Podcast
Questions and Answers
What is the primary function of the infrahyoid muscles during swallowing?
What is the primary function of the infrahyoid muscles during swallowing?
Which muscle can depress the mandible when acting in conjunction with infrahyoid and lateral pterygoid muscles?
Which muscle can depress the mandible when acting in conjunction with infrahyoid and lateral pterygoid muscles?
What is the primary function of the buccinators during swallowing?
What is the primary function of the buccinators during swallowing?
What is the primary function of the salivary glands during swallowing?
What is the primary function of the salivary glands during swallowing?
Signup and view all the answers
Which of the following muscles is NOT primarily involved in swallowing?
Which of the following muscles is NOT primarily involved in swallowing?
Signup and view all the answers
What type of movement does the mandible make when the lateral pterygoid and hyoid muscles contract together?
What type of movement does the mandible make when the lateral pterygoid and hyoid muscles contract together?
Signup and view all the answers
What is the primary function of the masseter muscle in regards to the mandible?
What is the primary function of the masseter muscle in regards to the mandible?
Signup and view all the answers
What is the origin of the deep fibres of the masseter muscle?
What is the origin of the deep fibres of the masseter muscle?
Signup and view all the answers
What is the primary action of the temporalis muscle on the mandible?
What is the primary action of the temporalis muscle on the mandible?
Signup and view all the answers
Which of the following structures is NOT an origin of the temporalis muscle?
Which of the following structures is NOT an origin of the temporalis muscle?
Signup and view all the answers
What is the insertion of the masseter muscle?
What is the insertion of the masseter muscle?
Signup and view all the answers
What movement of the mandible is facilitated by the superficial fibres of the masseter muscle?
What movement of the mandible is facilitated by the superficial fibres of the masseter muscle?
Signup and view all the answers
What muscle is responsible for opening the oropharyngeal isthmus during bolus formation?
What muscle is responsible for opening the oropharyngeal isthmus during bolus formation?
Signup and view all the answers
Which muscles contract to close the nasopharynx from the oropharynx during swallowing?
Which muscles contract to close the nasopharynx from the oropharynx during swallowing?
Signup and view all the answers
What is the purpose of the epiglottis during swallowing?
What is the purpose of the epiglottis during swallowing?
Signup and view all the answers
Which muscles contract to raise and bring the larynx forward during swallowing?
Which muscles contract to raise and bring the larynx forward during swallowing?
Signup and view all the answers
What is the function of the middle and inferior constrictors during swallowing?
What is the function of the middle and inferior constrictors during swallowing?
Signup and view all the answers
What is the duration of the swallowing process from the oropharynx to the stomach?
What is the duration of the swallowing process from the oropharynx to the stomach?
Signup and view all the answers
What type of action is facilitated when the suprahyoid muscles contract bilaterally?
What type of action is facilitated when the suprahyoid muscles contract bilaterally?
Signup and view all the answers
What is the primary function of the infrahyoid muscles during swallowing?
What is the primary function of the infrahyoid muscles during swallowing?
Signup and view all the answers
Which muscles are responsible for breaking down food mechanically during swallowing?
Which muscles are responsible for breaking down food mechanically during swallowing?
Signup and view all the answers
What is the function of ptyalin in saliva during swallowing?
What is the function of ptyalin in saliva during swallowing?
Signup and view all the answers
What is the purpose of the lips during swallowing?
What is the purpose of the lips during swallowing?
Signup and view all the answers
What is the action of the medial pterygoid muscle when it contracts together with the masseter muscle?
What is the action of the medial pterygoid muscle when it contracts together with the masseter muscle?
Signup and view all the answers
Which muscle is NOT involved in depressing the mandible during swallowing?
Which muscle is NOT involved in depressing the mandible during swallowing?
Signup and view all the answers
What is the action of the lateral pterygoid muscle when it contracts together with its counterpart on the opposite side?
What is the action of the lateral pterygoid muscle when it contracts together with its counterpart on the opposite side?
Signup and view all the answers
What is the shape of the lateral pterygoid muscle?
What is the shape of the lateral pterygoid muscle?
Signup and view all the answers
What is the action of the medial pterygoid muscle on the mandible when it contracts unilaterally?
What is the action of the medial pterygoid muscle on the mandible when it contracts unilaterally?
Signup and view all the answers
What is the relationship between the medial pterygoid muscle and the masseter muscle?
What is the relationship between the medial pterygoid muscle and the masseter muscle?
Signup and view all the answers
Which type of fibres are involved in retrusion of the mandible?
