Nasopalatine Duct CystINCISIVE CANAL CYST

the most common nonodontogenic cyst of the oral cavity(in about 1% of the population).

arise from remnants of the nasopalatine duct, an embryologic structure connecting the oral and nasal cavities in the area of the incisive canal.

incisive canals begin on the floor of the nasal cavity on either side of the nasal septum,.........downward and forward to exit the palatal bone via a common foramen in the area of the incisive papilla

these canals contain .....1.nasopalatine ducts2.Nasopalatine nerve3.branches of the descending palatine and sphenopalatine arteries.

Although the pathogenesis of this lesion is still uncertain..... but.................. spontaneous cystic degeneration of remnants of the nasopalatine duct.

any age / most common in the fourth to sixth decades of life

The most common presenting symptoms .........swelling of the anterior palate, drainage, and pain

many lesions are asymptomatic

Fluctuant swelling of the anterior hard palate.

1.incisive canal type (intraosseous)

2.originating in the papilla palatina. (within soft tissue with no radiographic changes)

Almost all nasopalatine duct cysts occur within the incisive canal.

at any level between the nasal and the oral cavity

teardrop shape and shows a well demarcated, slightly sclerotic border.

Some cysts may have an inverted pear shape

The central incisors gave vital responses to pulp tests.

superimposition of the nasal spine.......classic heart shape

Radiographic features

cysts of the incisive papilla.....In rare instances in the soft tissues of the incisive papilla area without any bony involvement.

• a larger incisive canal cyst with a more ill defined border. 

Nasopalatine Duct Cyst

superimposition over the apex ofa central incisor.

differential diagnosis periapical lesions

the vitality of the teeth

The highly variable epithelial lining ...............

♦ Stratified squamous epithelium..........most common

♦ Pseudostratified columnarepithelium....approximately 1/3 cases

♦ Simple columnar epithelium

♦ Simple cuboidal epithelium

Histopathology

• Respiratory pseudostratified columnar epithelium(arrow1).

• The fibrous connective tissue capsule contains focal areas of chronic inflammation

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2

Cilia and goblet cells maybe found in association with columnar linings

Epithelial lining

cuboidal cells with an uninflamed capsule

.•Those originating higher in the canal are usually lined by respiratory epithelium

•those located toward tile oral cavity feature a squamous lining. 

The type of epithelium is mainly dependent upon the location of the lesion

the presence of numerous large nerves(arrow1) and blood vessels(arrow2).

(These, of course, represent the normal structures that pass through the incisive canal.)

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2

The contents of the cyst wall can be a helpful diagnostic aid.

moderate-sized nerves andsmall muscular arteries and veins

• Peripheral Nerve Bundles (40X10)

• Large Vein

In biopsy specimens from this area

( a normal component of the papilla palatina.)

Occasionally…irregular cartilage

• Bleeding Secondary to Surgical Procedure

• Mucous Glands