TMJ Anatomy and Dislocation PDF

Here is the content in a structured table format for clarity: | **Topic** | **Details** | |---------------------------...

Here is the content in a structured table format for clarity: | **Topic** | **Details** | |-------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------| | **Introduction** | - Overview of TMJ, bones, joints, muscles of mastication, jaw dislocation, and resolution. | | | - Bones: Temporal, sphenoid, zygomatic, maxilla, mandible. | | **Mandible** | - **Superior processes**: Condyloid process, coronoid process; separated by mandibular notch. | | | - **Other parts**: Neck, ramus, angle, body. | | | - **Foramina**: Mental foramina (sensory innervation by mental nerves, branches of inferior alveolar nerve, mandibular division of trigeminal nerve). | | | - **Internal aspects**: Mandibular foramina (entry of inferior alveolar nerve into mandibular canal), submandibular fossa (houses submandibular gland). | | **Temporal Bone** | - **Mandibular fossa**: Articulates with condyloid process. | | | - **Landmarks**: Articular tubercle (or eminence), external auditory meatus, mastoid process, styloid process. | | **Temporomandibular Joint (TMJ)** | - **Type**: Synovial joint; articulation between condyloid process and mandibular fossa. | | | - **Compartments**: Articular disc divides joint into upper (gliding movements like protrusion/retraction) and lower (rotational movements like elevation/depression).| | | - **Movements**: Jaw depression requires anterior movement of the condyloid process. | | | - **Dislocation**: Occurs if the condyloid process moves beyond the articular tubercle. | | **TMJ Ligaments** | - **Lateral ligament**: Limits posterior movements; attaches to zygomatic arch and posterior neck of mandible. | | | - **Medial ligaments**: Sphenomandibular (ramus to sphenoid bone) and stylomandibular (ramus to styloid process) limit lateral movements. | | **Muscles of Mastication** | - **Medial Pterygoid**: Two heads (deep attaches to medial side of lateral pterygoid plate; superficial attaches to maxilla/palatine bones). | | | - **Lateral Pterygoid**: Two heads (superior attaches to roof of infratemporal fossa; inferior attaches to lateral side of lateral pterygoid plate). | | | - **Temporalis**: Fan-shaped; arises from temporal fossa; attaches to coronoid process; assists in jaw closure and retraction. | | | - **Masseter**: Two heads (superficial and deep); attachments: zygomatic bone and arch to ramus/angle of mandible; elevates mandible for closure. | | | - **Innervation**: All muscles by mandibular division of trigeminal nerve. | | **Jaw Dislocation** | - **Mechanism**: Anterior dislocation involves the condyloid process moving beyond the articular tubercle; muscles of mastication spasm. | | | - **Resolution**: Apply downward pressure on molars and guide mandible back into mandibular fossa. | | **Summary** | - TMJ: Synovial joint, upper and lower compartments for gliding/rotational movements. | | | - Most stable when jaw is closed. | | **Feedback Request** | - Encourages viewers to provide feedback or suggest future topics. | Let me know if you'd like additional refinements or diagrams for better understanding!