm that the cast
seats firmly in the index with no rocking or instability.
• If the cast does not seat, first the occlusal surfaces of the cast are checked to make sure
there are no nodules of stone.
• If there are none, then either the registration or the cast is distorted and should be
remade.
• The bite fork is placed back in the mouth, and the patient is instructed to close to hold it
securely between the maxillary and mandibular arches.
• The patient is then asked to grasp both arms of the facebow and guide the plastic earpieces
into the external auditory meati, much as one would guide the earpieces of a stethoscope
• The shaft of the nasion relator is extended while the facebow is adjusted up or down to
center the plastic nosepiece on the patient’s nasion, and the thumbscrew is tightened
• Next, the thumbscrew is tightened on the top of the facebow
• The Quick Lock Toggle is slipped into the slot on the bite fork with the head of the
thumbscrew facing downward, and the screw is tightened
• The Quick Lock Toggle is stabilized, and the T screw is tightened

57. https://youtu.be/QvqkUVrhhhM
https://www.youtube.com/watch?v=QvqkUVrhhhM
https://youtu.be/ayYVWoIDMoI

58. DENAR FACEBOW
• The Denar Slidematic facebow (Whip Mix) is another self-
centering ear facebow that is easy to use .
• The technique for its use is described with the Denar Mark II
articulator (Whip Mix), an arcon semi-adjustable articulator.
This articulator also allows interchangeability of articulated
casts with other Mark II articulators without a loss of
accuracy.

59. FACEBOW ARMAMENTARIUM
• Denar Slidematic facebow (with bite fork, articulator
index, reference pin, and reference plane indicator)
• Felt-tip marker
• Denar Mark II articulator
• Plaster bowl
• Spatula
• Laboratory knife with no. 25 blade
• Trimmed maxillary cast
• Horseshoe wax wafers
• Mounting stone (Whip Mix)

60. FACEBOW RECORD TECHNIQUE
• The reference plane indicator is used to measure a point 43 mm above the
incisal edges of the maxillary incisors on the right side. This point is marked
with a felt-tip marker
• This will form the anterior, or third, reference point for the facebow transfer.
• Two horseshoe wax wafers (Surgident Coprwax Bite Wafer) are heated in warm tap
water until they become soft and flexible. A wafer is adapted to each side of the bite
fork so that it is uniformly covered.
• The wax-covered bite fork is placed between the teeth, with the bite fork shaft to the
patient’s right.
• The fork is centered by aligning the index ring on the fork with the patient’s midline.
• The patient is instructed to bite lightly into the wax to produce shallow indentations
of the cusp tips in the wax. The wax is cooled, and the bite fork is removed from the
mouth.
• Any excess wax is trimmed off the bite fork.

61. The maxillary cast is tried in the wax record to ensure that it will seat
without rocking. If the cast fails to seat, the occlusal surfaces of the cast are
checked for nodules of stone. If none are evident, there is a distortion in the
registration or the cast.
The reference pin is fastened to the underside of the face-bow by tightening
the thumbscrew (Fig 5-41). The clamp marked with a 2 should be on the
patient’s right (with the left side of the instrument viewed from the front)

62. HANAU WIDE VUE ARTICULATOR AND
FACEBOW

63. DIGITAL FACEBOW