TEMPORAL AND INFRATEMPORAL REGIONS .pptx

this is the detailed presentation about TMJ and nerves related to it most useful for dental students.

1. TEMPORAL AND INFRATEMPORAL REGIONS By Sai Mahendra Varma

2. TEMPORAL FOSSA INFRA TEMPORAL FOSSA MUSCLES OF MASTICATION MAXILLARY ARTERY TEMPORO MANDIBULAR JOINT MANDIBULAR NERVE OTIC GANGLION

3. TEMPORAL FOSSA IT LIES ON SIDE OF SKULL AND IS BOUNDED BY TEMPORAL LINE AND ZYGOMATIC ARCH BOUNDARIES: ANT: Zygomatic and frontal bones POST: Inf temporal line and supra mastoid crest SUP: Superior temporal line INF: Zygomatic arch FLOOR: parts br.of frontal , temporal and greater wing of sphenoid . temporalis muscle is attached to the floor and inferior temporal line . CONTENTS: Temporalis muscle Middle temporal artery Zygomaticotemporal nerve and artery Deep temporal nerves Deep temporal artery ( br.of maxillary artery) https://youtu.be/StcArj0N5KQ

4. INFRATEMPORAL FOSSA IT IS A IRREGULAR SPACE BELOW ZYGOMATIC ARCH BOUNDARIES: Ant : posterior surface of body of maxilla Roof : infratemporal surface of greater wing of sphenoid. Medial: lateral pterygoid plate and pyramidal process. Lateral : ramus of mandible. CONTENTS: Lateral pterygoid muscle Medial pterygoid Mandibular nerve with its branches Maxillary nerve with post superior alveolar nerve Chorda tympani, br.of facial nerve(7) 1 st and 2 nd parts of maxillary artery with branches.

5. MASSETER (quadrilateral) ORIGIN: Zygomatic arch and zygomatic process of maxilla INSERTION : Ramus of mandible NERVE SUPPLY: Massater nerve br.of mandibular nerve . ACTIONS: Elevation and protrudes TEMPORALIS(fan shaped) ORIGIN: Temporal fossa and fascia. INSERTION: Coronoid process and ant. Border of ramus of mandible. NERVESUPPLY: Temporal br of mandibular nerve. ACTIONS: Elevation and protrudes.

6. LATERAL PTERYGOID ORIGIN: Greater wing of sphenoid bone INSERTION: Pterygoid fovea and articular disc and capsule of TMJ. NERVESUPPLY: Mandibular nerve. ACTION: Depresses and protrudes. MEDIAL PTERYGOID ORIGIN: Tuberosity of maxilla and lateral pterygoid plate. INSERTION: Angle adjoining ramus of mandible and behind the mandibular foramen and mylohyoid groove. NERVESUPPLY: Mandibular nerve ACTION: Elevates and protrudes. CLINICAL ANATOMY:- Temporalis and masseter are palpated by requested person to clench the teeth. medial and lateral pterygoid muscles can be tested by requesting person to move lower jaw from one side to other side

7. MAXILLARY ARTERY IT IS THE LARGEST TERMINAL BRANCH OF ECA. >>>IT DISTRIBUTES AND SUPPLIES TO The external and middle ears and auditory tube . The Dura mater . Upper and lower jaws with their teeth . Muscles of temporal and infratemporal regions . https://youtu.be/vn310eLU8ao Nose and paranasal air sinuses . Palate . Pharynx . COURSE AND RELATIONS :- 1 st part (mandibular part) b/w neck of mandible and sphenomandibular ligament 2 nd part (pterygoid) runs forwards and upwards superficial to lower head of lateral pterygoid . 3 rd part (pterygopalatine) passes b/w two heads of lateral pterygoid and the pterygomaxillary fissure . https://youtu.be/kA-eclsRK_w

8. 1 ST PART ARTERY DEEP AURICULAR ANTERIOR TYMPANIC MIDDLE MENINGIAL ACCESSORY MENINGIAL INFERIOR ALVEOLAR DISTRBUTION External acoustic meatus and outer surface of tympanic membrane Inner surface of tympanic membrane . Middle ear and tensor tympani , supplies more of bones and less of meninges. Extracranial to pterygoids . Lower 8 th teeth and mylohyoid muscles .

