ORPTH ADONS ODNTGN CYSTS TUMRS

Question 1

1. ________ is also known as follicular cyst.
   (a) Odontogenic keratocyst
   (b) Calcifying odontogenic cyst
   (c) Lateral periodontal cyst
   (d) Dentigerous cyst

Answer 1

(d) Dentigerous cyst is a cyst that originates by the separation
of the follicle from around the crown of an unerupted tooth,
hence the name follicular cyst. This is the most common
type of developmental odontogenic cyst, making up about
20 percent of all epithelium-lined cysts of the jaws

Question 2

2. A dentigerous cyst develops due to collection of fluid between
   _________ and tooth surface.
   (a) Reduced dental epithelium
   (b) Stellate reticulum
   (c) Internal dental epithelium
   (d) External dental epithelium

Answer 2

(a) The dentigerous cyst encloses the crown of an unerupted
tooth and is attached to the tooth at the cementoenamel
junction. The pathogenesis of this cyst is uncertain, but
apparently it develops by accumulation of fluid between
the reduced enamel epithelium and the tooth crown.

Question 3

3. The tooth most commonly involved by dentigerous cyst is
   (a) Maxillary canine
   (b) Maxillary 3rd molar
   (c) Mandibular 2nd premolar
   (d) Mandibular 3rd molar

Answer 3

(d) Although dentigerous cysts may occur in association
with any unerupted tooth, most often they involve
mandibular third molars. Other relatively frequent sites
include maxillary canines, maxillary third molars, and
mandibular second premolars. Dentigerous cysts rarely
involve unerupted deciduous teeth. Occasionally, they are
associated with supernumerary teeth or odontomas.

Question 4

4. Which one of the following is not a radiographic variety of
   dentigerous cyst?
   (a) Central (b) Collateral
   (c) Lateral (d) Circumferenti

Answer 4

(b) The most common variant of dentigerous cyst called central
variety, manifests as a cyst surrounding the crown of the
tooth with the crown projecting into the cyst. The lateral
variety is usually associated with mesioangular impacted
mandibular third molars that are partially erupted. In
this variant, the cyst grows laterally along the root surface
and partially surrounds the crown. In the circumferential
variant, the cyst surrounds the crown and extends for some
distance along the root so that a significant portion of the
root appears to lie within the cyst.

Question 5

5. A well-defined radiolucent lesion attached to the neck of an
   impacted mandibular third molar in a 20-year-old male is most
   likely to be
   (a) Dentigerous cyst
   (b) Odontogenic keratocyst
   (c) Lateral periodontal cyst
   (d) Calcifying odontogenic cyst

Answer 5

(a) Radiographically, the dentigerous cyst typically shows a
unilocular radiolucent area that is associated with the crown
of an unerupted tooth. The radiolucency usually has a welldefined
and often sclerotic border, but an infected cyst may
show ill-defined borders

Question 6

6. Multiple odontogenic keratocysts, basal cell carcinomas and
   bifid ribs are features of ________ syndrome.
   (a) Gardner (b) Gorlin-Goltz
   (c) Grinspan (d) Kelly Paterson

Answer 6

(b) Nevoid basal cell carcinoma syndrome (Gorlin-Goltz
syndrome) is an autosomal dominant condition. The chief
components are multiple basal cell carcinomas of skin,
odontogenic keratocysts, intracranial calcification, and rib
and vertebral anomalies

Question 7

7. Which one of the following odontogenic cysts grows in an
   anteroposterior direction within the medullary spaces of bone?
   (a) Dentigerous cyst (b) Odontogenic keratocyst
   (c) Gingival cyst of adults (d) Radicular cyst

Answer 7

(b) Odontogenic keratocysts tend to grow in an anteroposterior
direction within the medullary cavity of the bone without
causing obvious bone expansion. This feature may be useful
in differential clinical and radiographic diagnosis because
dentigerous and radicular cysts of comparable size are
usually associated with bony expansion.

