Oral Cavity Anatomy Quiz

Oral Cavity Anatomy

• The oral cavity is lined with a continuous mucous membrane, connecting to the skin near the vermillion border of the lips and the pharyngeal mucosa.
• The epithelium of the oral mucosa originates partially from ectoderm (lips, vestibules, gingiva, cheeks, palate, and floor of the mouth) and endoderm (tongue).

Oral Cavity Divisions

• The oral cavity is divided into two spaces by the alveolar processes and dental arches:
  • The vestibule (smaller space) is the area outside the teeth.
  • The oral cavity proper (larger space) includes the oral surfaces of the teeth and gingiva, hard and soft palate, and mucosa of the tongue and floor of the mouth. It also includes the posterior pillar of the fauces and tonsils.

Tongue Anatomy

• The tongue is a muscular body, with three regions:
  • Tip (Apex linguae)
  • Body (Corpus linguae)
  • Base (Radix linguae) - the posterior 2/3.
• The tip and body are located in the anterior 2/3 of the oral cavity, while the base extends into the pharynx.
• The tongue has a median sulcus (dividing the tongue into equal halves) and complex papillary characteristics.
• The tongue's surface is covered by specialized mucosa with a thick parakeratinized to keratinized epithelium mediating touch, temperature, and taste sensations.

Tongue Papillae

• The tongue has four types of papillae:
  • Filiform: slender, thread-like, keratinized extensions covering the anterior surface, providing tactile sensation and aiding in chewing.
  • Fungiform: smooth, round/mushroom-shaped, more numerous on the tip and sides of the tongue, with taste buds and mediating the sensation of sweet and salty tastes.
  • Circumvallate: large, dome-shaped, located at the posterior edge of the tongue (in a 'V' shape), containing taste buds for bitter taste.
  • Foliate: bilateral ridges at the posterior edge of the tongue, also containing taste buds, primarily mediating sour taste.

Taste Buds

• Taste buds are epithelial structures found within papillae (especially fungiform, foliate, and vallate).
• Composed of 30-100 spindle-shaped cells, with an opening (taste pore).
• Contain a variety of taste receptor cells.

Taste Cells

• Taste buds have taste cells (10–14 per taste bud) responsible for synthesis and secretion of pore substances, directly interacting with taste stimuli.
• Different types of taste cells are categorized by their structure and function.

Tongue Nerve Supply

• The anterior 2/3 of the tongue receives taste sensations from the chorda tympani branch of the 7th cranial nerve.
• The posterior 1/3 is innervated by the glossopharyngeal nerve.

Tongue Vasculature and Lymphatics

• The tongue receives arterial blood supply from the deep lingual artery (anterior 2/3) and dorsal lingual artery. (posterior 1/3).
• Lymph from the tongue's apex drains to the mental nodes, which connect to the submandibular and deep cervical nodes.

Teeth Structure and Classification

• Teeth can be categorized according to number of tooth sets into:
• Monophyodont: one set of teeth
• Diphyodont: two sets of teeth : humans and other mammals
• Polyphydont: multiple sets of teeth
• Based on the various shapes and functions, teeth are categorized into Incisors, Canines, Premolars, and Molars.
• The main components include enamel (hardest layer, covering the crown), dentin (bulk of the tooth), and cementum (covers the root).
• The pulp is a soft connective tissue at the tooth centre.

Supporting/Investing Tissues

• Gingivae (gum): oral mucosa surrounding teeth's neck.
• Periodontal ligament: fibrous connective tissue between the tooth root and alveolar bone.
• Alveolar bone: part of the maxilla or mandible, forms the socket where tooth roots are embedded.

Salivary Glands

• Salivary glands are exocrine glands producing and secreting saliva into the oral cavity..
• Two major types are:
  • Parotid gland
  • Submandibular gland
  • Sublingual gland
• Other, minor/intrinsic glands, include labial, buccal, palatine, lingual, Von Ebner's, and glossopalatine glands.

Tonsils

• The tonsils are collections of lymphoid tissue forming a protective ring of Waldeyer.
• Important for immune functions (including immunization) providing lymphocytes and immune response.
  • Two palatine tonsils
  • Two lingual tonsils
  • One pharyngeal tonsil/adenoid

Paraoral Tissues

• Structures functionally associated with the oral cavity.
• Important in mastication (chewing), ingestion, swallowing (deglutition), taste sensation and respiration.

Functions of Oral Cavity

• Mastication: The act of chewing and breaking down food.
• Ingestion: Taking in food using lips and oral structures.
• Deglutition (Swallowing): The process of moving food from the mouth to the esophagus.
• Taste: Perceiving different tastes.
• Speech: Forming sounds and language.
• Digestion: Preliminary physical and chemical breakdown of food (mechanical and by enzymes).
• Respiration: Utilizing the oral cavity for respiration when nasal passages are blocked.
• Protection: A role for the tonsils (fighting against bacteria/pathogens).

Test your knowledge of the anatomy of the oral cavity, including its divisions and the structure of the tongue. This quiz covers important aspects such as the mucous membrane, epithelium origins, and the different regions of the tongue. Discover how well you understand these foundational elements of oral anatomy.