Download to read offline
Uploaded byDr. Piyush Karn
Temporomandibur joint
The temporomandibular joint is a synovial joint that connects the mandible to the temporal bone. It is a modified hinge joint that allows for depression and elevation of the mandible as well as protrusion, retraction, and side-to-side movements during chewing. The joint is comprised of the articular tubercle of the temporal bone above and the condyle of the mandible below. An articular disc divides the joint cavity into two compartments. Various ligaments and muscles are involved in stabilizing the joint and producing its movements.
More Related Content
Similar to Temporomandibur joint
Temporomandibur joint
- 1.
- 2. • Introduction • Classification/type • Articulating Bony surfaces • Ligaments • Factors which maintain stability of joint • Associated structures (like bursa, tendinous cuff) • Relations of joint • Blood supply • Nerve supply • Movements/ Biomechanics • Applied anatomy How to write answer for any Joint ? Headings
- 3. INTRODUCTION • ARTICULATION OF MANDIBLEWITH SKULL. • PAIRED IN THE FORM OF BICONDYLAR ARTICULATION. • SYNOVIAL JOINT OF MODIFIED HINGE VARIETY • *GINGLYMOARTHRODIA L JOINT.
- 6. • Articulating Bones •Above: Temporal bone (Articular tubercle & anterior articular part of mandibular Fossa. • Below: Head / Condyles of mandible ( elliptical- axis perpendicular to the plane of ramus of mandible.)
- 11. • Articulating surfacescovered by Fibrocartilage • Joint cavity divided by articular disc into 2 compartments: • upper menisco-temporal compartment • lower menisco-mandibular compartment.
- 13. • Ligaments: • Capsularligament • Articular disc • Lateral Ligament / temporo-mandibular ligament. • Acessory ligaments: Sphenomandibular & stylomandibular Ligament.
- 15. • Relations: • Anterior:Lateral pterygoid, Temporalis & Masseteric vessels & nerve. • Posterior: Parotid,Superficial temporal vessels, Auriculotemporal nerve, Ext. Acoustic meatus. • Lateral: It is Subcutaneous. • Medial: Lateral pterygoid, Roots of Auriculotemporal nerve enclosing Middle meningeal Artery, Spine of shenoid and sphenomandibular ligament , Chorda tympani nerve.
- 19.
- 25. • Arterial supply:Branches of Superficial temporal And Maxillary Arteries • Nerve Supply: Auriculotemporal nerve & Masseteric nerve.
- 26. • Movements: • Protrusion •Retraction • Depression • Elevation • Side to side chewing movements.
- 27. • Muscle ProducingMovements • Protrusion: Simultaneous action of Lat. & Med. Pterygoid. • Retraction: Posterior fibres of Temporalis • Depression: Lateral pterygoid, Geniohyoid, Mylohyoid, Digastric; Gravity. • Elevation: Masseter, Temporalis & Medial Pterygoid. • Side to side Chewing: Lateral &Medial pterygoid acting alternately with other side.
- 31. • Range ofMovements: • Depression/ mouth opening: 5 cm • Protrusion: 1cm • lateral displacement: 1cm
- 32. • Mechanism: • Meniscotemporalcompartment permits gliding for protrusion, retraction and chewing movements. • Menisco mandibular compartment permits rotatory movement. • Axis: • a) transverse axis for depression and elevation • b) vertical axis for Side to side movement.
- 33. • Mechanism ofmouth opening: • Head of mandible And articular disc together glide forward in menisco temporal compartment by action of Lat pterygoid. • Simultaneously rotation of head occurs in lower compartment by suprahyoid muscles.
- 34. • 3 phase: •Initial phase (Rotation): rotation of mandibular head in lower compartment. Axis transverse through neck • Intermediate phase (Rolling): gliding forward of head as well as articular disc in upper compartment. Head keeps on rotating in lower compartment. Axis moves forward. gliding arrested by posterior fibres of temporalis. • Final phase (Rotation): Axis fixed and head rotates further in lower compartment until it reaches summit of articular tubercle.
- 36. • Mechanism ofchewing: • Mandibular head of one side glides forward in upper compartment & Rotation occurs in lower compartment. • Axis being the vertical axis passing posterior border of opposite ramus. • Head then returns to its normal position and opposite head repeats the movement.
- 38. • Factors ofStability: • Bones: Forward displacement prevented by Articular tubercle. • Backward displacement prevented by Post glenoid tubercles. • Ligaments :temporo mandibular ligament prevents Backward displacement • Muscles: Temporalis limits protrusion. Lateral pterygoid limits retraction. • Position of mandible: Occlusal position is the Close pack position.
- 39. Applied • Dislocation: onlyForward dislocation is seen. Head dislocated to infratemporal fossa • Reason: Sudden spasm of Lat pterygoid during wide opening (Yawning) • Reduction: downward traction with chin elevation.
- 42.