Question 8

8. “Picket fence” or “Tombstone” appearance of basal cell layer of
   cyst lining is a characteristic feature seen in _________.
   (a) Odontogenic keratocyst
   (b) Dentigerous cyst
   (c) Radicular cyst
   (d) Lateral periodontal cyst

Answer 8

(a) Microscopically, the epithelial lining of OKC is composed
of a uniform layer of para/orthokeratinized stratified
squamous epithelium, usually 6–8 cells in thickness. The
basal epithelial layer is composed of a palisaded layer
of cuboidal or columnar epithelial cells, which are often
hyperchromatic. This palisading of basal layer imparts it
the typical “tombstone/picket fence” appearance.

Question 9

9. All of the following statements except _______ are true regarding
   odontogenic keratocyst
   (a) Seen primarily in mandibular molar—Ascending ramus
   region
   (b) Epithelial lining is thin and friable
   (c) Originates from cell rests of Malassezia
   (d) Epithelial lining is keratinized

Answer 9

(c) The odontogenic keratocyst is a distinctive form of
developmental odontogenic cyst that arises from cell rests
of the dental lamina, called cell rests of Serres.

Question 10

10. Which one of the following is an important factor in the
    recurrence of odontogenic keratocysts?
    (a) Presence of exudate in the cyst lumen
    (b) Presence of inflammation in connective tissue wall
    (c) Friable and thin epithelial lining
    (d) Development of new cysts from the cell rests of Malassezia
    in the vicinity

Answer 10

(c) Causes for recurrence of OKC are many, viz. thin, friable
cyst lining, incomplete removal of cyst and development
of new cyst from the rests of dental lamina in the vicinity.

Question 11

11. All of the following except _____________ are examples of
    developmental odontogenic cysts.
    (a) Radicular cyst (b) Calcifying odontogenic cyst
    (c) Gingival cyst of adults (d) Lateral periodontal cyst

Answer 11

(a) Radicular cyst is an inflammatory odontogenic cyst
unlike other cysts which are developmental in origin.
Thus a radicular cyst develops due to inflammation in
the periapical region owing to either pulp inflammation,
trauma, etc.

Question 12

12. A primordial cyst is now believed to represent
    (a) Calcifying odontogenic cyst
    (b) Odontogenic keratocyst
    (c) Lateral periodontal cyst
    (d) Botryoid odontogenic cyst

Answer 12

(b) In the older literature, a primordial cyst was believed to arise
due to degeneration of dental organ epithelium before the
development of dental hard tissues. Thus it was supposed
to develop in place of a tooth. However, all recent evidence
indicates that the entity labeled primordial cyst is in fact an
odontogenic keratocyst.

Question 13

13. Small, superficial, keratin filled cysts that are found on the
    alveolar mucosa of infants are most likely to be
    (a) Median mandibular cyst
    (b) Nasopalatine duct cyst
    (c) Gingival cyst of the newborn
    (d) Eruption cyst

Answer 13

(c) These cysts arise from remnants of the dental lamina. They
are common lesions. Similar inclusion cysts, e.g. Epstein’s
pearls and Bohn’s nodules are also found in the midline of
the palate or laterally on the hard and soft palate

Question 14

14. Spot the only fissural/inclusion cyst amongst the below given
    cysts
    (a) Lateral periodontal cyst
    (b) Nasopalatine duct cyst
    (c) Glandular odontogenic cyst
    (d) Dentigerous cyst

Answer 14

(b) It is the most common of the nonodontogenic fissural cysts,
occurring exclusively on the midline of anterior maxilla. It
is believed to arise from spontaneous cystic degene-ration
of the residual nasopalatine duct epithelium.

Question 15

15. An eruption cyst is a soft tissue analogue of
    (a) Radicular cyst (b) Gingival cyst of newborn
    (c) Dentigerous cyst (d) Odontogenic keratocyst

Answer 15

(c) This cyst develops as a result of separation of dental follicle
from around the crown of an erupting tooth that is within
the soft tissues overlying the alveolar bone.

