10 - Odontogenic Cysts and Tumors

Abstract

Odontogenic cysts and tumors represent a surprisingly diverse group of lesions of the jaws and overlying soft tissues. In general, odontogenic cysts may be developmental or inflammatory in origin. Developmental odontogenic cysts include the following: the dentigerous cyst, eruption cyst, odontogenic keratocyst, orthokeratinized odontogenic cyst, gingival cyst of the newborn, gingival cyst of the adult, lateral periodontal cyst, glandular odontogenic cyst, and calcifying odontogenic cyst. Inflammatory odontogenic cysts include periapical cysts and residual periapical cysts. In general, odontogenic cysts are benign, although malignant transformation is possible. Benign odontogenic tumors may be subclassified as follows: (1) epithelial (including ameloblastoma, calcifying epithelial odontogenic tumor, squamous odontogenic tumor, and adenomatoid odontogenic tumor); (2) mixed epithelial and mesenchymal (including ameloblastic fibroma, ameloblastic fibroodontoma, odontoma, primordial odontogenic tumor, odontoameloblastoma, and dentinogenic ghost cell tumor); and (3) mesenchymal (including central odontogenic fibroma, peripheral odontogenic fibroma, granular cell odontogenic tumor, and odontogenic myxoma). Furthermore, there are several types of malignant odontogenic tumors, including metastasizing ameloblastoma, ameloblastic carcinoma, primary intraosseous squamous cell carcinoma, clear cell odontogenic carcinoma, ghost cell odontogenic carcinoma, intraosseous mucoepidermoid carcinoma, ameloblastic fibrosarcoma, and odontogenic carcinosarcoma. The diversity of odontogenic cysts and tumors can be difficult to understand without basic knowledge of the process of odontogenesis. Hence, we begin with a review of the histology and embryology of tooth formation. In addition, clinical correlation is often essential for accurate diagnosis. Therefore we discuss the clinical features, as well as pathologic features, differential diagnosis, treatment, and prognosis for each entity.