GENERAL ANATOMY 2
COLLEGE OF DENTISTRY
MOUTH AND THE REGIONS SURROUNDING IT
LIPS
Two fleshy folds that circumscribe the mouth and close the buccal cavity in front. At the sides they unite
to form the commissures.
The lips consists of five layers:
1. Skin- fairly thick; contains hair follicles and sebaceous glands
2. Superficial fascia- loosely arranged; contains some fat
3. Orbicularis oris muscle- sphincter muscle of the mouth
4. Submucous tissue- contains vessels and mucous labial glands. An arterial circle is present (upper
and lower branches of the facial artery
5. Mucous membrane- innermost layer of the lip
MOUTH PROPER
The oral cavity is conveniently divided by the arch formed by the teeth and gums into the “oral vestibule”
which lies between the gums and the cheeks, and the “oral cavity proper” which lies behind and within the
arch of the teeth. They communicate with each other through the spaces in between the teeth and
retromolar space.
Boundaries of the ORAL VESTIBULE:
1. Anteriorly- the lips
2. Laterally- cheeks
3. Posteriorly and medially- teeth and gums
About the circumference of the oral vestibule, the superior and the inferior, cul-de-sacs are formed by the
reflection of the mucous membrane of the lips and the cheeks upon the upper and lower alveolar arches.
The Stensen’s or parotid duct opens into the oral vestibule on a small papilla located opposite the upper
second molar.
Boundaries of the ORAL CAVITY PROPER:
1. Anteriorly and laterally- teeth and gums
2. Superiorly- palate (hard and soft)
3. Inferiorly- tongue and floor of the mouth
4. Posteriorly- isthmus of fauces (opening to the pharynx)
, GENERAL ANATOMY 2
COLLEGE OF DENTISTRY
SUBLINGUAL REGION
The 2 sublingual regions make up the floor of the mouth. Each is represented as a deep groove lying
between the mandible and the root of the tongue and placed upon the mylohyoid and the hyoglossus
muscles. The anterior 2/3of the tongue rises from the floor, and the “lingual frenulum” appears as a
median fold which connects the tongue to the floor. On each side of the frenulum, the lingual vein appears
as a prominent blue line. At the tip of the frenulum will be found two small papillae where the opening of
the submaxillary salivary duct is found. The sublingual fold, a ridge of mucous membrane, passes laterally
and backward from the papilla and overlies the sublingual gland. Each sublingual compartment contains
the sublingual gland, part of the submaxillary gland, submaxillary duct, lingual and hypoglossal nerve and
the sublingual vessels.
SUBLINGUAL GLAND
Smallest of the salivary glands and rests upon the mylohyoid muscle in the sublingual fossa close to the
symphysis menti. Its posterior end is in contact with the anterior prolongation of the submaxillary gland.
The gland is indicated by the sublingual fold which is found between the alveolus and anterior part of the
tongue. It takes an oblique forward and inward course to the sublingual caruncle near the frenulum. It also
lines the mark of the submaxillary duct and the lingual nerve. The gland has many sublingual ducts
(Rivini’s) that open separately into the floor of the mouth, one of the larger ones on the posterior part
opens into or by the side of the submandibular gland.
SUBMAXILLARY (SUBMANDIBULAR) GLAND
Located at the submandibular fossa below the mylohyoid muscle. The submandibular duct (Wharton’s)
arises from the medial surface of the gland and accompanies it under the mylohyoid muscle; it passes
diagonally across the medial aspect of the sublingual gland and adheres to it. It opens in the sublingual
papilla beside the lingual frenulum.
BUCCAL CAVITY
Area between the inferior margin of the orbit and the lower jaw extending from the masseter muscle to the
fold of the nose and the commissure of the lip. The cheeks (buccae) resembles the lips in their structure,
having the same five layers:
1. Skin
2. Superficial fascia containing the zygomaticus major, risorius and platysma muscles; parotid duct,
branches of the facial and trigeminal nerves
3. Muscular layer –buccinator muscle covered by the buccopharyngeal fascia and is pierced by the
parotid duct.
4. Submucous layer containing mucous buccal glands
5. Mucous membrane
In the region of the cheek, the subcutaneous fat increases to form the so-called “sectorial fat pad” located
on the buccinator's muscle and partly under and in front of the masseter.
The facial artery is the only important vessel to the cheek. It crosses forward on the buccinator's muscle
and becomes the angular artery at the corner of the mouth.