Question 16

16. A smooth, translucent swelling on gingival mucosa overlying the
    crown of an erupting tooth is suggestive of
    (a) Parulis (b) Eruption cyst
    (c) Gingival cyst of adults (d) Gingival cyst of newborn

Answer 16

(b) Although the cyst may occur with any erupting tooth, the
lesion is most commonly associated with the first permanent
molars and the maxillary incisors. Surface trauma may result
in a considerable amount of blood in the cystic fluid, which
imparts a blue to purplish-brown color to the lesion. Such
lesions sometimes are referred to as eruption hematomas

Question 17

17. Which amongst the following cysts has a predilection for
    occurrence in mandibular canine-premolar region?
    (a) Gingival cyst of adults (b) Gingival cyst of newborn
    (c) Radicular cyst (d) Dentigerous cyst

Answer 17

(a) Gingival cysts of the adult are most commonly found in
patients in the 5th and 6th decades of life and are almost
invariably located on the facial gingiva or alveolar mucosa.
Maxillary gingival cysts are usually found in the incisor,
canine and premolar areas

Question 18

18. Botryoid odontogenic cyst is a variant of which of the following
    cysts?
    (a) Gingival cyst of adults
    (b) Lateral periodontal cyst
    (c) Odontogenic keratocyst
    (d) Calcifying odontogenic cyst

Answer 18

(b) Occasionally a lateral periodontal cyst may have a polycystic
appearance. Such examples have been termed botryoid
odontogenic cysts. Grossly and microscopically they show
a grape-like cluster of small individual cysts. These lesions
are generally considered to represent a variant of the lateral
periodontal cyst, possibly due to cystic degeneration and
subsequent fusion of adjacent foci of dental lamina rest

Question 19

19. Which one of the following cysts is considered to be a soft tissue
    counterpart of lateral periodontal cyst?
    (a) Gingival cyst of newborn
    (b) Radicular cyst
    (c) Calcifying odontogenic cyst
    (d) Gingival cyst of adults

Answer 19

(d) The gingival cyst of the adult is considered to represent the
soft tissue counterpart of the lateral periodontal cyst, being
derived from rests of the dental lamina. The diagnosis of
gingival cyst of the adult should be restricted to lesions with
the same histopathological features as those of the lateral
periodontal cyst.

Question 20

20. Carcinoma arising within the odontogenic cyst linings is a
    complication seen most commonly in which cyst?
    (a) Dentigerous cyst
    (b) Odontogenic keratocyst
    (c) Lateral periodontal cyst
    (d) Radicular cyst

Answer 20

(a) Several potential complications must be considered in
dentigerous cysts. The lining of a dentigerous cyst might
undergo neoplastic transformation to an ameloblastoma.
Rarely, a squamous cell carcinoma may arise in the lining of
a dentigerous cyst. It is also possible for some intraosseous
mucoepidermoid carcinomas to develop from mucous cells
in the lining of a dentigerous cyst.

Question 21

21. A lateral periodontal cyst must be distinguished radiologically
    from which other odontogenic cyst?
    (a) Lateral dentigerous cyst (b) Collateral keratocyst
    (c) Epstein’s pearls (d) Eruption cyst

Answer 21

(b) The radiographic features of the lateral periodontal cyst are
not diagnostic. An odontogenic keratocyst that develops
between the roots of adjacent teeth may show identical
radiographic findings. An inflammatory radicular cyst that
occurs lateral to a root in relation to an accessory foramen
or a cyst that arises from periodontal inflammation also may
mimic a lateral periodontal cyst radiographically

Question 21

22. A median palatal cyst arises from
    (a) Epithelium entrapped along the line of fusion of palatal
    processes of maxilla
    (b) Cystic degeneration of remnants of nasopalatine duct
    (c) Cystic degeneration of rests of dental lamina
    (d) Cystic degeneration of epithelial rests of Malassezia

Answer 21

(a) This cyst is commonly located in the midline of hard palate
and may enlarge over a period of time. It is lined by stratified squamous epithelium overlying a dense, chronically
inflamed connective tissue wall

Question 22

23. Gorlin cyst is more commonly referred to as
    (a) Odontogenic keratocyst
    (b) Calcifying odontogenic cyst
    (c) Lateral periodontal cyst
    (d) Glandular odontogenic cyst

Answer 22

(b) The calcifying odontogenic cyst is an uncommon lesion,
widely considered by many to represent a cyst while some
investigators prefer to classify it as a neoplasm. In fact the
latest WHO classification (2005) of odontogenic tumors
places this cyst in the category of tumors and has re-named
it as calcifying cystic odontogenic tumor.

