ANATOMY OF ORAL CAVITY
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Sublingual (below the tongue) glands – smallest of the three paired salivary glands,
produce primarily mucous secretions.
Oral cavity (mouth) first part of the digestive tract.
Lips – muscular structures formed mostly by orbicularis oris muscle. Outer surfaces are
covered by skin.
Saliva – a versatile fluid.
Transparent epithelium giving the lips a reddish-pink appearance.
Buccinator muscles – cheeks from lateral wall of the oral cavity located within the cheeks.
Mastication (chewing) – process of mechanical digestion. Lips and cheeks are important in
the process of mastication.
Tongue – a large muscular organ that occupies most of the oral cavity. Its attachment is in
the posterior part of the oral cavity.
Frenulum – anterior attachment of to the floor of mouth by a thin fold of tissue.
The anterior two-thirds of the tongue is covered by papillae.
The posterior portion contains large amount of lymphatic tissue.
Maltose and isomaltose have a sweet taste.
Cellulose – cell walls composed primarily of the
polysaccharide.
Lysozyme – anti bacterial enzyme.
Pharynx (throat) consists of three parts: nasopharynx, oropharynx, and the
laryngopharynx.
32 teeth in adult located in the mandible and maxillae.
Teeth divide into four quadrant: right upper, left upper, right lower, left lower.
Each quadrant contains 1 central and lateral incisor (to cut); one canine (dog); first and
second premolars (molaris, a millstone); first, second, and third molars. The third morals
are called wisdom teeth. (in adults)
Teeth of adults are called Permanent teeth (secondary teeth) – replacement of 20
primary teeth (deciduous teeth) also called milk or baby teeth.
Each tooth consists of 3 regions: a crown with one or more cusps, neck, and root.
Pulp cavity – center of the tooth.
Salivary amylase – digestive enzyme.
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Pharyngeal constrictor muscles – posterior walls of the oropharynx and
laryngopharynx.
Esophagus (gullet) – a muscular tube. 25 cm long and lies on anterior and posterior
to the trachea within the mediastinum.
Esophageal sphincters - located at the upper and lower ends of the esophagus.
Cardiac sphincter is sometimes called lower esophageal sphincter.
Pulp – filled with blood vessels, nerves, and connective tissue.
Dentin (dens, tooth) – a living, cellular, calcified tissue surrounding the pulp cavity.
Enamel – an extremely hard, acellular substance covering the dentin of the tooth crown.
It protects the tooth against abrasion and acids produced by bacteria in the mouth.
Cementum – it covers the surface of the dentin in the root.
Swallowing (deglutition) has three phases: voluntary phase, pharyngeal
phase, esophageal phase.
Epiglottis (upon the glottis, opening of the larynx)
Peristaltic (around+staltis, constriction) waves – where the muscular
contractions of the esophagus occur.
Alveoli (sockets) – a place where teeth are held.
Gingiva (gums) – a dense fibrous connective tissue and moist stratified squamous
epithelium.
Periodontal (around the teeth) ligaments – secures the teeth in the alveoli by embedding
into the cementum.
Dental caries (tooth decay) – breakdown of enamel by acids produced by bacteria on the
tooth surface.
Periodental disease – an inflammation and degeneration of the periodontal ligaments,
gingiva, and alveolar bone. Infection may occur on tooth, bone, or in the surrounding soft
tissues.
Stomach – houses food for mixing with hydrochloric acid and other secretions.
An enlarged segment of the digestive tract in the left superior part of the
abdomen.
Gastroesophageal opening – opening from the esophagus into the stomach.
Cardiac region – stomach region.
Fundus – most superior part of the stomach.
Body – largest part of the stomach.
Greater and lesser curvature – formation when body turns to the right.
Palate (roof of the oral cavity) – separates the oral cavity from the nasal cavity and
prevents food from passing into the nasal cavity during chewing and swallowing.
Pyloric (gatekeeper) opening – opening into the small intestine.
Hard palate – bones in the anterior.
Pyloric sphincter – a thick ring of smooth muscle surrounding the pyloric opening.
Soft palate – bones in the posterior.
Pyloric region – region of the stomach near the pyloric opening.
Uvula (a grape) – a posterior extension of the soft palate.
Rugae (wrinkles) – the submucosa and mucosa of the stomach are thrown into
large folds.
Tonsils – located in the lateral posterior walls of oral cavity.
3 major pairs of salivary glands: parotid glands, submandibular glands, and sublingual
gland.
Saliva – a mixture of serous (watery) and mucous fluids.
Parotid (beside the ear) glands – a serous glands located anterior of the ear.
Mumps – an inflammation of the parotid gland caused by a viral infection.
Submandibular (below the mandible) glands – produce more serous than mucous
secretions.
Gatric pits – numerous tubelike of the mucosal surface. Openings for the
gastric glands.
5 groups of epithelial cells:
Surface mucuos cells – inner surface of the stomach and lining gastric pits,
produces mucus.
Mucous neck cells – produce mucus. “located at the gastric glands”
Parietal cells – produce hydrochloric acid and intrinsic factor. “”
Endocrine cells – produces regulatory chemicals. “”
Chief cells – produce pepsinogen, a precursor of the protein-digesting enzyme
pepsin (pepsis, digestion) “”