jaw relation records

1. Jaw relations in
complete dentures
Dr. M. Pavan Preetham
Reader
Dept. of Prosthodontics
SB Patil Institute for Dental Sciences & Research
Bidar

2. Recording of jaw relations in the treatment of edentulous patients aims at
facilitating the adaptation of the complete denture to the masticatory
system to give them an optimal and comfortable function.
To achieve this goal, the recording must include an approximate vertical
dimension of occlusion, stable occlusal contacts in harmony with the existing
TMJ and masticatory muscle functions.

3. Types
• Orientation relation
• Vertical relation
• Horizontal relation
• centric relation
• eccentric relation—
• protrusive records
• lateral records.

4. Clinical significance
• To re-establish the functional position of the mandible.
• Comfort
• Esthetics
• Phonetics
• Functional efficiency
• Structural balance.

5. Upper bite rim
• Labial fullness-
• The lip is normally supported by
the alveolar process and teeth
• represented by the base and rim
of the record block.

6. Upper bite rim
• Height
• approximately 3mm of upper
central incisors when the lips
are just parted

7. Upper bite rim
• Anterior Plane
• parallel to an imaginary line
joining the pupils of the eyes or
a line at right angles to the
midsagittal plane of the face

8. Upper bite rim
• Antero posterior Plane
• parallel to Ala-tragus line (an
imaginary line running from the
external auditory meatus or
tragus of the ear to the lower
border of ala of the nose)

9. The midline
• an imaginary line from the centre of the
brows to the centre of the chin.
• Immediately below the centre of the
philtrum
• Immediately below the centre of the
labial tubercle

10. Canine line
• mark the corners of the mouth
when the lips are relaxed
• are supposed to coincide with the
tips of the upper canine teeth but
are only arbitary
• These lines give some indication of
the width to be taken up by the
six anterior teeth from tip to tip
of the canines

11. Lower bite rim
• Trim the lower block so that it occludes evenly with the upper
• The location of the occlusal plane posteriorly will ultimately be
determined by the height of the mandibular anterior teeth and
anterior 2/3rd of retromolar pads.

12. Orientation jaw
relation

13. • Orientation relations are those that orient the mandible to the cranium
in such a way that when the mandible is kept in its most posterior
unstrained position, the mandible can rotate in the sagittal plane around
an imaginary transverse axis passing through or near the condyles

14. Facebow
A caliper like instrument used to record the
spatial relationship of the maxillary arch to
some anatomic reference point or points and
then transfer this relationship to an articulator
it orients the dental cast in the same
relationship to the opening axis of the
articulator.
Types of Face bow:
KINEMATIC face
bow
ARBITRARY face
bow
• Facial type
• Earpiece type

15. Vertical jaw
relation

16. • The vertical dimension of face b/w any two arbitrary selected
points located one above and one below the mouth, usually in the
midline.
• 1) Vertical dimension of occlusion
• 2) Vertical dimension of rest
• 3) Vertical dimension in the other positions.

17. VDO
• The distance b/w two points when the occluding
members are in contact.
OR
• It is the relation of the mandible to the maxilla
when the occlusal stops are provided by the
teeth/occlusion

18. VDR
• The distance b/w two selected point measured
when the mandible is in the physiologic rest
position.

19. Vertical dimension in speech
• Difference b/w the resting vertical
dimension and vertical dimension of
occlusion.
• First studied by Dr.M E Niswonger
• 2-4mm.

20. Factors to be considered in VD
• Position of mandible – influenced by gravity
• Patient should be calm, cool, & relaxed
• Difficult in neuromuscular disturbances

21. Methods of recording VD
Mechanical
• Ridge relation
• Old dentures
• Facial measurements
Physiologic
• Phonetics
• Tactile
• Esthetics

22. Niswonger’s
method

23. Increased VD
Increased risk of trauma Clenching of teeth.
Discomfort to patient
teeth are liable to contact – causing clicking during speech
Trauma & pain – basal seat areas of denture
Loss of freeway space muscular fatigue
Clicking sound
Elongated appearance of face
Bone resorption
Loss of retension & stability of dentures
Generalised hyperemia

24. Decreased VD
Reduced masticatory efficiency
Poor esthetics
Cheek biting/ tongue biting/ lip biting
Denture look
Angular chelitis
Pain in TMJ
Coston’s syndrome-push the tongue towards the throat
eustachian blockage
prognathism

25. Horizontal jaw
relation

26. Horizontal
jaw relation
Centric
relation
•Protrusive record
•Lateral record
Eccentric
relation