9. 2 ND PART ARTERY MASSETRIC DEEP TEMPORAL PTERYGOID BUCCAL DISTRIBUTION Masseter Temporalis (2 br.) Lateral and medial pterygoid Skin of the cheek

10. ARTERY POSTERIOR SUPERIOR ALVEOLAR INFRAORBITAL GREATER PALATINE PHARYNGEAL ARTERY OF PTERYGOID CANAL SPHENOPALATINE DISTRIBUTION Upper molar and premolar teeth and maxillary sinus . Lower orbital muscles , lacrimal sac , maxillary sinus ,upper incisor and canine teeth . Soft palate , tonsil , and mucosa of upper gums . Roof of nose and pharynx , auditory tube , sphenoidal sinus . Auditory tube , upper pharynx and middle ear . Lateral and medial walls of nose and various air sinuses. 3 rd PART

11. TEMPOROMANDIBULAR JOINT Synovial type of joint. ARTICULAR SURFACES:- upper articular surface is formed by………….. Articular tubercle Ant part of mandibular fossa. Post non articular part is formed by tympanic plate. Inferior articular surface is formed by ……… Head of mandible. Articular surfaces are covered with fibro cartilage. Fibrous capsule is attached above to the articular tubercle .the synovial membrane lines the fibrous capsule ant neck of mandible . Lateral temporomandibular ligament strengthens the lateral part of capsular ligament . ARTICULAR CAPSULE: -loose and is attached in front of root of zygomatic process . It inserts to the neck of mandible blw the head . https://youtu.be/0BKU04QLzV0

12. LIGAMENTS:- Stylomandibular :- styloid process to angle of mandible . Sphenomandibular :- sphenoid bone to lingula of mandible . Temporomandibular :- root of zygomatic arch to neck of mandible ARTICULAR DISC:--- It is the oval fibrous plate that divides joint into upper and lower compartments. Upper compartment permits gliding movements and lower compartments permits rotatory as well as gliding. Disc has concavo-convex superior surface It acts as cushion and helps in shock absorption The proprioceptive fibres present in the disc helps in regulate movements of joint. RELATIONS OF TMJ :- LATERAL:- Skin and fascia Parotid gland Temporal branches of facial nerve MEDIAL:- Tympanic plate separates joint from ICA. Spine of sphenoid. Auriculotemporal and chorda tympani nerves. Middle meningeal artery

13. ANTERIOR:- Lateral pterygoid Massetric nerve and artery POSTERIOR:- Parotid gland separates the joint from external auditory meatus. Superficial temporal vessels Auriculotemporal nerve SUPERIOR:- Middle cranial fossa Middle meningeal vessels INFERIOR:- Maxillary artery and vein BLOOD SUPPLY AND NERVE SUPPLY:- br of superficial temporal amd maxillary arteries…..auriculotemporal and massetric nr. MOVEMENTS:- Depression (opens mouth0 Elevation (closed mouth) Protrusion(protraction of chin) Retrusion (retraction of chin) Lateral or side to side movements during chewing..

14. MANDIBULAR NERVE It is the largest mixed branch of trigeminal nerve(5). Largest nerve of 1 st brachial arch supplies all structures of that arch. Otic and submandibular ganglia associated with this nerve COURSE AND RELATIONS:- *** MANDIBULAR NERVE BEGINS IN MIDDLE CRANIAL FOSSA THROUGH A LARGE SENSORY ROOT AND SMALL MOTOR ROOT.***** Sensory root arises from lateral part of trigeminal ganglion , and leaves the cranial cavity through foramen ovale . Motor root lies deep to tgg and sensory part.it passes through foramen ovale to join sensory root just below foramen. Main trunk lies in tensor veli palatini and deep to lateral pterygoid. BRANCHES:- From the main trunk…….. Meningeal branch Nerve to medial pterygoid From the anterior trunk…….. Sensory branch –buccal nerve Motor branches – masseteric ,deep temporal , nerve to lateral pterygoid . From posterior trunk……. Auriculotemporal Lingual Inf.alveolar nerves.