Question 23

24. A common odontogenic tumor, odontoma is most commonly
    associated with
    (a) Calcifying odontogenic cyst
    (b) Dentigerous cyst
    (c) Odontogenic keratocyst
    (d) Radicular cyst

Answer 23

(a) The COC may be associated with other recognized
odontogenic tumors, especially odontomas. However,
adenomatoid odontogenic tumors and ameloblastoma have
also been associated with COC. The WHO Classification
of Odontogenic Tumors groups the COC along with
all its variants as an odontogenic tumor rather than an
odontogenic cyst.

Question 24

25. Histological features of thin epithelial lining, ameloblast-like
    basal cell layer with overlying layers resembling stellate reticulum and abundant ghost cell within the epithelial lining are suggestive
    of
    (a) Dentigerous cyst
    (b) Radicular cyst
    (c) Calcifying odontogenic cyst
    (d) Odontogenic keratocyst

Answer 24

(c) The lining of COC consists of odontogenic epithelium of
4–10 cells in thickness. The basal cells of the epithelial lining
may be cuboidal or columnar and are similar to ameloblasts.
The overlying layer of loosely arranged epithelium may
resemble the stellate reticulum of an ameloblastoma. The
most characteristic histopathological
feature of the COC is
the presence of variable numbers of ghost cells within the
epithelial component

Question 25

26. A swelling of the upper lip lateral to the midline resulting in
    elevation of the ala of the nose is most likely to be
    (a) Nasopalatine duct cyst
    (b) Nasolabial cyst
    (c) Medial mandibular cyst
    (d) Globulomaxillary cyst

Answer 25

(b) The nasolabial cyst is a rare developmental (fissural)
cyst that occurs in the upper lip lateral to the midline.
The enlargement often elevates the mucosa of the nasal
vestibule and obliterates the maxillary mucolabial fold.

Question 26

27. Which one of following odontogenic cysts is not usually
    associated with an unerupted tooth?
    (a) Dentigerous cyst (b) Eruption cyst
    (c) Gingival cyst of adults (d) Calcifying odontogenic cyst

Answer 26

(c) The gingival cyst of adults is a developmental odontogenic
cyst derived from the remnants of dental lamina and shows
a striking predilection to occur in the mandibular canine
and premolar area

Question 27

28. Spot the only inflammatory odontogenic cysts amongst the below
    given cysts
    (a) Calcifying odontogenic cyst
    (b) Odontogenic keratocyst
    (c) Lateral periodontal cyst
    (d) Buccal bifurcation cyst

Answer 27

(d) The buccal bifurcation cyst is classified as an inflammatory
odontogenic cyst that characteristically develops
on the buccal aspect of the mandibular first permanent
molar. It has been speculated that when the tooth erupts,
an inflammatory response may occur in the surrounding
follicular tissues that stimulates cyst formation.

Question 28

29. Select a false statement regarding calcifying odontogenic cyst
    from below given statements
    (a) Numerous ghost cells are seen in connective tissue wall
    (b) It is seen mostly in the anterior maxilla and mandible
    (c) Usually associated with an impacted/unerupted tooth
    (d) Cyst lining appears ameloblastomatous

Answer 28

(a) The most characteristic histopathological feature of COC
is presence of ghost cells within the epithelial component These eosinophilic ghost cells are altered epithelial cells
characterized by the loss of nuclei with preservation of the
basic cell outline.

