Ranula: Definition, Causes, Symptoms and Treatment of This Type of Oral Cyst

It is a clinical term for a mucocele or mucus retention cyst located on the floor of the mouth.

This form of retention cyst is generally due to the obstruction of the ducts of the submaxillary or sublingual glands, which increases slowly on one side of the mouth.

The ranula is also called a sublingual cyst.

There are two types of ranula: the simple (or intraoral) ranula and the deep (or sunken) ranula.

The simple ranula is the most common or simple variant that is generally limited to the oral cavity.

The cervical ranula that can extend from the sublingual space around or through the mylohyoid muscle to the submandibular space, even invading the tissues of the neck.

Although both types of ranulae are similar, each type has a distinctive clinical appearance and behavior.

Both variants affect men and women of any age, including newborns.

Although these pseudocysts are generally unilateral, isolated cases of simple or deep bilateral ranulas have been documented.

The ranula must be distinguished from lymphangiomas that arise in a similar location on the floor of the mouth.

Lymphangiomas also have a tendency to infiltrate and insinuate between structures in the neck and are difficult to remove surgically.

Other tumors, such as lipomas and dermoid cysts, rarely develop on the floor of the mouth and can only be excluded by biopsy.

Causes of ranula

These injuries can be acquired or congenital, but these injuries also occur as a result of trauma or obstruction of the excretory duct of the salivary gland and mucin spillage into the surrounding soft tissues.

Saliva moves from a salivary gland through small tubes (ducts) into the mouth.

One of these ducts can be damaged or blocked, a blow to the face can also rupture the duct, then the mucus leaks, builds up, walled in, causing a cyst-like swelling.

A similar buildup occurs when the duct has become blocked.

The symptoms

Mucoceles often arise on the inside of the lower lips, on the gums, on the roof of the mouth, or under the tongue. Those that form on the floor of the mouth are called ranulas.

Ranulas are fluctuating masses that occur on one side of the midline of the floor of the mouth and are so named because of their resemblance to the swollen underside of a frog’s belly.

The ranula usually presents as a gray or bluish, shiny swelling that can reach a large size (more than 5 cm in diameter) and can insinuate between the structures in the neck.

People with an oral ranula may complain of swelling of the floor of the mouth which is usually painless.

The mass can interfere with speech, chewing, breathing, and swallowing due to the upward and medial displacement of the tongue.

When the oral ranulas are large, the tongue can put pressure on the lesion, which can interfere with the submandibular salivary flow.

As a result, signs and symptoms of an obstructive salivary gland may appear, such as pain or discomfort when eating, a feeling of fullness at that site, and increased swelling of the submandibular gland.

Ranula treatment

These are the two types of treatment that a doctor or dentist uses most often: enucleation and marsupialization.

Enucleation

Enucleation is the complete removal of the cyst – the benefit is that all cyst tissue is available for histological examination, and the cyst cavity usually heals without complications with minimal aftercare.

However, enucleation is potentially problematic if the cyst affects the apices of adjacent vital teeth, as surgery can deprive the teeth of their blood supply and render them non-vital.

Marsupialization

Marsupialization is the partial removal of the cyst – the benefit is that it is somewhat less invasive than enucleation and the vitality of the tooth is preserved, but it requires considerable aftercare and good cooperation from the patient to keep the cavity clean while it resolves .

In order to keep the cavity open, a plug or acrylic is usually inserted into the opening, often attached to an acrylic denture or splint.

The plug stops most of the food that accumulates in the cavity, but the patient still needs to clean the cavity after each meal.

Healing is slower than after enucleation: the cavities of marsupialized cysts can take up to six months to close.

The other disadvantage of marsupialization is that not all of the cyst lining is available for histopathological examination, and this could lead to a misdiagnosis.