Odontogenic Cysts ( Inflammatory)

Question 1

DEFINITION OF CYST

Answer 1

Cyst may be simply defined as a pathological cavity
containing fluid or semifluid or even tissue debris

Question 2

Sources of Odontogenic Epithelium

Answer 2

1. Reduced E. epithelium.
2. Epithelial rests of Malessez.
3. Remnants of dental Lamina. (Serre’s).
4. Basal layer of oral alveolar epithelium.
5. A tooth germ.

Question 3

Names of radicular cyst

Answer 3

Radicular Or Dentoalveolar Cyst
(Apical Cyst. Periapical Cyst)

Question 4

Mechanism of cyst formation
( Theories of cyst formation or cystification )

Answer 4

1- Nutritional Deficiency theory

2- Merging of Epithelial Strand theory

3-Abscess theory

Question 5

Clinical Features of radicular cyst

Answer 5

Asymptomatic. discovered
incidentally.
As they enlarge, they cause slowly
progressive painless swellings
- Age :3 to 6 decades .
- More in male.
- Maxilla more than mandible
in the following orders:
Maxillary anterior ,
Maxillary posterior ,
Mandibular posterior , then anterior

Question 6

Radiographic Features

Answer 6

• Similar to periapical
  granuloma.
• Well defined round or
  oval radiolucency with
  radio opaque margin
  continous with lamina
  dura.
• The adjacent teeth can be
  displaced but rarely
  resorbed.

Question 7

Histopathologic Features

Answer 7

Epithelial lining is Non keratinized stratified squamous
epithelium.
- The epithelial lining may be only a few cells thick, or it
may be thick up to 20 or more cell layers

Rushton bodie
Curvilinear, eosinophilic, hyaline (within ep)
CT. capsule:
- Connective tissue is composed of collagen fibers,
fibroblasts and capillaries
- Focal or diffuse acute and chronic inflammatory cell
infiltration
- Cholesterol clefts be present.
- Multinucleated foreign-body giant cells may be seen close
to cholesterol clefts
- lipid filled macrophages (foam cells )

Question 8

Residual cyst etiology

Answer 8

They are radicular cysts that have remained in
the jaw and failed to resolve following
extraction of the involved tooth.

Question 9

Clinical Features

Answer 9

Usually asymptomatic and found on routine
radiographic examinations. It is found in tooth bearing area

Question 10

Paradental Cyst (lateral)
Etiology and site

Answer 10

• Develops on the lateral surface of a tooth root.
• Result of inflammation of the gingiva over an
  erupting molar.
• Associated with partially impacted 3rd molars .

Question 11

Radiographic Features

Answer 11

It presents as a well-defined radiolucency with thin
radioopaque margins ( occlusal film showing tilting of the roots of envolved tooth)

Question 12

-Buccal Bifurcation cyst etiology

Answer 12

• Uncommon.
• Develops on the buccal aspect over the
  furcation area of the mandibular first
  permanent molar.
• From buccal pocket, or tooth with ectopic
  enamel

Question 13

Clinical features :

Answer 13

Usually in children
- Tenderness in the buccal aspect of the mand.1st
molar.
- Swelling
- Buccal pocket, foul odour

Question 14

Radiographic features:

Answer 14

• It appears as a well circumscribed unilocular area
involving the buccal furcation area