Question 29

30. Microscopic features of ___________ in some areas sometimes
    resemble those of a low grade mucoepidermoid carcinoma.
    (a) Buccal bifurcation cyst
    (b) Nasopalatine duct cyst
    (c) Sialo-odontogenic cyst
    (d) Gingival cyst of the newborn

Answer 29

(c) The glandular odontogenic cyst is a rare developmental
odontogenic cyst that can show aggressive behavior.
Generally accepted as being of odontogenic origin, it also
shows glandular features. The GOC is lined by squamous
epithelium of varying thickness. The fibrous cyst wall is
usually devoid of any inflammatory cell infiltrate. The
superficial epithelial cells lining the cyst cavity appear
cuboidal or columnar and have an irregular and sometimes
papillary surface. Occasionally cilia may be noted. Due to
presence of mucous cells and pools of mucin in the wall,
features of low grade mucoepidermoid carcinoma are
mimicked

Question 30

Which one of the following does not contribute to histogenesis
of ameloblastoma?
(a) Developing dental papilla
(b) Developing dental organ
(c) Epithelial lining of odontogenic cyst
(d) Rests of dental lamina

Answer 30

(a) Ameloblastomas are slow-growing, locally invasive tumors
that run a benign course in most cases. Theoretically, they
may arise from rests of dental lamina, from a developing
enamel organ, from the epithelial lining of an odontogenic
cyst, or from the basal cells of the oral mucosa.

Question 31

________ is the most common odontogenic tumor.
(a) Ameloblastoma
(b) Pindborg tumor
(c) Adenomatoid odontogenic tumor
(d) Odontoma

Answer 31

(d) Odontoma/odontome is the most common odontogenic
tumor, while ameloblastoma is the most common odontogenic
neoplasm. A tumor refers to any swelling, which
in case of odontoma is developmental in nature, i.e. a
hamartoma.

Question 32

Which amongst the following histological variants of ameloblastoma
is considered to be the most aggressive clinically?
76 MCQs in Oral Pathology
(a) Basal cell (b) Granular cell
(c) Desmoplastic (d) Acanthomatous

Answer 32

(b) Although originally this variant was considered to represent
an aging or degenerative change in long-standing lesions,
this variant has been seen in young patients and in clinically
aggressive tumors.

Question 32

A mixed radiopaque-radiolucent appearance is typically seen in
________ variant of ameloblastoma.
(a) Plexiform (b) Basal cell
(c) Desmoplastic (d) Granular cell

Answer 32

(c) Radiographically, this type usually resembles a fibroosseous
lesion because of its mixed radiolucent/radiopaque
appearance. This mixed radiographic appearance is due
to osseous metaplasia within the dense fibrous septa that
characterize the lesion and not because the tumor itself is
producing a mineralized product.

Question 33

Select a false statement regarding ameloblastoma from the
statements given below
(a) Slowly growing, locally invasive tumor
(b) Trabecular pattern is one of the histological subtypes
(c) Radiographically seen as well-defined, multilocular
radiolucency
(d) Predilection for occurring in posterior mandibular region

Answer 33

(b) Follicular and plexiform patterns are the most common
histological subtypes. Less common histopathological
patterns include the acanthomatous, granular cell,
desmoplastic, and basal cell types

Question 34

Which amongst the following radiographic appearances is most
likely to represent a conventional ameloblastoma?
(a) Ill-defined, radiolucency
(b) Well-defined unilocular radiopacity attached to root of tooth
(c) Well-defined, mixed radiopaque-radiolucent lesion in
anterior maxilla.
(d) “Soap bubble/Honeycomb” radiolucent defects with
scalloped margins

Answer 34

(d) Conventional ameloblastoma usually shows “soap bubble”
appearance when the radiolucent loculations are large
and as being “honeycombed” when the loculations are
small. Buccal and lingual cortical expansion is frequently
present. Resorption of the roots of teeth adjacent to the
tumor is common. In many cases, an unerupted tooth is
associated with the radiolucent defect. The margins of these
radiolucent lesions often show irregular scalloping.

Question 35

Which amongst the following is not a histological subtype of
unicystic ameloblastoma?
(a) Intramural (b) Intraluminal
(c) Luminal (d) Mural

Answer 35

(a) Three histopathological variants of unicystic ameloblastoma
are described. First type called luminal unicystic
ameloblastoma, is confined to the luminal surface of the
cyst. In the second variant called intraluminal, one or more
nodules of ameloblastoma project from the cystic lining into
the lumen of the cyst. In the third variant known as mural
unicystic ameloblastoma, the fibrous wall of the cyst is
infiltrated by typical follicular or plexiform ameloblastoma.

