1. Horizontal jaw relations
Vinay PavanKumar . K
1st year MDS student
Department of Prosthodontics
AECS Maaruti Dental College
2.
3. Jaw Relation
• It is described as any spatial relationship of the
mandible to the maxilla
4. Horizontal jaw relation
• Horizontal Jaw relation is the relationship of the
mandible to the maxilla in a horizontal plane or it is
the relationship of the mandible to the maxilla in an
antero-posterior direction.
6. Centric relation
The most retruded relation of the mandible to the
maxilla when the condyles are in the most
posterior unrestrained position in the glenoid
fossa from which lateral movements can be
made, at any given degree of jaw separation.
7. GPT-8
• A maxillomandibular relationship in which the
condyles articulate with the thinnest avascular
portion of their respective disks with the complex in
the anteriorsuperior 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 about a transverse horizontal axis.
8.
9. Purpose of recording centric relation
• It is a bone to bone relation and it is constant
• It is repeatable and recordable and thus serves as a
reliable guide for developing centric occlusion in
complete dentures
• It is related to the terminal hinge axis ,in CR condyles
exhibit pure rotation without any translation
10. • Functional movements like chewing and swallowing can
be carried out since it is the most unstrained position.
Final act of masticatory stroke ends in centric relation
• Reference relation
• It is more definite than vertical relation since it is
independent of tooth contact
11. Criterias for mandible to be in centric
• Disk properly aligned on both condyles
• Condyle-disk assembly at the highest point against the
posterior slopes of eminentia
• Medial pole of condyle-disk assembly braced by bone
12. Theories of centric relation
• The Muscle theory
• The Ligament theory
• The Osteofiber theory
• The Meniscus theory
Saizer P. Centric relation and condylar movement: anatomic
mechanism. J Prosthet Dent 1971;26(6):581-91.
14. The Ligament theory
• Bind the elements of the
articulation
• Lateral radiographic views
• ‘Suspended’ or ‘Floating’
condyle
• Anatomic arrangement- not
well suited to halt retrusive
movement
15. The Osteofiber theory
• Meyer
• Fibrous stop - buffer
• Retroarticular cushion
• retrusive terminal stop
16. The Meniscus theory
• The posterosuperior surface unfolds along the roof of the
glenoid fossa
• Discs with their retromeniscal fibrous tissues--stop the
retrusive condylar movements
17. Factors influencing centric relation records
• The resiliency of the supporting tissues
• Fit of the denture bases
• Residual alveolar arch
• Saliva
• Tongue
Yurkstas AA, Kapur KK. Factors influencing centric relation
records in edentulous mouths. J Prosthet Dent 2005;93:305-10.
18. • The health and cooperation of the patient
• The posture of the patient
• The temporomandibular joint and its associated neuromuscular
mechanisms
• The skill of the dentist
• Pressure applied in making the recording
• The technique used and the recording devices used
20. Methods of assisting the patient to retrude
the mandible
• Let the jaw relax, pull it back and
close slowly on the posterior teeth
• Push the upper jaw out and close
on the back teeth
• Protrude and retrude the mandible
repeatedly
21. Roll the tongue backwards towards the posterior border
of upper denture and close the rims until they meet
Bissasu M. Use of the tongue for recording centric relation for
edentulous patients. J Prosthet Dent 1999;82:369-70.
23. Recording the Centric relation
• Primary requirements -
• accuracy
• equalized vertical pressure
• recording medium - uniform consistency
• retain the record in an undistorted condition
24. Pressure used while recording the centric relation
• Minimum closing pressure Opposing teeth to
touch uniformly and simultaneously at their first
contact
• Heavy closing pressure To produce same
displacement of the soft tissues as on the
dentures during function
25. Methods used for recording centric relation
• Tactile or interocclusal check record method
• Functional (chew-in) methods
• Meyer’s method
• Patterson’s method
• Needles-House method
• Excursive (graphic) methods
• Intraoral tracing
• Extraoral tracing
26. • Terminal hinge axis method
• Other methods
• Deglutition
• Pantography
27. Tactile or interocclusal check record method
• Philip Pfaff – “biscuit bite”
• Patient’s proprioception and tactile sense
• Indications:
• abnormally related jaws
• excessively displaceable supporting tissues
• large tongue
• abnormal mandibular movements
• verify occlusion in existing dentures
28. Interocclusal check record can be made-
• Between upper and lower rims
• Between upper and lower artificial or natural
teeth
• Between a central bearing plate and pin
30. Technique
• Two steps-
• Tentative records using occlusion rims
• Interocclusal check records with the teeth
arranged for try-in
• Anterior try-in
• Posterior try-in
51. Physiologic Centric Relation (Shanahan)
• Swallow and hold
Shanahan TEJ. Physiologic jaw relations and occlusion of
complete dentures. J Prosthet Dent 2004;91(3):203-05.
