Benign Odontogenic Tumors in Radiology PDF

# Benign Odontogenic Tumors ### Epithelial Origin - **AmeloBlastoma:** - Most common odontogenic tumor - Major difference between tumors and cyst is that tumors cause expansion. It is an aggressive neoplasm but with benign growth characteristics. - Ameloblastoma may be divided into unicystic/Loc...

# Benign Odontogenic Tumors ### Epithelial Origin - **AmeloBlastoma:** - Most common odontogenic tumor - Major difference between tumors and cyst is that tumors cause expansion. It is an aggressive neoplasm but with benign growth characteristics. - Ameloblastoma may be divided into unicystic/Locular type and multicystic type. - Most common in men, variety in age (20-40). - **Imaging Features:** - Location: Most cases in the molar area, and if it's in the maxilla it extends into the maxillary sinus. - Periphery: Usually well-defined or corticated. - Internal structure: Unilocular or multilocular radiolucent with curved bony septa giving soap-bubble or honeycomb appearance. - **Effect on surrounding structure:** - It causes: - Extensive root resorption. - Tooth displacement. - Thinning of the adjacent cortical bone leaving "egg-shell" of bone. - Expansion of the mandible and ramus. - Displacement of the inf alveolar canal. - Paresthesia of the lip. ### Differential Diagnosis - **If uni cystic** -> Dentigerous cyst. - **If multi cystic** -> - KOT marked "*المرقة إنه مش يبعد*" in a mesio-distal direction expansion. - It expands in a mesio-distal direction. - Odontogenic myxoma. - The presence of one or two thin straight septa indicates myxoma. - **Even if one**: - It occurs at the lower anterior area and in a younger age and have granular septa. - **Ameloplastic fibroma**: Ill-defined septa. - **Hemangioma:** In young age. - **Anurysmal cyst**. - **Ossifying fibroma**: It has wide granular ill-defined septa. ## Calcifing epithelial odontogenic tumor (CEOT) - Pindborg tumor - Less aggressive than ameloblastoma. - Occurs in old age and causes expansion. - **Imaging Features:** - Location: Most cases in posterior mandibular area with unerupted tooth. - Periphery: Well-defined corticated. - Internal structure: It may appear unilocular or multilocular, with numerous scattered calcification foci related to the crown (peri-coronal). ## Effect on surrounding structures: - Displacement of teeth or prevent it's eruption and expansion of the jaw. ### Differential diagnosis: - **Adenomatoid odontogenic tumor (AOT)**, in young age and anterior. - **Calcifing cystic odontogenic tumor (CCOT)**. - **Ameloblastic fibro-odontoma**, in young age. ## Mixed odontogenic tumors: - **Odontoma (odontogenic hamartoma)**: - Most common odontogenic tumor. - Interfere with the eruption of permanent teeth and causes delayed eruption. - Most common in 2nd decade of age and in children. - **Imaging features:** - Location: Compound odontoma most commonly found in anterior maxilla with an impacted canine. Complex odontomas in posterior mandibular region. - Periphery: Well-defined corticated. - Internal structure: Compound tooth-like radiopaque structure with a soft tissue capsule. - **Effect on surrounding structures** - Complex, irregular radiopaque mass with a soft tissue capsule. - Interfere with the normal eruption of teeth. - May cause expansion of jaw in complex odontomas. ### Differential diagnosis: - **PCD (Periapical Cemento dysplasia)**: multiple and periapical to teeth, less prominent soft tissue capsule. - **Cemento-ossifying fibroma**: Has uneven sclerotic border but odontomas have corticated borders and in younger age. - **Amelolastic fibroma**: - Occurs in young age (5-20 years). - Most common symptom is swelling or occlusal pain. - **Imaging features:** - Location: Posterior mandibular region and may extend into the ramus. - A common location is near the crest of alveolar process or in a follicular relationship of an unerupted tooth. - **Periphery:** Well-defined corticated. - **Internal structure:** More commonly unilocular radiolucency, but maybe multilocular. ## Effect on surrounding structure: - Expansion or displacement in apical direction or prevent eruption of teeth. ### Differential diagnosis: - **Amelo blastoma**, in younger age. - **Cameloblastic fibroma**, related to the follicular space. - **Dentigerous Cyst**, in older age. - **Odontogenic Myxoma**. - **Giant cell granuloma**, in older age. ## Ameloblastic Fibro-Odontoma - Usually appears with a missing tooth or unerupted tooth. - Same age as odontomas. - **Imaging features:** - Location: The epicenter is usually in the posterior mandibular region and the epicenter is usually occlusal to a developing tooth. - Periphery: Well-defined corticated. - Internal Structure: Mixed lesion. - **Differential diagnosis:** - Odontoma. - AoT. - CEOT. - CCOT. ## Adenomatoid Odontogenic Tumor (AOT) - Most common in females in 2nd decade of life. - **Effect on surrounding structures:** - Gradually enlarging painless swelling, often associated with a missing tooth (impacted canine). - **Imaging features:** - Location: Mostly in anterior maxilla, related have a follicular relationship with an impacted tooth. - Periphery: Well-defined corticated. - Internal structure: Mixed lesion with radio opaque foci in most cases (small pebbles). - **Effect on surrounding structures:** - Displacement of adjacent teeth. - The attachment at CEJ. - **Differential Diagnosis:** - Follicular cyst, dentigerous cyst. - KOT. - CEOT, in posterior mandible. ## Mesenchymal tumors - **Odontogenic myxoma:** - Not encapsulated have high cubrance rate and aggressive. - **Imaging features:** - Location: Posterior mandible, often ill defined in the maxilla. - Periphery: Well-defined, but most often ill-defined in the maxilla. - Internal structure: Unilocular or multilocular, with straight fine septa (tennis racket like or step ladder-like). - **Effect on surrounding structures:** - Expansion or displacement in apical direction or prevent eruption of teeth. - Displacement and looseness of teeth, frequently scallops between the roots of teeth, doesn't cause resorption. - Amelo blastoma rarely cause resorption. - **Differential diagnosis:** - Amelo blastoma. - Central giant cell granuloma. - Central hemangioma. ## Cemento blastoma (true cementoma) - In young age, solitary, more vital, common in males. - Painfull and tooth related. - **Imaging features:** - Location: Most common in the mandible, related to the root of the first molar. - Periphery: Well defined radioopacity with a corticated border. - Internal structure: Mixed lesion with a radiolucent band then radiopaque lesion (3 stages). - **Effect:** If the root is apparent, it causes external resorption of the root. - **Differential diagnosis:** - PCD. - Post mandible, multifocal, not painful, less prominent soft tissue capsule. - Enostosis. - Odontoma. - Condensing ostitis. - Tori. ## Central odontogenic fibroma - Clinical features: More common in females. - An unusual feature of some maxillary cases is that it causes depression or cleft in palate. - **Imaging features:** - Location: Posterior mandible. - Periphery: Well defined. - Internal structure: Most lesions are unilocular, small lesions are usually multilocular. - **Effect on surrounding structures:** - Expansion with thinning of cortex or can grow along with a minimum. - Tooth displacement and root resorption. - **Differential diagnosis:** - Desmoplastic fibroma. - Odontogenic myxoma.