Question 36

_______ is the most common site for metastases of malignant
ameloblastoma.
(a) Vertebrae (b) Long bones
(c) Cervical lymph nodes (d) Lungs

Answer 36

(d) Metastases from ameloblastomas are most often found
in the lungs. Cervical lymph nodes are the second most
common site for metastasis of an ameloblastoma. Spread
to vertebrae, other bones and viscera has also occasionally
been confirmed.

Question 37

The histogenesis of clear cell odontogenic carcinoma is believed
to be
(a) Postfunctional ameloblasts
(b) Presecretory ameloblasts
(c) Stratum intermedium cells
(d) Stellate reticulum cell

Answer 37

(b) Histochemical and ultrastructural studies show that
the clear cells, which are the prominent feature of this
neoplasm, have similarities to glycogen rich pre-secretory
ameloblasts.

Question 37

Which of the following odontogenic tumors is also referred to as
adenoameloblastoma?
(a) Ameloblastic fibroma
(b) Ameloblastic fibroodontoma
(c) Odontoameloblastoma
(d) Adenomatoid odontogenic tumor

Answer 37

(d) The adenomatoid odontogenic tumor represents 3% to
7% of all odontogenic tumors. This lesion was previously
considered to be a variant of the ameloblastoma and was
designated as “adenoameloblastoma.” However, its clinical
features and biologic behavior indicate that it is a separate
entity.

Question 38

The follicular type of adenomatoid odontogenic tumor is
impossible to differentiate radiographically from
(a) Odontogenic keratocyst
(b) Dentigerous cyst
(c) Calcifying odontogenic cyst
(d) Ameloblastoma

Answer 38

(b) In many of the cases, the tumor appears as a well-defined,
unilocular radiolucency involving the crown of an
unerupted tooth, most often a canine. This type of follicular
adenomatoid odontogenic tumor may be impossible to
differentiate radiographically from the more common
dentigerous cyst

Question 39

Which amongst the following odontogenic tumors is considered
to be the least aggressive clinically?
(a) Conventional ameloblastoma
(b) Clear cell odontogenic carcinoma
(c) Ameloblastic fibrosarcoma
(d) Adenomatoid odontogenic tumor

Answer 39

(d) Some authorities feel that, given the slow growth and
circumscription of the lesion, it is best classified as a
hamartoma (developmental tumor-like swelling) rather
than a true neoplasm.

Question 40

The tumor cells of calcifying epithelial odontogenic tumor bear a
close histological resemblance to _________ cells of dental organ.
(a) External dental epithelium
(b) Stellate reticulum
(c) Stratum intermedium
(d) Internal dental epithelium

Answer 40

(c) The tumor cells bear a close morphologic resemblance to
the cells of the stratum intermedium of the enamel organ.
However, some investigators have recently suggested that
the tumor arises from dental lamina remnants based on its
anatomic distribution in the jaws.

Question 41

Which one of the following lesions is not associated with an
unerupted/impacted tooth?
(a) Conventional ameloblastoma
(b) Squamous odontogenic tumor
(c) Unicystic ameloblastoma
(d) Ameloblastic fibroma

Answer 41

(b) Squamous odontogenic tumor is a rare benign odontogenic
neoplasm. Most of these are usually located within bone,
although a few peripheral examples have been described.
This lesion was initially believed to represent an atypical
acanthomatous ameloblastoma or even a squamous cell
carcinoma. The squamous odontogenic tumor may arise
from neoplastic transformation of dental lamina rests or
the epithelial rests of Malassezia

Question 41

Areas of amorphous, eosinophilic, amyloid like extracellular
masses are typically seen in which of the following lesions?
(a) Squamous odontogenic tumor
(b) Unicystic ameloblastoma
(c) Calcifying epithelial odontogenic tumor
(d) Odontoma

Answer 41

(c) CEOT shows discrete islands, strands, or sheets of polyhedral
epithelial cells in a fibrous stroma along with large areas
of amorphous, eosinophilic, amyloid-like extracellular
material. Calcifications, which are a distinctive feature of
the tumor, develop within the amyloid like material and
form concentric rings (Liesegang ring calcifications).