52. • Verification after denture fabrication
• 30-gauge wax
Shanahan TEJ. Physiologic jaw relations and occlusion of
complete dentures. J Prosthet Dent 2004;91(3):203-05.
53. Centric-relation recording techniques
• Swallowing or free closure (Shanahan)
• Chin point guidance
• Chin-point guidance with anterior jig
• Bilateral manipulation
Kantor ME, Silverman SI and Garfinkel L. Centric-relation recording
techniques-a comparative investigation. J Prosthet Dent 1972;28(6):593-
600.
54. Chin point guidance
• Chin-point guidance with
anterior jig
• Bilateral manipulation
55. Median variability
• Swallowing or free-closure records - 0.40 mm
• Chin-point guidance - 0.14 mm
• Chin-point guidance with an anterior jig - 0.07 mm
• Bilateral manipulation - 0.05 mm
56. Pantography
• Used clinically to measure mandibular movement
• Graphic record in three planes
• Types-
• Mechanical (by McCollum and Staurt)
• Electronic
63. Lateral jaw relations
• Influence the intercuspation of teeth in working
mastication
• Used to program the articulator
64. Lateral interocclusal records (Whip mix)
• Set side shift guide at 45o
• Mark 6mm from centric relation along Left Lateral
tracing and centre the hole of plastic piece over it
• Right condylar ball is in protrusion
• Side shift guide brought in contact with the ball
65. Lateral interocclusal records (Hanau)
L = H/8 + 12
( H – Horizontal condylar inclination
L – Lateral condylar inclination)
66. Clinical protocol
Nair CK. Programming the semiadjustable articulator. Trends in
Prosthodontics 2011;2(1):12-14.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80. Protrusive records made of plaster at 2mm, 4mm,
6mm, 8mm and 10mm
Nair CK et al. Relationship between protrusive record and horizontal
condylar guidance angle. Trends in Prosthodontics 2011;2(1):15-16.
81. Programming the articulator using interocclusal records
to note variation in the condylar guidance angle
Nair CK et al. Relationship between protrusive record and horizontal
condylar guidance angle. Trends in Prosthodontics 2011;2(1):15-16.
82. Nair CK et al. Relationship between protrusive record and horizontal
condylar guidance angle. Trends in Prosthodontics 2011;2(1):15-16.
Right condyle
( Mean ±SD)
Left condyle
( Mean ±SD)
2mm 7.083o±5.42o 10.42o ± 7.22o
4mm 14.17o ± 6.56o 17.08o ± 10.97o
6mm 18.75o ± 5.28o 22.5o ± 8.66o
8mm 18.33o ± 3.89o 18.75o ± 5.69o
10mm 11.25o ± 4.33o 14.58o ± 5.42o
83. References:
Nair KC, A primer on complete denture fabrication,
1st edition, 2013, Ahuja publication, India Pp 67-77
Winkler S, Essentials of Complete Denture
Prosthodontics, 2nd edition, India, A.I.B.T.S
Publishers and distributors, 2009, pp 192-201.
Sharry JJ, Complete Denture Prosthodontics, 3rd
edition, USA, Mcgraw-Hill Book Company, 1974,
pp 215-222.
84. Manappallil JJ, Complete Denture Prosthodontics,
1st edition, India, Arya (Medi) Publishing House,
2006, pp 145-67, 181-83, 194-98.
Saizer P. Centric relation and condylar movement:
anatomic mechanism. J Prosthet Dent
1971;26(6):581-91.
Avant WE. Using the term centric. J Prosthet Dent
1971;25(1):12-15.
85. Yurkstas AA, Kapur KK. Factors influencing centric
relation records in edentulous mouths. J Prosthet
Dent 2005;93:305-10.
Shanahan TEJ. Physiologic jaw relations and
occlusion of complete dentures. J Prosthet Dent
2004;91(3):203-5.
Kantor ME, Silverman SI and Garfinkel L. Centric-
relation recording techniques-a comparative
investigation. J Prosthet Dent 1972;28(6):593-600
86. Kingery RH. A review of sone of the problems
associated with centric relation. J Prosthet Dent
1952;2(3):307-19.
Bissasu M. Use of the tongue for recording centric
relation for edentulous patients. J Prosthet Dent
1999;82:369-70.
Gothic arch tracing ppt.
87. Nair CK. Programming the semiadjustable
articulator. Trends in Prosthodontics 2011;2(1):12-
14.
Nair CK et al. Relationship between protrusive
record and horizontal condylar guidance angle.
Trends in Prosthodontics 2011;2(1):15-16.