Cysts of Oral cavity

• Cyst is a cavity occurring in whether hard or soft tissues with a liquid or semi-solid or air only
• It is surrounded by a definitive connective tissue wall on capsule and has an unusual epithelial lining
• Most common
• Periapical cyst:
• Primordial cyst (keratocytes)
• Dentigenous cyst

Periapical cyst

• It is an epithelium lined sac containing ;liquid or semi-solid inflammatory exudates and necrotic products
• It originates from dental granuloma of infected periapical tissues

Key features:

• Forms in bone in relation to root of non-vital tooth
• Arise by epithelium proliferation on an apical granuloma
• Usually asymptomatic unless injected

Diagnosis

• Radiographic appearance of non-vital tooth
• Histological appearances

Treatment:

Enucleation: Do not recur after complete enucleation.

OR

Marsupialization: Indications of marsupialization:

• The cyst has eroded into the mandible, and by its enucleation we risk a discontinuation in mandible
• The cyst is large
• Certain vital structures are involved by the cyst.

In all these cases, we first inject into the cyst and drain the content. Then we instil antibiotics and wait until its size regresses. Once it gets small, we enucleate it. This is called marsupialization.

Primordial cysts

• It is formed due to regression of satellite reticulum in the enamel organ which takes place before any calcified teeth structure is formed
• It contains keratin tissue
• Usually multi-locular
• From intraosseoulsy, most frequently in post alveolar ridge is angle of mandible;
• Frequently recur after enucleation
• Do not respond to marsupialization
• Radiological appearance usually multi-locular frequently mononuclear
• Histologically: epithelial lining of uniform thickness’ and attached weakly to the fibrous wall