Definition of Cyst• A cyst is an epithelial lined pathologic cavity occuring either in hard or soft tissue and may contain a fluid or semi-fluid material (True Cyst).• Some cysts may not be epithelial- lined & therefore are not true cysts (Pseudocysts).
Cysts Classification Non- Pseudo- Soft TissueOdontogenic cyst Odontogenic Cysts Naso- Dermoid, Ep periodontal Traumatic Palatine idermoid Bone C. Tract C. Dentigerous Thyro- glossal tract Aneurysmal C. Fissural Bone C. Primordial Benign lympho- Static KCOC, epithelial Bone C. Gorlin’s cyst Mucous Retention ,Extravasat.
1- Odontogenic Cysts• Def.: these arise from epithelial remnants associated with the development of teeth odontogenic epithelium.• Site: Affect the tooth bearing region of the jaw.• Origin of epithelium:- Enamel organ.- Reduced enamel epithelium.- Epithelial rests of Malassez.- Epithelial rests of Serres (dental lamina remnants).
Periodontal CystsInflammatory Developmental Apical Lateral Lateral Gingival C. adults Gingival C. Residual newborn
Periodontal Inflammatory Cysts• Cause: it results from inflammatory hyperplasia of the epithelial rests of Malassez in the periodontal ligament following death of the pulp.• Types according to its location:- Apical or periapical or radicular : related to root apex.- Lateral: related to lateral root surface & accessory root canal.- Residual: left after extraction in edentulous area of jaw.
1-Inflammatory Periodontal Apical (Periapical, Radicular) Cyst Periapical Inflammatory ↑↑epith. granuloma proliferation mass DegenerationEpith. Lined Separation +cavity filled of cells in liquefication with fluid the central of central formed portion cells Apicalperiodont al cyst
Mechanism of Cyst Enlargement Tissue ↑osmoticbreakdown pressure Fuid Osteoclastictransport to bonecystic cavity resorption Enlarging the bony cavity
Clinical Features of Inflamm. Apical Cyst• Age: adult (3rd -6th )decade.• Sex: male ˃ female.• Site: maxilla ( anterior area).• Symptoms:- No infection → painless.- Infection occurs → painful.- Rounded swelling• Signs:-non-vital tooth, eggshell crackling sensation under pressure then fluctant swelling.
X-ray of Inflammatory Apical Cyst•Shape: Round orovoid• Margin: Well-defined•Radiolucency.•Size : (5mm –several cm).•Related Tooth: mayhas a large cariouscavity or large filling.
The Epithlium Lining of Apical Cyst• Stratified squamous epith. Acanthosis (20 cell layer).• Newly formed cyst:• -Hyperplasic, forming rings around inflammatory cells.• Fully formed cyst:• - Regular, flattened with few inflammatory cells.
Lumen Content or Fluid of Apical Cyst•The lumen containsfluid which stainseosinophilic.•Sometimes containscholesterol in greatamount.•Chemically: containsalbumin, globulin,cholesterol &nucleoproteins.
Treatment of Inflammatory Apical Cyst • Enucleation. Small • Apicectomy. • Enucleation.Medium • Extraction of tooth. • Marsupilization to avoid imp. Structures e.g. Large antrum & inf. Alveolar nerve.
2- Inflammatory Lateral Periodontal Cyst• Less common ˃periapical.•Site: at the side ofthe root of a pulplesstooth.•Cause: a result ofopening of a lateralroot canal & irritationof periodontal tissue.
3- Inflammatory Residual Periodontal Cyst•Cause:-The pulpless tooth fromwhich a periapical cystmay persist in the jawbone.•Complication:-Interfering with thefittness of dentures. -Enlarge to the extent ofweakning of the jaw. -Jaw fructure
Developmental Lateral Periodontal Cyst•Def.: a non-inflammatorydevelopmental cyst whichoccurs adjacent or lateralto the root of vital tooth.•Cause: proliferation ofrests of odontogenicepithelium at lateral sideof adjacent vital tooth.
Clinical Features of Developmental Lateral Periodontal Cyst• Age: any age.• Sex: male ˃female.• Site: 2 543• Signs : may cause a slight bulge although the overlying mucosa is normal.• Symptoms:- Asymptomatic- Vital tooth.
X-ray of Developmental Lateral Periodontal Cyst•Small , rarely over1 cm.•Radiolucent area.•May or may notwell circumscribedwith an opaquemargin.
Histology of Developmental Lateral Periodontal Cyst•C.T wall: may haveinflammatory cell ifthe cys get infected.•Epith. Lining:-Stratified squamous .-Thin( 1-2)layers.-Epith. Cells with clearcytoplasm& smalldeeply stained nuclei.-Parakeratin ororthokeratin.
Developmental Gingival Cysts Of The New Born Of Adulthood (Bohn’s Nodules)• Origin: from dental • Origin: from dental lamina remnants in the lamina remnants which proliferate to form small ST between the oral cyst. epith.& periosteum.• Shape: • Shape: multiple white wellcircumscribed nodules. swelling of the gingiva.• Size: small ˃1cm. • Size: ˃ few mm. • Site: on the alveolar• Site: free & attached ridge of new born infant gingiva or papilla(adult).
Developmental Gingival Cysts Of The New Born Of Adulthood (Bohn’s Nodules)
Developmental Gingival Cysts Of Adulthood Of The New Born• X-ray: (-ve) soft tissue & • X-ray: (-ve) soft tissue. vital tooth. • Histology:• Histology: - Thin epith.- Thin epith., flattened st. - The lumen filled with sq.cells. desqumated keratin.- Non- keratinized. • Treatment:• Treatment: - No treatment &- No treatment. discharge their content into the oral cavity.
Developmental Gingival CystsOf Adulthood Of The New Born