Which type of fibres are involved in retrusion of the mandible?
Signup and view all the answers
What is the primary action of the palatoglossus muscles during bolus formation?
What is the primary action of the palatoglossus muscles during bolus formation?
Signup and view all the answers
What is the name of the joint that allows for the movement of the lower jaw during mastication?
What is the name of the joint that allows for the movement of the lower jaw during mastication?
Signup and view all the answers
What is the result of the contraction of the superior constrictor muscles during swallowing?
What is the result of the contraction of the superior constrictor muscles during swallowing?
Signup and view all the answers
What is the function of the aryepiglottic and transverse arytenoid muscles during swallowing?
What is the function of the aryepiglottic and transverse arytenoid muscles during swallowing?
Signup and view all the answers
What is the function of the articular disc in the temporomandibular joint?
What is the function of the articular disc in the temporomandibular joint?
Signup and view all the answers
Which of the following muscles is NOT one of the four major masticatory muscles?
Which of the following muscles is NOT one of the four major masticatory muscles?
Signup and view all the answers
What is the result of the contraction of the levator muscles during swallowing?
What is the result of the contraction of the levator muscles during swallowing?
Signup and view all the answers
What is the name of the artery that supplies blood to the muscles of mastication?
What is the name of the artery that supplies blood to the muscles of mastication?
Signup and view all the answers
What is the action of the tongue during bolus formation?
What is the action of the tongue during bolus formation?
Signup and view all the answers
What is the result of the contraction of the middle and inferior constrictors during swallowing?
What is the result of the contraction of the middle and inferior constrictors during swallowing?
Signup and view all the answers
What is the name of the plexus of veins that drains the muscles of mastication?
What is the name of the plexus of veins that drains the muscles of mastication?
Signup and view all the answers
What is the name of the fossa that allows for the passage of the temporalis and pterygoid muscles?
What is the name of the fossa that allows for the passage of the temporalis and pterygoid muscles?
Signup and view all the answers
What is the nerve responsible for the innervation of the musculature and mucosa of the oral cavity?
What is the nerve responsible for the innervation of the musculature and mucosa of the oral cavity?
Signup and view all the answers
What is the type of movement that occurs in the upper compartment of the temporomandibular joint?
What is the type of movement that occurs in the upper compartment of the temporomandibular joint?
Signup and view all the answers
What is the name of the artery that is subdivided into mandibular, pterygoid, and pterygopalatine parts?
What is the name of the artery that is subdivided into mandibular, pterygoid, and pterygopalatine parts?
Signup and view all the answers
What is the name of the vein that drains into the internal jugular vein?
What is the name of the vein that drains into the internal jugular vein?
Signup and view all the answers
What happens to the hyoid bone and larynx after the bolus passes through?
What happens to the hyoid bone and larynx after the bolus passes through?
Signup and view all the answers
What is the role of the intrinsic and extrinsic muscles of the larynx during swallowing?
What is the role of the intrinsic and extrinsic muscles of the larynx during swallowing?
Signup and view all the answers
What happens to the upper oesophageal sphincter during the upper oesophageal phase?
What happens to the upper oesophageal sphincter during the upper oesophageal phase?
Signup and view all the answers
What type of movement is swallowing initially, before it becomes involuntary?
What type of movement is swallowing initially, before it becomes involuntary?
Signup and view all the answers
During the pharyngeal phase, what happens to the larynx?
During the pharyngeal phase, what happens to the larynx?
Signup and view all the answers
What happens to the soft palate during the buccal phase?
What happens to the soft palate during the buccal phase?
Signup and view all the answers
What is the primary action of the levator muscles during swallowing?
What is the primary action of the levator muscles during swallowing?
Signup and view all the answers
What is the function of the palatoglossus muscles during bolus formation?
What is the function of the palatoglossus muscles during bolus formation?
Signup and view all the answers
What is the result of the contraction of the superior constrictor muscles during swallowing?
What is the result of the contraction of the superior constrictor muscles during swallowing?
Signup and view all the answers
What is the role of the epiglottis during swallowing?
What is the role of the epiglottis during swallowing?
Signup and view all the answers
What is the function of the aryepiglottic and transverse arytenoid muscles during swallowing?
What is the function of the aryepiglottic and transverse arytenoid muscles during swallowing?
Signup and view all the answers
What is the duration of the swallowing process from the oropharynx to the stomach?
What is the duration of the swallowing process from the oropharynx to the stomach?
Signup and view all the answers
What is the shape of the masseter muscle?
What is the shape of the masseter muscle?
