Lab 6

Developmental cyst

Nasopalatine duct cyst: an intaosseous developmental cyst of

the midline of the anterior palate, derived from the island of

epithelium remaining after closure of the embryonic nasopalatine

duct.

• The nasopalatine duct cyst, also termed incisive canal cyst, arises from

embryonic remnants of the nasopalatine duct.

• Most of these cysts develop in the midline of the anterior maxilla near

the incisive foramen.

Radiographical features:

• The nasopalatine duct cyst present as a well-

circumscribed oval or heart-shaped radiolucency

located in the midline of the anterior maxilla

between the roots of the central incisors.

Nasolabial cyst:• A developmental cyst of the soft tissue

of the anterior mucobuccal fold beneath

the ala of the nose.

• most likely derived from remnants of the

inferior portion of the nasolacrimal duct.

• Also known as the naso-alveolar cyst

and the klestadt cyst.

• this rare condition occurs entirely in the

soft tissues of the anterior maxillary

vestibule, below the ala of the nose and

deep in the nasolabial crease (fold).

Clinical features• This cyst is a unilateral or occasionally bilateral painless soft tissue swelling.

• If the upper lip is retracted, this cyst also can be seen inta-orally as a swelling

located at the depth of the maxillary vestibule.

• Most of these cysts occur in the fourth and fifth decades of life and have a

female predilection of approximately 3 to 1.

Histology:

• the cyst is lined by a layer of pseudo

stratified columnar epithelium exhibiting

variable numbers of mucus (goblet) cells or

by a ductal type of cuboidal epithelium.

• A lining of stratified squamous epithelium

can be seen in some lesion.

• Some degree of folding of the cyst lining

and of the associated connective tissue is

often seen.

• A narrow zone of dense, homogeneous,

fibrous tissue is usually seen adjacent to the

epithelial lining.

• Inflammation is generally absent.

Clinical features

• The oral lymphoepithelial cyst is most commonly found on the

anterior floor of the mouth and on the posterior lateral borders

of the tongue. However, it can also occur on the ventral surface

of the tongue, soft palate, tonsillar pillars, and oropharynx.

• It is a symptomatic, yellow or tan, superficial submucosal mass

that usually measures less than 1 cm in diameter .

CERVICALLYMPHOEPITHELIAL CYST.MEDIUM-POWERED VIEW SHOWING A CYST LINED BY STRATIFIED

SQUAMOUS EPITHELIUM. NOTE THE LYMPHOID TISSUE IN THE CYST WALL.

THYROGLOSSAL DUCT CYST. SWELLING (ARROW) OF THE ANTERIOR MIDLINE OF THE NECK.

THYROGLOSSAL DUET CYST . CYST (TOP) LINED BY STRATIFIED SQUAMOUS EPITHELIUM. THYROID FOLLICLES CAN BE SEEN INTHE CYST WALL (BOTTOM).

DERMOID CYST. FLUCTUANT MIDLINE SWELLING IN THEFLOOR OF THE MOUTH.

DERMOID CYST. SQUAMOUS EPITHELIA L LINING (TOP).WITH HAIR FOLLICLE (F) AND SEBACEOUSGLANDS (S) IN THE CYST WALL.

EPIDERMOID CYST . FLUCTUANT NODULE AT THE LATERALEDGE OF TH EEYEBROW.

EPIDERMOID CYST. INFANT.

EPIDERMOID CYST. A. L OW-POWER VIEW SHOWING A KERATIN-FILLED CYSTIC CAVITY. B, HIGHPOWERED VIEW SHOWING STRAT IFIED SQUAMOUS EPITHELIAL LINING WITH ORTHOKERATIN PRODUCTION.

Heterotopic oral Gastrointestinal cyst:• The heterotopic oral gastrointestinal cyst is a rare and unusual developmental

entity .

• most commonly found in the tongue or the floor of the mouth of infants or

young children.

• The theory of undifferentiated endodermal entrapment during the fourth or fifth

week of embryonic development, followed by gastrointestinal differentiation.

• This cyst is treated by surgical excision; recurrence is uncommon.

PALATAL CYST OF NEWBORN EPSTEIN'S PEARL S. SMALL KERATIN -FILLED CYSTS AT THEJUNCTION OF THE HARD AND SOFT PALATES.

MEDIAN PALATAL CYST. WELL-CIRCUMSCRIBED RADIOLUCENCYAPICAL TO THE MAXILLARY INCISORS IN THE MIDLINE. AT SURGERY THE LESION WAS UNRELATED TO THE INCISIVE CANAL.

HEMIHYPERPLASIA. ENLARGEMENT OF THE RIGHT SIDE OF THE FACE.

HEMIHYPERPLASIA. SAME PATIENT AS DEPICTED IN. WITH ASSOCIATED ENLARGEMENT OF THE RIGHT HALF OF THE

TONGUE .

HEMIHYPERPLASIA. RADIOGRAPH OF THE SAME PATIENT. MANDIBLE AND TEETH ON THE RIGHT SIDE ARE ENLARGED.

PROGRESSIVE HEMIFACIAL ATROPHY. YOUNG GIRL WITHRIGHT-SIDED FACIAL ATROPHY.

CROUZON SYNDROME. OCULAR PROPTOSIS AND MID FACE HYPOPLASIA.

APERT SYNDROME. SYNDACTYLY OF THE HAND.

APERT SYNDROME. RADIOGRAPH SHOWING "MIDFACE HYPOPLASIA

APERT SYNDROME. ABNORMAL SHAPE OF THE MAXILLA,WITH SWELLINGS OF THE POSTERIOR LATERAL HARD PALATE, RESULTING IN PSEUDOCLEFT FORMATION.

MANDIBULOFACIAL DYSOSTOSIS. PATIENT EXHIBITS A HYPOPLASTIC MANDIBLE, DOWNWARDSLANTING PALPEBRAL FISSURES, AND EAR DEFORMITIES.