Joke Collection Website - Joke collection - Can you help me find a detailed oral structure? Used to learn phonetic symbols. Thank you.
Can you help me find a detailed oral structure? Used to learn phonetic symbols. Thank you.
The oral cavity is the initial part of the digestive tract. The anterior fissure communicates with the outside world and then continues to communicate with the pharynx through the pharyngeal isthmus. There are teeth, tongue and other organs in the mouth. The front wall of the oral cavity is the lip, the side wall is the cheek, the top is the palate, and the bottom of the oral cavity is the mucosa and muscles. The oral cavity is divided into an oral vestibule with an anterolateral part and an oral pillar with a posterior medial part by upper and lower dental arches. When the upper and lower teeth bite, the oral vestibule can communicate with the inherent oral cavity through the space behind the third molar. Clinically, when the patient's teeth are clenched, an opener or cannula can be placed through this passage to inject drugs or nutrients, and at the same time, tongue biting can be prevented.
(1) lips and cheeks
The oral lip constitutes the front wall of the oral cavity and is divided into upper lip and lower lip. The crack between the two lips is called mouth crack, and the joint between the two sides is called squabble. There is a vertical shallow groove on the median line of the upper lip, which is called human body. It is a unique structure of human beings. Coma patients often have acupuncture or acupressure stimulation here to wake them up.
Cheeks form two side walls of oral cavity, and the shallow groove between cheeks and upper lip is nasolabial groove.
(2) Taste
The palate forms the top of the mouth. The first 2/3 of it is hard palate, which is dominated by bone palate and covered with mucosa. The back of the soft palate leans backward, which is called pala- tine velum. The posterior margin of the palatal sail is free, and the center has a downward protrusion, which is called uvula. There are two pairs of mucosal folds on both sides of the uvula, which are connected with the base of the tongue and the lateral pharyngeal wall respectively, with a symmetrical velopharyngeal arch in front and a symmetrical velopharyngeal arch in the back. The fossa between the two arches is called tonsil fossa, which contains palatine tonsil. Palatal uvula, palatoglossal arch on both sides and tongue root together form pharyngeal isthmus, which is the dividing line between oral cavity and pharynx.
(3) Tongue
The tongue, located at the bottom of the mouth, is a muscular organ with the functions of feeling the taste, assisting in chewing and swallowing food and assisting in pronunciation.
1, the shape of the tongue is divided into upper and lower sides. It is called the back of the tongue, and its back is divided into the front 2/3 of the tongue body (boay of the tongue body) and the back 1/3 of the tongue root by a terminal groove, and the front end of the tongue body is called the tip of the tongue. There is a mucosal fold connected with the floor of the mouth on the sublingual midline, called lingual frenulum, and there are small mucosal bulges on both sides of its root, called hypoglossal caruncle, which is the opening of submandibular gland and sublingual gland. The posterior and lateral sides of hypoglossal nerve caruncle continue to be hypoglossal folds, and its deep surface is covered by sublingual glands.
2. The structure of tongue is mainly skeletal muscle, and its surface is covered with mucosa.
The mucosa on the back of the tongue is reddish with many small protrusions, which are called lingual papillae (1 lingual papillae). According to the difference of morphology and function, it can be divided into four types: filamentous papillae, the largest number, is white and has general sensory function; Fungal nipples are dark round and bright red. Thyroid papillae is the largest and arranged in front of sulcus. The human lobular papilla is a degenerated structure. The last three nipples contain taste receptors.
In the mucosa of the tongue root, there are small nodules of different sizes, which are composed of lymphoid tissue and are called lingual tonsils (1 lingual tonsils).
Tongue muscle is skeletal muscle, which is divided into internal muscle and external muscle. When the lingual muscle contracts, it changes the shape of the tongue. Change the position of the tongue when the extralingual muscle contracts. Genioglossus muscle is the most important extralingual muscle. Muscles start from both sides of the midline of mandibular body, and muscle fibers end in the tongue in a fan shape. Bilateral genioglossus muscles contract at the same time, pulling the tongue forward and downward (extending the tongue); When contracting unilaterally, it can extend to the opposite side. When one genioglossus muscle is paralyzed, the tip of the tongue is biased to the paralyzed side.
(4) teeth
The teeth are embedded in the alveoli of the upper and lower jaws and arranged in the dental arches of the upper and lower jaws respectively.
1, the shape of teeth is divided into crown, neck and root. The crown exposed to the mouth is white and shiny; Tooth root); Embedded in the alveolar cavity; The part between the crown and the root of the tooth is surrounded by the gum, which is called the neck of the tooth.
The inner cavity of a tooth is called a dental cavity, and the root canal of a tooth is located in the root and communicates with the alveolar cavity. There is dental pulp in the tooth cavity, which is rich in blood vessels and nerves. When the pulp is inflamed, it will cause severe pain.
2. Tooth structure The teeth are mainly composed of light yellow dentin, the crown surface is covered with a layer of white enamel, and the root and neck surface are covered with a layer of adhesive. Gingiva, periodontal ligament and alveolar bone together constitute periodontal tissue, which protects, supports and fixes teeth.
3. Name and eruption time of teeth There are two sets of teeth in one's life. After a person is born, deciduous teeth generally begin to erupt around 6 months, and 20 teeth grow around 3 years old. Primary teeth are divided into teeth, canine teeth and molars. 6-year-old deciduous teeth began to fall off and replaced with permanent teeth, 12 ~ 14 years old came out. Permanent teeth are divided into incisors, canines, premolars and molars. The third molar erupts late, and some people only erupt in adulthood, which is called delayed tooth, or even never erupts. 28-32 adult permanent teeth.
4. The arrangement of teeth is symmetrical with teeth. Clinically, in order to record the position of teeth, we use "+"to record the arrangement of teeth, Roman numerals I ~ V for primary teeth, and Arabic numerals 1-8 for permanent teeth.
(5) Oral glands
Salivary gland is the general name of all kinds of glands that open in the mouth. Oral glands are divided into two types, which can secrete saliva. Small salivary glands include labial glands and buccal glands. Large salivary glands include parotid gland, submandibular gland and sublingual gland.
The parotid gland is the largest of the three pairs of large salivary glands, slightly triangular and wedge-shaped, located in the anterior and inferior part of the external auditory canal. The parotid duct starts from the front of parotid gland, passes through the surface of masseter muscle at the lower finger of zygomatic arch, and finally passes through buccal muscle, and opens on the buccal mucosa opposite to the crown of maxillary second molar.
Submandibular gland is located in the deep surface of mandibular body, slightly oval, and the gland tube opens at sublingual caruncle.
The sublingual gland is located in the deep layer of hypoglossal nerve fold, and the gland tube opens at hypoglossal nerve mound and hypoglossal nerve fold.
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