This superior lateral pterygoid originates on the infratemporal surface of the greater wing of the sphenoid and it inserts superiorly on the condylar process of the mandible. Link to this page: mastication During chewing, the type of food cut anterior, lateral, hand or tear , chewing type unilateral or bilateral, simultaneous or alternating and lip position during mastication were analyzed, as well as the number of masticatory cycles of each of the four portions, considering the average of this variable. The three musculi masticatorii include the masseter, medial pterygoid, and the temporalis. It overlies the lateral surface of the mandibular ramus. The two pterygoid muscles lateral and medial cannot be seen easily look at the exterior surface of the skull - they lie beneath the mandible and insert onto it's medial inside surface.
The Temporalis muscle on the other hand, being larger in size and also having more surface area of attachment is only used to elevate or lift the mandible and does not put any force for chewing. This is the posterior process on the mandible. The origin of the anterior fibres descend towards the lower border of the mandible. If you have any doubts feel free to contact me or comment in the post, thanks for visiting. Muscle Location Function Masseter Muscle It consists of two overlapping muscles. The former starts from the pterygoid process, and gets inserted into the mandible. The three muscles of mastication help you close your mouth; the last one helps open the mouth.
Four movements of the mandible. The fibers of the lateral pterygoid muscle run backward and a little laterally. The main insertion of the lateral pterygoid is into this hollow on the front of the condylar process. Origin of Medial Pterygoid The medial pterygoid muscles originate from the lateral pterygoid plate of sphenoid bone with few of its fibers arising from the maxillary tuberosity. Activities The temporalis muscle elevates the mandible and so shuts the mouth and approximates the.
It receives nerve supply from the inferior alveolar branch of mandibular nerve that starts before entering the inferior alveolar canal. The deep portion of the muscle is partly concealed, in front, by the superficial portion; behind, it is covered by the parotid gland. Mastication is the first step of the digestive process. The lateral pterygoid has two heads. The latter starts from the sphenoid bone, and gets inserted into the articular disc. In cases where a human or animal cannot chew for themselves, a process called premastication may take place.
The move the to bring the teeth into intermittent contact, repeatedly and opening. The lateral pterygoid also protacts the jaw. The field of insertion is approximately triangular. Looking at the origin and the insertion of the temporalis muscle, you can see that it elevates it and it can also retract it looking at the direction of the fibers. The medial pterygoid muscle arises from both the pterygoid plates: the medial aspect of the lateral one, and the lateral aspect of the medial one, also from this corner of the maxilla, the tuber. Both the heads end into the ramus and the body of the mandible. The pterygoid muscles can be confusing The pterygoid muscles are so-named, because they originate on the ptergoid process, which is a downward pointing process that extends from the sphenoid bone.
These muscles are superficial, intermediate, and deep. These muscles are responsible for chewing. Activities The elevates the mandible to shut the mouth. Insertion The fibres converge and descend to create a tendon, which goes through the gap between the zygomatic arch and the side of the. These muscles get their blood supply from the pterygoid branch of maxillary artery. Nerve Supply The masseter is supplied by a masseteric nerve, a branch from anterior section of the mandibular nerve.
The temporalis muscle receives blood supply from anterior, posterior, and superficial temporal arteries, and receive nerve supply from temporal nerves. The anterior fibres are oriented vertically, the posteriormost fibres are disposed nearly horizontally and interceding intermediate fibres are positioned obliquely. They eventually became some of the most successful animals on the planet until the wiped them out. These two muscles share the same features with two origin point and as a result both have two heads. December 2013 Chewing is largely an adaptation for.
Closing is produced by three large muscles on each side, the medial pterygoid, the temporalis, and the masseter. Geniohyoid muscle receives its blood supply from lingual artery, and nerve supply from hypolossal nerve. The Masticatory Cycle The masticatory cycle is the pathway that the mandible takes while chewing food. If I just bring back the muscles that I got rid of, this muscle here is the masseter. Painful teeth may cause slow, intermittent or one-sided eating. If I just remove the masseter and remove the mandible temporarily, you can see the pterygoid process sticking down. There are three phases in the physiology of mastication: the incision of food, the mastication of the bolus, and the act of swallowing.