Posterior: R&L TMJ Anterior: Teeth Neuromuscular system

2. Refrences
Fundamentals
of fixed
prosthodontics
(2012)
Chap 2

3. CR (optimum condylar position)

5. Anatomy of the TMJ

6. The Determinants of Mandibular Movement
Posterior: R&L TMJ
Anterior: Teeth
Neuromuscular system

7. TEETH
CR
MI
CR=MI???
CRǂMI???

8. LEVER SYSTEM OF MANDIBLE

9. Normal Versus Pathologic Occlusion
Physiologic or normal occlusion
Pathologic Occlusion
Sign & symptom

10. Optimum occlusion
1. In closure, the condyles are in the most
superoanterior position.
The posterior teeth are in solid and even contact,
and the anterior teeth are in slightly lighter contact.
2. Occlusal forces are in the long axes of the teeth

11. Organization of the Occlusion
• Bilateral Balanced Occlusion
• Unilateral Balanced Occlusion
• Mutually Protected Occlusion
Canine protected
''organic" occlusion

12. Optimum occlusion
3. In lateral excursions, working-side disocclude or
separate the nonworking teeth instantly.
4. In protrusive excursions, anterior tooth contacts will
disocclude the posterior teeth.
5 In an upright posture, posterior teeth contact more
heavily than do anterior teeth.

14. Bilateral Balanced Occlusion
• Spee and Monson (prosthodontic concept)
• Complete denture
• complete occlusal rehabilitation???

15. Unilateral Balanced Occlusion
(group function)
• All teeth on the working side to be
in contact
• distributes the occlusal load

16. Mutually Protected Occlusion
• Gnathological concept
• Canine protected occlusion
• ''organic" occlusion

17. Effects of Anatomic Determinants
• Molar Disocclusion
• Condylar Guidance
• Anterior Guidance

18. Molar Disocclusion
• flexible nature of the articular disc
• 0.2 mm in centric relation
• 0.3mm in working
• 0.8 mm in both protrusive and nonworking

19. • Average separation
• 0.5 mm in working
• 1.0 mm in nonworking
• 1.1 mm in protrusive

20. Condylar Guidance
• Protrusive condylar path inclination
• Mandibular lateral translation (Immediate
mandibular lateral translation)

21. Protrusive condylar path inclination
30.4 degrees
If steep: cusp height maybe longer
If shallow: cusp height must be shorter

22. Immediate lateral translation
• If great: cusp height must be shorter
• If minimal: cusp height maybe made
longer.

23. • nearer to the working side condyle

25. Anterior Guidance
• protrusive incisal path
• protrusive incisal path inclination(50
to 70 degrees)

26. vertical and horizontal overlap
• OB˃˃ posterior cusp height may be
longer
• OJ˃˃ posterior cusp height must be
shorter