Question 42

With which other odontogenic tumor can a squamous
odontogenic tumor be confused with histopathologically?
(a) Follicular ameloblastoma
(b) Acanthomatous ameloblastoma
(c) Compound odontoma
(d) Pindborg tumor

Answer 42

(b) Consist of varying shaped islands of bland appearing
squamous epithelium in a mature fibrous connective
tissue stroma. The peripheral cells of the epithelial
islands do not show the characteristic polarization seen
in ameloblastomas, thus helping in distinguishing this
neoplasm from ameloblastoma

Question 43

Unicystic ameloblastoma presenting as a well-circumscribed
radiolucency surrounding the crown of an unerupted/impacted
tooth is most likely to be diagnosed as
(a) Conventional ameloblastoma
(b) Unicystic ameloblastoma
(c) Squamous odontogenic tumor
(d) Dentigerous cyst

Answer 43

(d) All such cases will be diagnosed initially as a dentigerous
cyst. The surgical findings may also suggest that the lesion
in question is a cyst and the diagnosis of ameloblastoma is
made only after microscopic study of the specimen.

Question 44

Which amongst the following does not represent a hamartomatous
proliferation?
(a) Lymphangioma (b) Complex odontoma
(c) Ameloblastic fibroma (d) Compound odontoma

Answer 44

(c) The ameloblastic fibroma is considered to be a true mixed
tumor in which the epithelial and mesenchymal tissues
are both neoplastic, thereby being classified as a mixed
odontogenic tumor

Question 45

The ectodermal component of ameloblastic fibroma
characteristically proliferates in the form of
(a) Sheets
(b) Ducts
(c) Large islands
(d) Long narrow anastomosing cords

Answer 45

(d) The most common epithelial pattern consists of long, narrow
cords of odontogenic epithelium, often in an anastomosing
arrangement. These cords are usually only two cells in
thickness and are composed of cuboidal or columnar
cells.

Question 46

The mesenchymal component of ameloblastic fibroma closely
resembles
(a) Dental organ (b) Dental follicle
(c) Dental lamina (d) Dental papilla

Answer 46

(d) Microscopically, the tumor is composed of a cell rich
mesenchymal tissue resembling the primitive dental papilla admixed with proliferating odontogenic epithelium in the
form of discrete rests or islands. The mesenchymal portion
of the ameloblastic fibroma consists of plump stellate and
ovoid cells in a loose matrix which closely resembles the
developing dental papilla.

Question 47

______ is the only odontogenic tumor amongst the following
which does not usually occur in younger individuals.
(a) Odontoameloblastoma
(b) Ameloblastic fibro-odontoma
(c) Granular cell odontogenic tumor
(d) Odontoma

Answer 47

(c) Patients with granular cell odontogenic tumors have all
been adults at the time of diagnosis, with over half being
older than 40 years of age. The tumor occurs primarily in the
mandible and most often in the premolar and molar region.
Some lesions are completely asymptomatic; others present
as a painless, localized expansion of the affected area.

Question 48

Which amongst the following lesions occurs more frequently in
anterior maxilla?
(a) Adenomatoid odontogenic tumor
(b) Unicystic ameloblastoma
(c) Granular cell odontogenic tumor
(d) Cementoblastoma

Answer 48

(a) AOT occurs most frequently in the anterior maxilla region
usually in association with an impacted or unerupted tooth.

Question 49

Which is the least likely lesion to be considered in the differential
diagnosis of a hard, bony swelling in posterior mandibular region
which appears radiographically as a well defined multilocular
radiolucency in association with an impacted mandibular 3rd
molar?
(a) Adenomatoid odontogenic tumor
(b) Ameloblastoma
(c) Ameloblastic fibroma
(d) Calcifying epithelial odontogenic tumor

Answer 49

(a) AOT is the only lesion amongst the given lesions, that most
commonly occurs in anterior maxillary region, usually
in association with impacted maxillary canine. Also,
radiologically, AOT is unilocular compared to other given
lesions.

Question 50

In which of the following tumors, the epithelial component
is neoplastic while its mesenchymal component remains
unaffected?
(a) Odontogenic myxoma
(b) Compound odontoma
(c) Squamous odontogenic tumor
(d) Ameloblastic fibrosarcoma

Answer 50

(c) All other given lesions are mixed odontogenic tumors, i.e.
derived from both epithelium and mesenchyme, while the
squamous odontogenic tumor is an odontogenic tumor
derived from odontogenic epithelium only.

