This document discusses horizontal jaw relation and methods for recording centric relation. There are two types of horizontal jaw relation: centric and eccentric. Centric relation is the maximum intercuspal position with equal condylar joint space bilaterally. Methods for recording centric relation include physiological (tactile check bite), functional (needle point tracing), graphic (arrow point tracing), and radiographic. The graphic method uses a central bearing device to trace mandibular movements and aims to produce an arrow-shaped tracing. Eccentric relations include protrusive and lateral jaw positions which are recorded to reproduce mandibular movements in the articulator.

1. BY-AVANTIKA BOHRA
Final YEAR

2. HORIZONTAL JAW RELATION
Horizontal jaw relation is the
maxillomandibular relation in a horizontal
plane.
Described as relationship of mandible to
maxilla in the anteroposterior direction.
2 TYPES:
1) CENTRIC jaw relation
2) ECCENTRIC jaw relation

3. CENTRIC RELATION

4. • 3 primary requirements:
1. To record the correct horizontal
relationship of mandible to maxilla
2. To exert equalized vertical pressure
3. To retain record in undistorted condition
until the cast have been accurately
mounted on articulator

5. METHODS TO RECORD CENTRIC RELATION:
 PHYSIOLOGICAL
• tactile or inter occlusal check record method
• Pressureless method
• Pressure method
 FUNCTIONAL
• Needle house method
• Patterson method
 GRAPHIC
• Intra oral
• Extra oral
 RADIOGRAPHIC METHOD

6. Physiologic method
• Based on:
o Proprioceptive impulse of patient
o Kinesthetic sense or muscle sense helps to direct
movements of parts of the body of the body
o Visual acuity and sense of touch of patient
1) Tactile sense or inter occlusal check record
method.
Tentative jaw relation is recorded.
Ask the patient to retrude the mandible.
Casts are articulated based on this tentative record

7. INDICATIONS
 Abnormally related jaws.
 Displaceable flabby tissue.
 Large tongue
 Uncontrolled mandibular movements.
 In patients already using a complete
denture

8. • Material used
1. Waxes: low fusing
2. Impression compound
3. Dental plaster
4. ZOE paste

9. PROCEDURE:
a) Recording tentative jaw relation:
• Maxillary occlusal rim inserted to patients
mouth.
• Vertical dimension at rest is
established.mandibular occlusal rim
inserted and reduced accordingly,
• Tentative centric relation recorded using
tentative jaw relations.artificial teeth are
arranged.

10. b) Making the inter occlusal check record.
• Upper and lower trial dentures are inserted
into the mouth.keep a piece of cotton to
prevent contact of opposing members.
• Aluwax is added on the occlusal surface of
teeth of mandibular occlusal rim
• Patient asked to retrude mandible and close
on the wax till tooth contact occurs.
• Trial dentures removed and allowed to cool.

12. Recording centric relation

13. Mounting of the casts

14. 2)Static or pressureless method.
Nick notch method:
• Patient asked to retrude mandible in position.
• Upto 3mm of wax removed from mandibular
occlusal rimfrom the premolar region till the distal
end
• 1 or 2 notches are cut on the corresponding area
of maxillary occlusal rim.
• One nick is cut anterior to the notch,a V shaped
valley
• Nick:prevent lateral movement
• Notch: anteroposterior movement

15. • Nick and notch are lubricated with petroleum.
• Prepared occlusal rim are inserted into
patient’s mouth and taught to close his
mandible in maximum retruded position.
• Aluwax is placed on the trough created in
mandibular rim.
• Mandibular occlusal rim is cooled and
inserted into patients mouth and closed in
centric relation.

18. 3)Pressure method
• Establish vertical dimension.
• Upper occlusal rim inserted.lower occlusal
rim is fabricated by softening in water
bath.
• Insert it into patients mouth.
• Patient asked to close mouth in centric
relation on soft wax in predetermined
vertical dimension and then articulated.