COLLEGE OF DENTISTRY
MOUTH AND THE REGIONS SURROUNDING IT
LIPS
Two fleshy folds that circumscribe the mouth and close the buccal cavity in front. At the sides they unite
to form the commissures.
The lips consists of five layers:
1. Skin- fairly thick; contains hair follicles and sebaceous glands
2. Superficial fascia- loosely arranged; contains some fat
3. Orbicularis oris muscle- sphincter muscle of the mouth
4. Submucous tissue- contains vessels and mucous labial glands. An arterial circle is present (upper
and lower branches of the facial artery
5. Mucous membrane- innermost layer of the lip
MOUTH PROPER
The oral cavity is conveniently divided by the arch formed by the teeth and gums into the “oral vestibule”
which lies between the gums and the cheeks, and the “oral cavity proper” which lies behind and within the
arch of the teeth. They communicate with each other through the spaces in between the teeth and
retromolar space.
Boundaries of the ORAL VESTIBULE:
1. Anteriorly- the lips
2. Laterally- cheeks
3. Posteriorly and medially- teeth and gums
About the circumference of the oral vestibule, the superior and the inferior, cul-de-sacs are formed by the
reflection of the mucous membrane of the lips and the cheeks upon the upper and lower alveolar arches.
The Stensen’s or parotid duct opens into the oral vestibule on a small papilla located opposite the upper
second molar.
Boundaries of the ORAL CAVITY PROPER:
1. Anteriorly and laterally- teeth and gums
2. Superiorly- palate (hard and soft)
3. Inferiorly- tongue and floor of the mouth
4. Posteriorly- isthmus of fauces (opening to the pharynx)
, GENERAL ANATOMY 2
COLLEGE OF DENTISTRY
SUBLINGUAL REGION
The 2 sublingual regions make up the floor of the mouth. Each is represented as a deep groove lying
between the mandible and the root of the tongue and placed upon the mylohyoid and the hyoglossus
muscles. The anterior 2/3of the tongue rises from the floor, and the “lingual frenulum” appears as a
median fold which connects the tongue to the floor. On each side of the frenulum, the lingual vein appears
as a prominent blue line. At the tip of the frenulum will be found two small papillae where the opening of
the submaxillary salivary duct is found. The sublingual fold, a ridge of mucous membrane, passes laterally
and backward from the papilla and overlies the sublingual gland. Each sublingual compartment contains
the sublingual gland, part of the submaxillary gland, submaxillary duct, lingual and hypoglossal nerve and
the sublingual vessels.
SUBLINGUAL GLAND
Smallest of the salivary glands and rests upon the mylohyoid muscle in the sublingual fossa close to the
symphysis menti. Its posterior end is in contact with the anterior prolongation of the submaxillary gland.
The gland is indicated by the sublingual fold which is found between the alveolus and anterior part of the
tongue. It takes an oblique forward and inward course to the sublingual caruncle near the frenulum. It also
lines the mark of the submaxillary duct and the lingual nerve. The gland has many sublingual ducts
(Rivini’s) that open separately into the floor of the mouth, one of the larger ones on the posterior part
opens into or by the side of the submandibular gland.
SUBMAXILLARY (SUBMANDIBULAR) GLAND
Located at the submandibular fossa below the mylohyoid muscle. The submandibular duct (Wharton’s)
arises from the medial surface of the gland and accompanies it under the mylohyoid muscle; it passes
diagonally across the medial aspect of the sublingual gland and adheres to it. It opens in the sublingual
papilla beside the lingual frenulum.
BUCCAL CAVITY
Area between the inferior margin of the orbit and the lower jaw extending from the masseter muscle to the
fold of the nose and the commissure of the lip. The cheeks (buccae) resembles the lips in their structure,
having the same five layers:
1. Skin
2. Superficial fascia containing the zygomaticus major, risorius and platysma muscles; parotid duct,
branches of the facial and trigeminal nerves
3. Muscular layer –buccinator muscle covered by the buccopharyngeal fascia and is pierced by the
parotid duct.
4. Submucous layer containing mucous buccal glands
5. Mucous membrane
In the region of the cheek, the subcutaneous fat increases to form the so-called “sectorial fat pad” located
on the buccinator's muscle and partly under and in front of the masseter.
The facial artery is the only important vessel to the cheek. It crosses forward on the buccinator's muscle
and becomes the angular artery at the corner of the mouth.