Question 51

Which odontogenic tumor histologically shows ameloblastomalike
features along with those of a compound/complex
odontoma?
(a) Ameloblastic fibroma
(b) Odontoameloblastoma
(c) Ameloblastic fibro-odontoma
(d) Ameloblastic fibrosarcoma

Answer 51

(b) Odontoameloblastoma is an extremely rare odontogenic
tumor that contains an ameloblastomatous component
and odontoma-like elements. This tumor was previously
called “ameloblastic odontoma” and was confused with the
more common lesion currently designated as ameloblastic
fibro-odontoma

Question 52

Radiographic features of multiple teeth-like structures
surrounded by a radiolucent zone are diagnostic of
(a) Complex odontoma
(b) Odontoameloblastoma
(c) Ameloblastic fibro-odontoma
(d) Compound odontoma

Answer 52

(d) Odontomas are the most common odontogenic tumors.
Fully developed odontomas consist chiefly of enamel and
dentin with variable amounts of pulp and cementum.
They are further subdivided into compound and complex
types. Compound odontoma is composed of multiple,
small tooth-like structures. Complex odontoma consists
of a conglomerate mass of enamel and dentin which bears no anatomic resemblance to a tooth. Radiographically, the
compound odontoma appears as a collection of tooth-like
structures of varying size and shape surrounded by a narrow
radiolucent zone.

Question 53

A cellular fibroblastic lesion containing occasional inactive
odontogenic epithelial rests, occurring in posterior mandibular
region is suggestive of
(a) Central odontogenic fibroma
(b) Conventional ameloblastoma
(c) Pindborg tumor
(d) Clear cell odontogenic carcinoma

Answer 53

(a) In ameloblastic fibroma, the epithelial component
proliferates in the form of long anastomosing cords,
rosettes or finger-like strands, while desmoplastic fibroma
does not contain any epithelial islands and the peripheral
odontogenic fibroma occurs in the soft tissues.

Question 54

Out of the following lesions which is the only true neoplasm of
cementoblasts?
(a) Familial gigantiform cementoma
(b) Cemento-osseous dysplasia
(c) Cemento-ossifying fibroma
(d) Cementoblastoma

Answer 54

(d) Odontogenic fibroma is a rare, controversial lesion,
occurring in patients of ages between 4–80 years with a 2.2
to 1 female predilection. About 45 percent of cases usually
occur in maxilla, anterior to the first molar. In mandible,
however, about half of the tumors are located posterior
to the first molar. They are microscopically composed of
stellate fibroblasts, often arranged in a whorled pattern with
fine collagen fibrils and considerable ground substance.
Small foci of odontogenic epithelial rests may or may not
be present.

Question 55

A radiopaque mass that is fused to one or more tooth roots and
surrounded by a thin radiolucent rim is highly suggestive of
(a) Cementoblastoma (b) Pindborg tumor
(c) Fibrous dysplasia (d) Odontogenic myxoma

Answer 55

(a) Cementoblastoma is an odontogenic neoplasm of
cementoblasts, and is believed to represent the only true
neoplasm of cementum. More than 75 percent tumors
arise in the mandible with 90 percent arising in the
molar-premolar region. Pain and swelling are present
in approximately 2/3rd of patients. Radiographically, it
appears as a radiopaque mass fused to one or more tooth
roots and surrounded by a thin radiolucent rim. The outline
of the root or roots of the involved tooth is usually obscured
as a result of root resorption.

Question 56

Dense fibrous connective tissue stroma which appears more
prominent than the neoplastic ameloblastic epithelium is seen
in which subtype of ameloblastoma?
(a) Follicular (b) Plexiform
(c) Acanthomatous (d) Desmoplastic

Answer 56

(d) This type of ameloblastoma contains small islands and
cords of odontogenic epithelium in a densely collagenized
stroma. Peripheral columnar ameloblast like cells are
inconspicuous around the epithelial islands.