20. Functional method
• Method utilise the the functional movements of jaws to record the
centric relation.
• Patient asked to perfprm border border movements such as
protrusive and lateral excersion movement.
a) Needle house method
• Fabrication of occlusal rim made from impression compound
• Four metal beads or styli are embedded into premolar and molar
areas of maxillary occlusal rim.
• Occlusal rim inserted into patients mouth and asked to close
occlusal rim and make protrussive,retrussive ,right and left
movement of mandible.
• When movements are made “diamond shaped marking pattern
rather than a line is formed on the mandibular occlusal rim.

21. • Patient produces mandibular movements
by moving mandible to protrusion ,
retrusion, right and left lateral

23. Graphic method
• The graphic method record a tracing of
mandibular movements in one plane
• 2 types:
1) Arrow point tracing
2) Pantograph
Arrow point tracing is a graphic record
measured across single plane
Pantogaph is measured three dimensionally.

25. Factors to be considered while
carrying out tracing
1. Stability of denture base
2. Resistance of rims
3. Difficulty in placing central bearing device
4. Height of residual alveolar ridge
5. Tongue interferance
6. Efficiency of recording device
7. Lack of coordinated movements

26. Arrow point tracing or gothic arch
tracer
• Made using gothic arch tracers
• Recorded in horizontal plane.
• Consists of central bearing device:a device that provide
central point of bearing or support between the
maxillary & mandibular dental arches.
consists of contacting point attached to one dental arch
and plate attached to opposing dental arch
Plate provide surface on which the tracing of
mandibular movements is recorded.
Consists of:CENTRAL BEARING POINT & CENTRAL
BEARING PLATE.

27. Types of arrow point tracings
• Typical
• Flat
• Asymmetric

28. • Absent apex
• Miniature tracing
• Double arrow point

29. • Dorsally extended arrow point
• Interrupted form
• Atypical form

33. • TYPES OF ARROW POINT TRACERS:
1) INTRA ORAL TRACING POINT:
• Central bearing device is located intra orally.
• Tracer is placed within the mouth.
• Central bearing point & plate is inserted into patients
mouth.
• Central bearing point is adjusted such that it contact
the central bearing plate at predetermined vertical
dimension.
• Ask to make anteroposterior and lateral movements.
• Central bearing point will draw the tracing pattern on
central bearing plate
• Tracing should resemble an arrow point with a sharp
apex.

35. Points to be considered while doing
graphic tracing method
1. Displacement of record base may result
from pressure if central bearing points is off
center when mandible moves in eccentric
relation to maxilla
2. If central bearing device is not used the
occlusal rims offer more resistance to
horizontal movements
3. Difficult to stabilize record base against
horizontal forces on tissue that are
pendulous

36. 4. Difficult to stabilize record base against
horizontal forces on residual ridges that
have no vertical height
5. Difficult to stabilize record base with pt
who have awkward tongues
6. Recording device are not usually
considered compactible with physiologic
stimulation in mandibular movements
7. Tracing is not accepted unless a pointed
apex is developed

37. 8. Double tracing-lack of coordinated
movement
9. It is made at predetermined vertical
dimension of occlusion.this harmonius
centric relation with centric occlusion and
anteroposterior bone –bone relation with
tooth-tooth contact
10.Graphic method can reecord eccentric
relation of mandible to maxilla
11.Most accurate means

39. ECCENTRIC JAW RELATION
• “any relationship of mandible to maxilla other
than centric relation”
• Include protrusive and lateral relations.
• Help to adjust the lateral and horizontal
condylar inclination in the articulator.
• Thus helps the articulator to reproduce
eccentric movements of mandible and
establish balanced occlusion.
• Recorded using functional or tactile method.

40. Lateral jaw relations
• Common methods:
• Graphic method
• With check bites of wax
• With positional records of stone/plaster
• Pantography
• Hanau’s formula:
• L = H/8 + 12
L=lateral condylar inclination
• H=Horizontal condylar inclination