Odontoma: A mixed tumor of odontogenic origin, in which both the epithelial and mesenchymal cells exhibit complete differentiation, resulting in the formation of tooth structures. (Jablonski, Illustrated Dictionary of Dentistry, 1982)Mandibular Neoplasms: Tumors or cancer of the MANDIBLE.Maxillary Neoplasms: Cancer or tumors of the MAXILLA or upper jaw.Odontogenic Cyst, Calcifying: A mixed radiolucent-radiopaque lesion of the jaws with features of both a cyst and a solid neoplasm. It is characterized microscopically by an epithelial lining showing a palisaded layer of columnar basal cells, presence of ghost cell keratinization, dentinoid, and calcification. (Stedman, 25th ed)Palatal Neoplasms: Tumors or cancer of the PALATE, including those of the hard palate, soft palate and UVULA.Dental Cementum: The bonelike rigid connective tissue covering the root of a tooth from the cementoenamel junction to the apex and lining the apex of the root canal, also assisting in tooth support by serving as attachment structures for the periodontal ligament. (Jablonski, Dictionary of Dentistry, 1992)Tooth, Impacted: A tooth that is prevented from erupting by a physical barrier, usually other teeth. Impaction may also result from orientation of the tooth in an other than vertical position in the periodontal structures.Enamel Organ: Epithelial cells surrounding the dental papilla and differentiated into three layers: the inner enamel epithelium, consisting of ameloblasts which eventually form the enamel, and the enamel pulp and external enamel epithelium, both of which atrophy and disappear before and upon eruption of the tooth, respectively.Odontogenic Tumors: Neoplasms produced from tooth-forming tissues.Tooth Abnormalities: Congenital absence of or defects in structures of the teeth.