Chapter 5

Question 1

what is a developmental disorder

Answer 1

• failure during the process of cell division and differentiation into various tissues and structures
• some may be identified clinically, by radiographic exam, biopsy, or histologic examination

Question 2

what would quantify an anomaly or disorder

Answer 2

• excess
• lack of
• deformity of
• dependent on timing and length of disturbance

Question 3

what is an inherent disorder

Answer 3

• caused by an abnormality in genetic makeup

Question 4

what is a congenital disorder

Answer 4

• present at birth
• may be inherited or developmental
• cause of most congenital abnormalities is unknown

Question 5

what is ankyloglossia

Answer 5

• an extensive adhesion of the tongue to the floor of the mouth
• due to the complete or partial fusion of the lingual frenum
• some patients may have adverse effects, while others may have difficulty with speech
• it may just involve mucosa, or it may be muscular and thick

Question 6

how do we treat ankyloglossia

Answer 6

• frenectomy

- works nicely with a laser

Question 7

what are commissural lip pits

Answer 7

• epithelium-lined blind tracts located at the corners of the mouth (commissures)
• may be shallow or several millimeters deep
• congenital lip pits may also be observed near the midline of the vermillion border
• no tx

Question 8

what are congenital lip pits

Answer 8

• similar to commissural lip pits

- found at midline of lips

Question 9

what is a lingual thyroid

Answer 9

• a small mass of thyroid tissue located on the tongue
• results from the failure of the primitive thyroid tissue to migrate from its developmental location in the area of foramen cecum on the posterior portion of the tongue to its normal position in the neck
• appears as a smooth nodular mass posterior to the circumvallate papillae at the base of the tongue

Question 10

how do we treat lingual thyroid

Answer 10

• may be removed if it is obstructive, providing the patient has other functioning thyroid tissue

Question 11

what are developmental cysts

Answer 11

• odontogenic cysts: related to tooth development
• nonodontogenic cysts: not tooth related
• pseudocysts
• an abnormal fluid-filled epithelium-lined sac or cavity
• found throughout the body, including the head and neck region

Question 12

how are developmental cysts classified

Answer 12

• whether they are odontogenic or nonodontogenic

- also classified according to location, cause, origin of epithelial cells, and histologic appearance

Question 13

what is an intraosseous cyst

Answer 13

• occurs within the bone

Question 14

what is an extraosseous cyst

Answer 14

• occurs in soft tissue

Question 15

how do cysts within the bone appear in rad

Answer 15

• generally appear as well-circumscribed radiolucencies

- may appear as unilocular or multilocular

Question 16

what are the different classifications of odontogenic cysts

Answer 16

• dentigerous cyst
• eruption cyst
• primordial cyst
• odontogenic keratocyst
• calcifying odontogenic cyst

Question 17

what is a dentigerous cyst

Answer 17

• odontogenic cyst
• aka follicular cyst
• forms around the crown of an unerupted or developing tooth
• the epithelial lining originates from the reduced enamel epithelium after the crown has formed and calcified
• most commonly around the crown of an unerupted or impacted third molar

Question 18

how does a dentigerous cyst appear on rad

Answer 18

• a well defined, unilocular radiolucency around the crown of an unerupted or impacted tooth

Question 19

what is the histologic makeup of a dentigerous cyst

Answer 19

• the lumen is most characteristically lined with cuboidal epithelium surrounded by a wall of connective tissue

Question 20

what is the tx for a dentigerous cyst

Answer 20

• removal of the cyst

- some risk of cystic transformation into a neoplasm

Question 21

what is an eruption cyst and how do we treat it

Answer 21

• odontogenic cyst
• similar to a dentigerous cyst; found in the soft tissue around the crown of an erupting tooth
• tx: none, will erupt through it. can make an incision in cyst to help

Question 22

what is a primordial cyst

Answer 22

• odontogenic cyst
• develops in place of a tooth
• most commonly in place of a third molar
• most often seen in young adults and discovered on rad exam

Question 23

what is the histological surroundings of a primordial cyst

Answer 23

• the lumen is lined by a stratified squamous epithelium surrounded by parallel bundles of collagen fibers
• it may prove to be an odontogenic keratocyst or a lateral periodontal cyst

Question 24

how do we treat a primordial cyst

Answer 24

• surgical removal

- risk of recurrence depends on the diagnosis

Question 25

what is an odontogenic keratocyst

Answer 25

• odontogenic cyst
• characterized by histologic appearance and frequent recurrence
• the lumen of the cyst contains parakeratin
• most often seen in the mand third molar region
• can move teeth and cause resorption

Question 26

how do we treat an odontogenic keratocyst

Answer 26

• due to a high recurrence rate, surgical excision and osseous curettage are recommended to remove all cells
• after removal, the bone will refill the empty void

Question 27

what is a calcifying odontogenic cyst

Answer 27

• odontogenic cyst
• a non aggressive, cystic lesion lined by odontogenic epithelium
• closely resembles an ameloblastoma
• has a characteristic feature called ghost cells
• common in incisor region

Question 28

what is an epidermal cyst and what is the tx

Answer 28

• non odontogenic cyst
• a raised nodule on the skin of the face or neck
• may be noted intraorally on occasion
• histologic: lined by keratinizing epithelium that resembles the epithelium of the skin. the lumen is usually filled with keratin scales
• tx: surgical excision

Question 29

what is a simple bone cyst

Answer 29

• non odontogenic cyst
• a pathologic cavity in bone that is not lined with epithelium. not a true cyst. may be associated with trauma
• radiographic: well defined unilocular or multilocular radiolucency. characteristically shows scalloping around roots of teeth
• tx: curettage on the wall lining the void