Signup and view all the answers
What is the origin of the deep fibres of the temporalis muscle?
What is the origin of the deep fibres of the temporalis muscle?
Signup and view all the answers
What is the action of the superficial fibres of the masseter muscle?
What is the action of the superficial fibres of the masseter muscle?
Signup and view all the answers
What is the insertion of the temporalis muscle?
What is the insertion of the temporalis muscle?
Signup and view all the answers
What is the action of the masseter muscle in regards to the mandible?
What is the action of the masseter muscle in regards to the mandible?
Signup and view all the answers
What is the action of the temporalis muscle on the mandible?
What is the action of the temporalis muscle on the mandible?
Signup and view all the answers
What is the primary function of the suprahyoid muscles during swallowing when acting in conjunction with the infrahyoid muscles?
What is the primary function of the suprahyoid muscles during swallowing when acting in conjunction with the infrahyoid muscles?
Signup and view all the answers
Which muscle is involved in breaking down food mechanically during swallowing?
Which muscle is involved in breaking down food mechanically during swallowing?
Signup and view all the answers
What occurs to the hyoid bone and larynx during swallowing?
What occurs to the hyoid bone and larynx during swallowing?
Signup and view all the answers
What is the primary function of ptyalin in saliva during swallowing?
What is the primary function of ptyalin in saliva during swallowing?
Signup and view all the answers
What is the role of the lips during swallowing?
What is the role of the lips during swallowing?
Signup and view all the answers
What type of movement does the mandible make when the contralateral excursion occurs?
What type of movement does the mandible make when the contralateral excursion occurs?
Signup and view all the answers
What is the primary function of the articular disc in the temporomandibular joint?
What is the primary function of the articular disc in the temporomandibular joint?
Signup and view all the answers
Which of the following muscles is NOT responsible for elevating the mandible?
Which of the following muscles is NOT responsible for elevating the mandible?
Signup and view all the answers
What is the primary function of the infratemporal fossa?
What is the primary function of the infratemporal fossa?
Signup and view all the answers
What is the primary function of the maxillary artery?
What is the primary function of the maxillary artery?
Signup and view all the answers
What is the primary function of the pterygoid venous plexus?
What is the primary function of the pterygoid venous plexus?
Signup and view all the answers
What is the primary function of the mandibular nerve?
What is the primary function of the mandibular nerve?
Signup and view all the answers
What type of movement occurs in the lower compartment of the temporomandibular joint?
What type of movement occurs in the lower compartment of the temporomandibular joint?
Signup and view all the answers
What is the primary function of the temporalis muscle?
What is the primary function of the temporalis muscle?
Signup and view all the answers
What is the primary function of the medial pterygoid muscle?
What is the primary function of the medial pterygoid muscle?
Signup and view all the answers
What is the primary function of the lateral pterygoid muscle?
What is the primary function of the lateral pterygoid muscle?
Signup and view all the answers
What is the primary function of the larynx during swallowing?
What is the primary function of the larynx during swallowing?
Signup and view all the answers
What happens to the soft palate during the buccal phase of swallowing?
What happens to the soft palate during the buccal phase of swallowing?
Signup and view all the answers
What is the primary function of the upper oesophageal phase during swallowing?
What is the primary function of the upper oesophageal phase during swallowing?
Signup and view all the answers
What is the role of peristalsis during the oesophageal phase of swallowing?
What is the role of peristalsis during the oesophageal phase of swallowing?
Signup and view all the answers
What happens to the hyoid bone and larynx after the bolus passes through?
What happens to the hyoid bone and larynx after the bolus passes through?
Signup and view all the answers
What is the initial type of movement during swallowing?
What is the initial type of movement during swallowing?
Signup and view all the answers
What is the function of the articular disc in the temporomandibular joint?
What is the function of the articular disc in the temporomandibular joint?
Signup and view all the answers
What is the name of the fossa that allows for the passage of the temporalis and pterygoid muscles?
What is the name of the fossa that allows for the passage of the temporalis and pterygoid muscles?
Signup and view all the answers
What is the name of the nerve responsible for the innervation of the musculature and mucosa of the oral cavity?
What is the name of the nerve responsible for the innervation of the musculature and mucosa of the oral cavity?
Signup and view all the answers
What type of movement occurs in the upper compartment of the temporomandibular joint?
What type of movement occurs in the upper compartment of the temporomandibular joint?
Signup and view all the answers
What is the name of the plexus of veins that drains the muscles of mastication?
What is the name of the plexus of veins that drains the muscles of mastication?
Signup and view all the answers
What is the name of the artery that supplies blood to the muscles of mastication?
