The Nasopalatine duct cyst develops within the jawbones. Its location is found to be in the median of the palate, and is generally anterior to first molars. It appears asymptomatic but sometimes might give rise to an elevation in the anterior part of the palate. It had been first described in 1914 by Meyer. Nasopalatine duct cysts are the most common non-odontogenic oral cyst of the oral cavity.
Nasopalatine Duct Cyst Causes
Trauma, mucous retention inside salivary gland ducts and infection of Nasopalatine ducts are believed to be the possible reasons for the development of this cyst. Spontaneous cystic degeneration of the residual ductal epithelium is another possible cause.
These cysts are believed to originate from the epithelial remains of the Nasopalatine duct. This Nasopalatine duct is the connection between the nasal cavity and anterior maxilla in a fetus that is growing. The development continues and this connection slowly narrows the bones of the anterior palate fuse. This leads to the formation of the incisive canals which contains the nerves, blood vessels and also the epithelial remains from the degenerated Nasopalatine ducts.
Nasopalatine Duct Cyst Symptoms
Nasopalatine duct cyst may not show any symptoms in their early stages when they are small. Large cysts cause a lot of trouble.
The symptoms which an affected individual experiences are:
- A salty taste in the mouth.
- Swelling on the anterior palate lingual to the maxillary central incisors in the area of the incisive papilla.
- The swelling may have a bluish color depending on how near the fluid it is to the surface.
- Burning sensation in the anterior portion of the maxilla.
- Divergence of central incisor roots.
- Overlapping of crowns
- Superimposition of nasal septum.
- Tooth movement might occur.
- Mucoid discharge.
Nasopalatine Duct Cyst Diagnosis
Nasopalatine duct cyst is examined through histopathology, radiography, and other imagery tests such as CT scan and MRI.
- The Nasopalatine cyst looks like a prominent round, ovoid or heart shaped structure present in the midline of the maxilla when observed through radiography.
- The radiographic diameter is usually 17.1 mm.
- It shows destruction of the floor of maxillary antrum.
- Roots of the central incisors show divergence.
- Reveals peripheral sclerosis.
Histological analysis provides a definitive diagnosis for this cyst.
Following are observed in this test:
- The cyst is observed to be surrounded by stratified squamous epithelium.
- It is also partially lined by pseudo stratified columnar epithelium.
- Bundles of nerves and blood vessels are in the cyst wall.
- Small salivary gland tissues, small masses of cartilage can also be found.
- An infected cyst will show chronic inflammatory cells throughout.
MRI and CT scans are done to distinguish this cyst from other lesions.
- CT scans reveal a midline location, smooth bony expansion of the lesion with sclerotic margins. The progressive growth of the cyst may exceed 60 mm in diameter.
- MRI scans show homogenous high-signal intensity on T2-weighted images. Intermediate signal intensity shows T1-weighted images in the region of the contents of Nasopalatine duct cysts.
Nasopalatine Duct Cyst Treatment
Nasopalatine duct cysts are treated by removing the lesion by palatal or buccal approach. Biopsy procedure also provides proper treatment. Large cysts are treated by marsupialization before enucleation. Recurrences of the cysts are very rare.
There might be a few complications associated with the surgery.
- Surgical removal of the long sphenopalaitne nerve might cause Paresthesia to the anterior palate.
- Complete bone regeneration inside the bony defect might take place after surgery.
- Perforation of the vestibular bone, maxillary sinus and nasal cavity might occur.
Large nasopalatine duct cysts if left untreated might resorb the roots of adjacent teeth and reveal the roots.