Temporomandibular joint

The temporalis masseter and medial and lateral pterygoid muscles are the muscles of mastication that attach to the mandible. The buccinator muscle, which controls the contents of the mouth during mastication, is innervated by the seventh cranial nerve and constitutes the chief muscle of facial expression. The lateral pterygoid muscles, acting bilaterally protract the jaw and, acting unilaterally rotate the jaw during chewing. Because the fibers of the superior head of the lateral pterygoid muscle insert onto the anterior aspect of the articular disk of the temporomandibular joint as well as onto the head of the mandible, spasm of this muscle, such as in a yawn, can result in dislocation of the mandible by pulling the disk anterior to the articular tubercle Reduction is accomplished by pushing the mandible downward and back, so that the head of the mandible reenters the mandibular fossa. The temporalis, medial pterygoid and masseter muscles primarily elevate the jaw in molar occlusion

Temporomandibular joint REF: Dhingra’s ENT P-400, Cawson’s essentials of oral pathology and oral medicine By R. A. Cawson, E. W. Odell page. 199

“Costen’s syndrome is abnormality of temporomandibular joint due to defective bite. It is characterized by otalgia, feeling of blocked ear, tinnitus and sometimes vertigo. Pain also radiates to frontal, parietal and occipital region”

“Costen’s syndrome is an antiquated term applies to headache, ear symptoms (otalgia, tinnitus) and burning pain in tongue and throat and was ascribed to over closure causing excessive backward movement of head of condyle”

Base of skull fracture REF: Miller 6^th ed p. 1628-1645

Contraindications for nasal intubation:

• Base of skull fracture
• CSF rhinorrhoea
• Adenoids
• Nasal polyps
• Bleeding disorder
• Previous nasal surgery

Indications for blind nasal intubation

• Impossible laryngoscopy
• TM joint problems
• Trismus due to any cause
• Neck contracture

Condyloid joint

Condylar joint

Blind intubation techniques are those methods of airway management that are done without visualization of the larynx or glottis. 

Blind nasal intubation is contra-indicated in the presence of a base-of-skull fracture,

e.g., with ‘raccoon eyes’ or with CSF dripping from the nose, as the endotracheal tube can enter the brain.

Indications for blind nasal intubation include impossible laryngoscopy, TM joint problems or trismus due to any cause.

• Temporalis muscle: The temporalis muscle elevates the mandible.
• Masseter muscle: It elevates the mandible. It works functionally with the temporalis and pterygoid muscles to move the mandible at the TMJ, it is a muscle of mastication.
• Lateral pterygoid muscle: Contraction causes the mandibular condyle and the articular disc to move anteriorly, resulting in both protraction and depression of the mandible. It works synergistically with the medial pterygoid muscle to move the mandible from side to side.
• Medial pterygoid muscle: It elevates the mandible and moves it from side to side.

The articulations between the temporal bone (mandibular fossa) and the mandibular condyle form a synovial joint, known as the temporomandibular joint (TMJ).A unique feature of the TMJ is the fibrocartilaginous articular disc, located within the joint capsule between the mandibular fossa and condyle.

 Vestibule of nose is supplied by maxillary nerve which does not supply the ear.

Ans. Transverse, fracture of Atlas