What is the name of the artery that supplies blood to the muscles of mastication?
Signup and view all the answers
Which muscle plays a crucial role in protrusion of the mandible?
Which muscle plays a crucial role in protrusion of the mandible?
Signup and view all the answers
What is the primary action of the suprahyoid muscles during swallowing?
What is the primary action of the suprahyoid muscles during swallowing?
Signup and view all the answers
What is the role of the maxillary artery in relation to the muscles of mastication?
What is the role of the maxillary artery in relation to the muscles of mastication?
Signup and view all the answers
During which stage of swallowing does the bolus pass through the pharynx?
During which stage of swallowing does the bolus pass through the pharynx?
Signup and view all the answers
What is the primary action of the temporalis muscle on the mandible?
What is the primary action of the temporalis muscle on the mandible?
Signup and view all the answers
What is the primary function of the buccinator muscle in relation to the mandible?
What is the primary function of the buccinator muscle in relation to the mandible?
Signup and view all the answers
What is the primary function of the infratemporal fossa?
What is the primary function of the infratemporal fossa?
Signup and view all the answers
Which type of movement occurs in the lower compartment of the temporomandibular joint?
Which type of movement occurs in the lower compartment of the temporomandibular joint?
Signup and view all the answers
What is the primary function of the pterygoid plexus of veins?
What is the primary function of the pterygoid plexus of veins?
Signup and view all the answers
Which nerve is responsible for the innervation of the muscles of mastication?
Which nerve is responsible for the innervation of the muscles of mastication?
Signup and view all the answers
What is the primary function of the articular disc in the temporomandibular joint?
What is the primary function of the articular disc in the temporomandibular joint?
Signup and view all the answers
What is the primary artery that supplies blood to the muscles of mastication?
What is the primary artery that supplies blood to the muscles of mastication?
Signup and view all the answers
What is the primary function of the Maxillary artery?
What is the primary function of the Maxillary artery?
Signup and view all the answers
What is the action of the Lateral pterygoid muscle on the mandible when it contracts unilaterally?
What is the action of the Lateral pterygoid muscle on the mandible when it contracts unilaterally?
Signup and view all the answers
What is the primary action of the Suprahyoid muscles during swallowing?
What is the primary action of the Suprahyoid muscles during swallowing?
Signup and view all the answers
What is the sequence of the three main stages of swallowing?
What is the sequence of the three main stages of swallowing?
Signup and view all the answers
What is the action of the Medial pterygoid muscle on the mandible when it contracts together with the Masseter muscle?
What is the action of the Medial pterygoid muscle on the mandible when it contracts together with the Masseter muscle?
Signup and view all the answers
What is the result of the contraction of the Inferior constrictor muscles during swallowing?
What is the result of the contraction of the Inferior constrictor muscles during swallowing?
Signup and view all the answers
Study Notes
Anatomy of the Head and Neck
- Mastication, TMJ, and Swallowing
- Lecture outcomes:
- Describe the functional anatomy of the TMJ
- List the muscles of mastication, attachments, actions, blood, and innervation
- Describe the infratemporal fossa and its contents
- Lecture outcomes:
Mastication
- Process of mastication involves movement of the lower jaw
- Movement possible due to the synovial joint between the mandible and temporal bone
- Movement at the TMJ allows:
- Incisors to function in biting
- Molars to grind food
- Tongue to place/keep food between molars
Temporomandibular Joint (TMJ)
- Articular disc divides the joint cavity into two
- Allows for six types of movement:
- Lateral deviation
- Protrusion
- Retrusion
- Elevation
- Depression
- Movement types:
- Gliding (deviation) in the upper compartment
- Hinge (rotation) in the lower compartment
- Combination of gliding and hinge movements enables six basic movements of the mandible
Infratemporal Fossa
- Space posterior to the maxilla and deep to the zygomatic arch and ramus of the mandible
- Allows passage of:
- Temporalis and pterygoid muscles
- Maxillary artery and pterygoid venous plexus
Neurovasculature of Muscles of Mastication
- Blood supply from the maxillary artery, a terminal branch of the external carotid
- Equivalent drainage is the pterygoid venous plexus
- Innervation via the anterior trunk of the mandibular nerve
- Also responsible for innervation of the musculature and mucosa of the oral cavity and cheeks