15. BRANCHES MENINGIAL BRANCH:- Meningeal branch enters the skull through foramen spinosum eith the middle meningeal artery &supplies the dura mater of middle cranial fossa . NERVE TO MEDIAL PTERYGOID: arises close to Otic ganglion and supplies medial pterygoid . BUCCAL NERVE:- buccal nerve is the only sensory nerve of ant division of mandibular nerve. It passes b/w two heads of lateral pterygoid , runs frwrd and bckwrd and supplies to skin of cheek and mucous membrane related to buccinator . It also supplies the labial aspects of gums of molar and premolar teeth . MASSETRIC NERVE:- emerges at the upper border of lateral pterygoid just in-front of TMJ .it also supplies the TMJ . DEEP TEMPORAL:- two branches they passs b/w skull and lateral pterygoid , and enter the deep structures of temporalis. NERVE TO LATERAL PTERYGOID:- enters the deep structures of muscle . AURICULO TEMPORAL :- arises by 2 root run backwards and encircle middle meningeal artery and unite to form single trunk . The nerve continues backwards between the neck of the mandible and the sphenomandibular ligament, above the maxillary artery. The auricular part of the nerve supplies the skin of the tragus; and the upper parts of the pinna, the external acoustic meatus and the tympanic membrane . The temporal part supplies the skin of the temple . In addition, the auriculotemporal nerve also supplies the parotid gland (secretomotor and also sensory , and the temporomandibular joint . LINGUAL NERVE:- two terminal branches of post division of mandibular nerve . It is sensory to the anterior two-thirds of the tongue and to the floor of the mouth . chorda tympani (branch of facial nerve) which is secretomotor to the submandibular and sublingual salivary glands and gustatory to the anterior two-thirds of the tongue , are also distributed through the lingual nerve . Course : Lingual nerve begins 1 cm below the skull . Joined by chorda tympani that lies in contact with 3 rd molar tooth . it lies on surface of hyoglossus and genioglossus to reach the tongue

16. Relations : It runs first between the tensor veli palatini and the lateral pterygoid, and then between the lateral and medial pterygoids. INFERIOR ALVEOLAR NERVE:- larger terminal branch of the posterior division of the mandibular nerve . It enters the mandibular foramen and runs in the mandibular canal. It is accompanied by the inferior alveolar artery . Branches :- The mylohyoid branch contains all the motor fibers of the posterior division . Runs in the mylohyoid groove, and supplies the mylohyoid muscle and the anterior belly of the digastric . Inferior alveolar nerve gives branches that supply the lower teeth and gums . The mental nerve emerges at the mental foramen and supplies the skin of the chin, and the skin and mucous membrane of the lower lip . Its incisive branch supplies the labial aspect of gums of canine and incisor teeth.

17. OTIC GANGLION It is a peripheral parasympathetic ganglion which relays secretomotor fibers to the parotid gland. Related to the mandibular nerve, but functionally, it is a part of the glossopharyngeal nerve . Size and Situation :- It is 2 to 3 mm in size, and is situated in the infratemporal fossa, just below the foramen ovale . It lies medial to the mandibular nerve, and lateral to the tensor veli palatini. Connections and Branches :- The secretomotor motor or parasympathetic root is formed by the lesser petrosal nerve. The sympathetic root is derived from the plexus on the middle meningeal artery. It contains postganglionic fibres arising in the superior cervical ganglion. The sensory root comes from the auriculotemporal nerve and is sensory to the parotid gland . The nerve to medial pterygoid gives a motor root to the ganglion which passes through it without relay and supplies medially placed tensor veli palatini and laterally placed tensor tympani muscles. The chorda tympani nerve is connected to the otic ganglion and also to the nerve of the pterygoid canal . These connections provide an alternative pathway of taste from the anterior two thirds of the tongue .