This document provides an overview of horizontal jaw relation and methods for recording centric relation. It defines centric relation as the maxillomandibular relationship where the condyles are positioned in the anterior-superior position against the articular eminences without tooth contact. Several methods for recording centric relation are described, including the pressureless method, pressure method, needle-house method, Patterson method, and graphic methods using arrow point tracing or pantographic tracing. Recording centric relation accurately is important for the functional efficiency and longevity of complete dentures.

1. GOOD
AFTERNOON
Presented by:- Rutvik A. Patel (IV BDS)
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2. HORIZONTAL JAW
RELATION
 CONTENTS:
• Introduction
• Types
• Centric relation
• Significance
• Salient feature
• Retruding the mandible
• Factors influencing centric relation
• Method of recording centric relation
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3.  INRODUCTION
 Jaw relation is defined as any relation of the
mandible to maxilla
 It is recorded to measure the
extensibility & movements permissible
by the patients TMJ
TYPES
Orientation
Vertical
Horizontal
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4. HORIZONTAL RELATION
“Maxillomandibular relation in which the condyles
articulate with the thinnest avascular portion of
their respective discs with the complex in the
antero-superior direction against the slope of
articular eminence.”
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5. • Horizontal jaw relation
• Relationship of mandible to maxilla in a
horizontal plane
• Two types:
1. Centric jaw relation
2. Eccentric jaw
relation
Horizontal jaw
relation
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6. CENTRIC JAW RELATION
What is
centric
relation ?
“ A maxillomandibular relationship in which the
condyles articulate with the thinnest avascular
portion of their respective disks with the
complex in the anterior superior position against
the slopes of the articular eminences. This
position is independent of tooth contact. This
position is clinically discernible when the
mandible is directed superiorly and anteriorly
and restricted to a purely rotary movement
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about a transverse horizontal axis.”

7. SIGNIFICANC
E
• Proprioceptive impulses guide the
mandibular movement
• The centric relation position acts as a
proprioceptive centre to guide the
mandibular movements.
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8.  SALIENT FEATURES OF CENTRIC
RELATION
1. Learnable, Repeatable, Recordable.
2. Act as a centre
3. Functional movements are
performed in this position
4. Most unstrained position
5. Arrangement of muscle acting on
TMJ
6. The cast should be mounted in
centric relation
“It is a learned position and the dentist should
teach the patient”
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9. RETRUDING THE MANDIBLE
A. Verbal instruction to the patient
B. Get the feeling of pushing your upper jaw out and close
back teeth together
C. Retrusion of the tongue
D. Rapid tapping of the occlusal rim
E. Tilting head backwards
F. Ask patient to swallow
C
D
E
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10. • Difficulties in retruding mandible
1. BIOLOGICAL CAUSE
• Lack of muscle co-ordination
• Habitual eccentric jaw relation
2. PSYCHOLOGIC PROBLEM
• Lack of proper instruction by dentist
• Inability to follow dentist
3. MECHANICAL PROBLEM
• Poorly fitting base plates
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11. FACTORS INFLUENCING CENTRIC RELATION
1. The resiliency of the supporting tissues
2. The stability of the recording bases
3. The TMJ and its neuromuscular mechanisms
4. The character of the pressure applied
5. The technique & devices used
6. The skill of the dentist
7. The health and cooperation of the patient
8. The maxillomandibular relationship
9. The posture of the patient
10. The character or size of the residual alveolar arch
11. The amount and character of the saliva
12. The size and position of the tongue
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12. METHOD OF RECORDING CENTRIC RELATION
Physiologic method
• Pressureless or static method
• Pressure method
Functional method
• Needle-House method
• Patterson method
Graphic method
• Intraoral method
• Extraoral method
Radiographic method
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13. Physiologic method
Troug
h
A
 Pressureless or static method
1. Nick & Notch method
• most commonly used method
 PROCEDURE
A.
B
Notch
B.
C.
D.
E.
C
Remove 3 mm of wax either side on
mandibular occlusal rim till the distal end.
“This depression is called as trough”.
Nick & Notch made on the corresponding
area on maxillary occlusal rim.
Aluwax is placed in trough & soften it and
place in patients mouth.
Ask patient to bite on occlusal rims
Remove it and cut the excess
D
4.5
mm
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14. 2. Stapler pin method
• After recording centric relation occlusal
rims are indexed using a bunch of
stapler pins.
• This method is not preferred because
centric relation record cannot be verified
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15. Pressure method
• In this method we will fabricate lower
occlusal rim excess in height
• Entire lower occlusal rim is softened &
inserted in mouth
• Guide patient to close mouth in centric
relation till the predetermined vertical
dimension
• Remove occlusal rims, cool it and articulate
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16. Functional
 Needle-House method
method
- uses occlusal rims made from
impression compound with four
metal styli placed in the maxillary
rim.
MP
MRL
- when the mandible moves with the
styli contacting the rim, the styli cut
four diamond shaped tracings.
ML
L
CR
- the tracings incorporate the
movements in three planes, and the
records are placed on a suitable
articulator to duplicate the record.
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MP-Maximum protrusive, MLLMaximum left lateral, MRLMaximum right lateral, CRCentric relation

17.  Patterson Method
- Uses wax occlusal rims.
- A trench is made in the mandibular
rim, and a mixture of half plaster and
half carborudum paste is placed in
the trench.
- When the plaster and carborundum
are reduced to the pre-determined
vertical dimension, patients are
instructed to retrude the mandible
and occlusion rims joined.
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18. Graphic
method
• Use graphs or tracings to record the centric jaw relation
• Most accurate method
Types:
1. Arrow point tracing
- Single plane
2. Pantograph
- Three dimensional
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19.  Arrow point tracing
• Tracing made using Gothic arch tracer

•
•
•
Concept
Pen like pointer
Recording plate
Central bearing
device
Central bearing
plate
Central bearing point
 Central arrow point tracing
• “The pattern obtained on the
horizontal plate used with central
bearing tracing device”
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20. Types of Arrow point tracer
1. Intraoral
• Central bearing device is located
intra orally
 Procedure
• Insert central bearing device into
mouth
• Adjust central bearing point on
central bearing plate
• Now patient is asked to do
movement, then tracing is removed
and examined
• It should resemble arrow point with
sharp apex
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21. 2. Extraoral
• Have attachment that projects outside
the mouth
Occlusal rim
 Procedure
• Central bearing device is attached with
the occlusal rims
• Place occlusal rims in the mouth and
patient is asked to do movements
• Tracing is examined for sharp apex
Occlusal
rim
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22. Pantographic tracing
• Most accurate method available
• Pantographic tracer: An instrument used
to graphically record one or more planes
path of mandibular movement and to
provide information for the programming
of the articulator.
• It has 6 flags:
- 4 near condyle
- 2 in anterior region
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23. CONCLUSIO
N
Fabrication of complete denture involves
various steps out of which recording jaw
relation is one of the most important step.
There are various technique used to record
jaw relation.
By recording proper jaw relation functional
efficiency & longevity of the prosthesis is
increased.
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24. REFEREN
CE
• Textbook of PROSTHODONTICS
Deepak Nallaswamy {First edition-2009
(Deepak Nallaswamy
Veeraiyan, Karthikeyan
Ramalingam, Vinaya Bhat )}
• Prosthodontic Treatment for Edentulous
Patient Boucher{12th Edition George A.
Zarb, Charles L. Bolender, Steven E.
Eckert, Rhonda F. Jacob, Aaron H.
Fenton, Regina Mericske-Stern)}
• Google search
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