1. DENT 5315/DH 2215 March 4, 2008 Here comes the Quiz! Yes!

2. KEY

3. Temporomandibular Joint Dr. Sandra Myers Director, NIDCR’s TIRR TMJ Implant Repository National Institute of Dental and Craniofacial Research's TMJ Implant Registry and Repository

4. Splints Patient slides deleted to protect patient identity.

5. Temporomandibular Joint (TMJ) I.Classification of Joints II.Temporomandibular Joint

6. I. Classification of Joints 3 Types of Joints: A.Fibrous B.Cartilaginous C.Synovial

7. I. Classification of Joints

8. II. Temporomandibular Joint (TMJ) A.Type of Joint B.Development C.Anatomy & Histology D. Biomechanics E. Innervation F. Blood Supply

9. II. Temporomandibular Joint (TMJ) A.Type of Joint “synovial sliding- ginglymoid joint” Ginglymoid means: Pertaining to, or resembling, a ginglymus, or hinge joint; ginglyform.ginglymushinge ginglyform

10. II. Temporomandibular Joint (TMJ) B.Development Association of Meckel’s cartilage with mandible Condylar cartilage appears 12th week

11. II. Temporomandibular Joint (TMJ) C.Anatomy & Histology

12. Condylar Head Bovine Condyle

13. Condylar Head A - Fibrous layer B - Reserve zone C - Proliferative zone D - Hypertrophic zone E - Calcifying zone F - Bone

14. Capsule Functions:  Seals joint space  Passive stability  Synovial lining  Proprioceptive nerve endings Note synovial membrane over villi (arrow):

15. Articular Disk “Acres of Collagen” Aneural & Avascular

16. Posterior Ligament

17. Synovial Membrane Synovial Fluid:  Liquid environment  Lubrication  Nutrition?

18. Muscles Muscles of Mastication Difference between unipennate, bipennate & multipennate: Muscles with central tendon Muscle fiber bundles attached to one side, two sides or around multiple central tendons

19. D. Biomechanics Complex combinations of muscle activity Disk enables complex movements

20. D. Innervation Movements of synovial joint initiated & effected by muscle coordination. Achieved in part through sensory innervation. Hilton’s Law: The muscles acting on a joint have the same nerve supply as the joint. Therefore: Branches of the mandibular division of the fifth cranial nerve supply the TMJ (auriculotemporal, deep temporal, and masseteric)

21. D. Innervation 4 Types of nerve endings: 1. Ruffini’s corpuscles (limited to capsule) 2. Pacini’s corpuscles (limited to capsule) 3. Golgi tendon organs (confined to ligament) 4. Free nerve endings (most abundant)

22. Pacinian Corpuscle http://www.kumc.edu/instruction/medicine/anatomy/hi stoweb/nervous/nervous.htm “Onion-like encapusulated pressure receptors Surrounding concentric lamellae respond to distortion, generate action potential in unmyelinated fiber in core Bar = 100 microns

23. Ruffini’s & Golgi Corpuscle Function: Ruffini’s = Posture (proprioception), dynamic and static balance Golgi tendon organ = Static mechanoreception, protection (ligament) Free nerve endings = Pain (nociception) protection (joint) www.anatomyatlases.org/ MicroscopicAnatomy/Section06/ Section06.shtml Ruffini’s Corpuscle