Masseter Muscle
- Quadrilateral in shape
- Originates from the zygomatic bone/arch and inserts on the anterior border and angle of the ramus of the mandible
- Superficial fibers run obliquely, while deep fibers run vertically
- Actions:
- Elevation: uses both masseter muscles, enabling teeth to be clenched
- Retrusion: uses superficial fibers, retruding a protruded mandible
- Ipsilateral excursion: a single masseter can move the mandible to the same side
Temporalis Muscle
- Fan-shaped muscle
- Originates from the side of the skull and inserts at the coronoid process of the mandible
- Arises from two heads: temporal bone and temporal fascia
- Actions:
- Resting tonus: maintains normal mandibular rest position when upright
- Elevation: enables the teeth to be clenched
Hyoid Muscles
- Supra- and infrahyoid muscles primarily involved in swallowing
- Contract bilaterally
- Actions:
- Infrahyoid muscles: depress the hyoid bone and larynx during swallowing
- Suprahyoid muscles: raise the hyoid bone and larynx when the mandible is stabilized, but can also depress the mandible when acting with infrahyoid and lateral pterygoid muscles
- Muscles involved:
- Geniohyoid
- Stylohyoid
- Thyrohyoid
- Sternothyroid
- Sternohyoid
- Omohyoid
- Digastric
- Mylohyoid
Bolus Formation and Swallowing
-
Incisors and canines take in small portions of solid food
-
Food is moistened by saliva containing ptyalin, which breaks down carbohydrates
-
Mechanical action by molars and premolars, assisted by the tongue, breaks down food
-
Cheeks prevent food from entering the vestibule
-
Lips reduce the likelihood of food falling out of the mouth
-
Tongue gathers food into a bolus and pushes it towards the oral pharynx
-
Palatoglossus muscles relax to open the oropharyngeal isthmus
-
Swallowing involves:
- Pharyngeal phase: bolus comes into contact with the pharyngeal wall, and muscles propel it towards the esophagus
- Oesophageal phase: bolus passes through the upper and lower oesophagus, driven by peristalsis### Mastication and TMJ
-
The TMJ cavity is divided by the articular disc and allows for 6 types of movements: lateral deviation, protusion, retrusion, elevation, and depression.
-
Gliding movement occurs in the upper compartment between the moving disc and stationary fossa.
-
Hinge movement occurs in the lower compartment between the moving condyle and stationary disc.
-
The infratemporal fossa is a space found posterior to the maxilla and deep to the zygomatic arch and ramus of mandible, allowing the passage of muscles of mastication (temporalis and pterygoid), the maxillary artery, and the pterygoid plexus of veins.
Muscles of Mastication
- Masseter muscle: originates from the zygomatic arch/bone, inserts into the anterior border of the angle and ramus of mandible, and performs elevation, retrusion, and ipsilateral excursion.
- Temporalis muscle: originates from the side of the skull (mostly temporal bone), inserts into the coronoid process of mandible, and performs elevation, retrusion, and ipsilateral excursion, as well as tonus.
- Medial pterygoid muscle: originates from the medial surface of the lateral pterygoid plate, inserts into the ramus and angle of the mandible, and performs elevation, protrusion, and contralateral excursion.
- Lateral pterygoid muscle: originates from the lateral pterygoid plate and sphenoid bones, inserts into the condyle of the mandible, and performs depression, protrusion, and contralateral excursion.
Blood Supply and Innervation
- The maxillary artery provides blood to the muscles of mastication and the buccinator (cheek) muscle.
- The pterygoid plexus of veins drains into the maxillary vein and anastomoses with the facial vein.
- The mandibular nerve supplies muscles of mastication, as well as the muscles and mucosa of the floor and the buccinator muscle.
Swallowing
-
Swallowing involves moving the pharynx (and larynx) upwards, opening its lumen, and moving the hyoid bone.
-
Raising the pharynx is achieved by contracting the suprahyoid muscles while stabilizing the mandible.
-
Depressing the pharynx is achieved by contracting the infrahyoid and lateral pterygoid muscles.
-
The timeline of swallowing consists of 3 main stages: buccal, pharyngeal, and oesophageal.
-
Bolus formation: the tongue gathers the food into a bolus and pushes it towards the oral pharynx by raising against the hard palate.
-
The palatoglossus muscles relax to open the oropharyngeal isthmus.
-
As the bolus reaches the oropharynx, the soft palate is tensed and raised by the levator muscles.
-
The superior constrictor contracts to close the nasopharynx from the oropharynx, and the suprahyoid muscles contract to raise and bring the larynx forward.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
This quiz covers the anatomy of hyoid muscles, including their functions in swallowing and movement of the mandible and hyoid bone. Learn about the suprahyoid and infrahyoid muscles and their roles in depression and elevation.