There are two main types: compound and complex. * A compound<unk>  consists of the four separate dental tissues (enamel, dentine, cementum and pulp) embedded in fibrous connective tissue and surrounded by a fibrous capsule. It may present a lobulated appearance where there is no definitive demarcation of separate tissues between the individual "toothlets" (or denticles). Compound<unk> s are usually found in the anterior maxilla and are less than 20mm in diameter. * The complex type is unrecognizable as dental hard and soft tissues, usually presenting as a radioopaque area with varying densities indicating presence of enamel. It generally appears in the posterior mandible and can grow to be several centimetres in size. In addition to the above forms, the dilated<unk>  is an infrequent developmental alteration that appears in any area of the dental arches and can affect deciduous, permanent and supernumerary teeth. Dens invaginatus is a developmental anomaly resulting from invagination of a portion of crown forming within the enamel organ during odontogenesis. The most extreme form of dens invaginatus is known as a dilated<unk> . There are two types of lesions which are regarded as complex<unk> s with a prominent soft tissue component resembling ameloblastic fibroma. With similar presentation and treatment outcomes to complex<unk> s. These lesions were poorly defined previously and were removed as separate entities from the WHO Classification of Head and Neck Tumors (2017). They are now regarded as developing<unk> s as histologically there are no differences. * Ameloblastic fibrodentinoma with only dentine present * Ameloblastic fibro-odontoma with both enamel and dentine present
Odontoma
Odontogenic cyst
Paradental cyst
Dentigerous cyst
Gingival cyst
Colloid cyst
Choristoma
Thyroglossal cyst