Horizontal jaw relation in complete denture

jaw relation, horizontal jaw relation, gothic tracing, programming of semi adjustable articulators (hanau)

1. Horizontal jaw relations Vinay PavanKumar . K 1 st year MDS student Department of Prosthodontics AECS Maaruti Dental College

2. Horizontal jaw relation Centric relation Clinical protocol Eccentric relation Protrusive Lateral Theories Methods of recording Functional Physiological Graphic

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.

5. Centric relation Eccentric relation Protrusive relation Lateral relation Left lateral Right lateral It can be of two types

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. 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

9. 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

10. 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

11. 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 .

12. The Muscle theory Defense reflex External pterygoid muscles contracts Halts the jaw

13. 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

14. The Osteofiber theory Meyer Fibrous stop - buffer Retroarticular cushion retrusive terminal stop

15. 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

16. 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.

17. 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

18. Difficulties in obtaining mandibular retrusion Biologic difficulties Mechanical difficulties Psychological difficulties

19. 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

20. 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.

21. Boos stretch-relax exercises Tilting the head backwards Swallow and close

22. Recording the Centric relation Primary requirements - accuracy equalized vertical pressure recording medium - uniform consistency retain the record in an undistorted condition

23. 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

24. 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

25. Terminal hinge axis method Other methods Deglutition Pantography

26. 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

27. 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

28. Bite registration/recording materials Waxes Quick setting plaster Impression compound Bite registration paste ( ZnO -E) Bite registration silicone

29. Technique Two steps- Tentative records using occlusion rims Interocclusal check records with the teeth arranged for try-in Anterior try-in Posterior try-in

30. Seat the patient with head upright

31. Nick and Notch method Too shallow 2 mm

32. Bite registration material

33. Recording centric relation

34. Mounting of the casts

35. Stapler pin method

36. Functional (chew-in) methods Meyer’s method Patterson’s method Needles-House method Meyer’s method Soft wax - generated path Plaster index - set the teeth

37. Patterson’s method Wax occlusal rims Mixture of half plaster and half carborundum in the trench Compensatory curve

38. Needles-House method Compound occlusion rims Four metal styli Diamond-shaped tracings

39. Excursive (graphic) methods Gothic arch tracing Arrow point tracing Tracing in one plane Apex - the most retruded position

40. Uses- Verify centric relation Obtain protrusive and lateral records Types- Intraoral tracer Extraoral tracer

41. Intraoral tracing assembly

42. Intraoral tracing

43. Extraoral tracing ( Hight tracing device)

44. Extraoral tracing

45. Types of arrow point tracings Typical Flat Asymmetric

46. Absent apex Miniature tracing Double arrow point

47. Dorsally extended arrow point Interrupted form Atypical form

48. Terminal hinge axis method An imaginary line around which the mandible may rotate without translatory movement.

49. Other methods- Deglutition Pantography Deglutition Physiologic method ‘swallow and hold’

50. 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.

51. 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.

52. 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.

53. Chin point guidance Chin-point guidance with anterior jig Bilateral manipulation

54. 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

55. Pantography Used clinically to measure mandibular movement Graphic record in three planes Types- Mechanical (by McCollum and Staurt ) Electronic

56. Pantographic tracings

57. Eccentric relation records Protrusive relation Lateral relation Left lateral Right lateral

58. Protrusive jaw relation Register the influence of the condylar paths over the movements of the mandible Christensen’s phenomenon

59. Protrusive interocclusal record (Whip mix)

60. Protrusive interocclusal record (Hanau)

61. Lateral jaw relations Influence the intercuspation of teeth in working mastication Used to program the articulator

62. Lateral interocclusal records (Whip mix) Set side shift guide at 45 o 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

63. Lateral interocclusal records (Hanau) L = H/8 + 12 ( H – Horizontal condylar inclination L – Lateral condylar inclination)

64. Clinical protocol Nair CK. Programming the semiadjustable articulator. Trends in Prosthodontics 2011;2(1):12-14.

65. 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.

66. 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.

67. 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 7.083 o ±5.42 o 10.42 o ± 7.22 o 4mm 14.17 o ± 6.56 o 17.08 o ± 10.97 o 6mm 18.75 o ± 5.28 o 22.5 o ± 8.66 o 8mm 18.33 o ± 3.89 o 18.75 o ± 5.69 o 10mm 11.25 o ± 4.33 o 14.58 o ± 5.42 o

68. 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 , 2 nd edition, India, A.I.B.T.S Publishers and distributors, 2009, pp 192-201. Sharry JJ, Complete Denture Prosthodontics , 3 rd edition, USA, Mcgraw -Hill Book Company, 1974, pp 215-222.

69. Manappallil JJ, Complete Denture Prosthodontics , 1 st 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.

70. 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

71. 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.

72. 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.