sub-mandibular glands and submandibular calculi

Submandibular glands

• paired salivary glands
• smaller than parotid glands but larger than sublingual glands
• hook shaped, divided to deep and superficial part
• larger arm

o larger arm of hook is below the mylohyoid muscle therefore outside the boundaries of the oral cavity

o superficial part of the gland

o against a shallow impression on the medial side of the mandible

· smaller arm

o deep part

o loops around inferior margin of the mylohyoid muscle to enter and lie within the floor of the oral cavity

o lateral to the surface of the hyoglossus muscle

· submandibular duct

o emerges from the medial side of the deep part of the gland in oral cavity

o passes forward to open on the summit of a small sublingual papilla inside base of frenulum of tongue

o the lingual nerve loops under the submandibular duct from lateral to medial

o nerve descends anteromedially through floor of oral cavity into tongue

vessels

· supplied by branches of facial and lingual arteries

· veins drain into lingual and facial veins

· lymph of submandibular glands drain into submandibular nodes and then into deep cervical nodes

innervation

• chorda tympani branch of facial nerve

Salivary duct calculus is a concretion of mostly calcium mineral salts (calculus) that forms within the ducts. The resulting blockage and inflammation (sialitis) causes immense pain on eating when saliva production increases and infection of the salivary gland may ensue.

The majority form in the submandibular gland.

Where do salivary gland stones occur?

About 8 in 10 salivary stones form in one of the submandibular glands. It is thought that the 'uphill' drainage and the slightly thicker saliva that is made in these glands is why stones are more likely to form there. (The larger parotid glands drain saliva sideways into the mouth. They also make saliva that is 'thinner' than the submandibular glands.)

What are the symptoms of salivary stones?

The common symptoms are pain and swelling of the affected gland at mealtimes. This occurs if the stone completely blocks a duct. You normally make extra saliva during a meal which pours into the mouth. However, the saliva cannot pass into the mouth if the duct is blocked by a stone. The pain can be sudden and intense just after starting a meal. Swelling soon follows. The pain and swelling ease over about 1-2 hours after a meal.

However, most stones do not block a duct completely. A stone may only partially block saliva flow, or not block the flow at all if it is embedded in the body of the gland. In these situations the symptoms can vary and include one or more of the following.

• Dull pain from time to time over the affected gland.
• Swelling of the gland. Swelling may be persistent, or vary in size from time to time.
• Infection of the gland may occur causing redness and pain. This may develop into an abscess (ball of infection and pus) and make you feel quite unwell.
• No symptoms at all. A stone may be found by chance on an x-ray taken for another reason