title: Clinical and radiographic findings and usefulness of computed tomographic assessment in two children with regional odontodysplasia.
abstract: Regional odontodysplasia is a rare, severe, and nonhereditary developmental disorder in tooth formation and involves epithelial and mesenchymal-derived dental tissue. On radiographs, affected teeth have an abnormal morphology, a hypoplastic crown, and only a faint outline of hard tissue, a condition termed "ghost teeth." We report clinical and radiographic findings from two children with regional odontodysplasia. Using computed tomography (CT), we calculated attenuation coefficients (i.e., Hounsfield units) for affected teeth and assessed the condition of dental follicles. To measure density, regions of interest were delimited and CT values were calculated. In our two patients, the CT values for enamel were lower in affected teeth than in sound teeth, while CT values for dentin were similar for affected and sound teeth. The average CT value for dental follicles in affected teeth was about 65 to 120, which suggests that dense fibrous connective tissues or hard tissue-like structures might be present in dental follicles. Analysis of CT values may be quite useful in the diagnosis and treatment of regional odontodysplasia.
authors.affiliation: Division of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Junko
authors.initials: J
authors.lastname: Matsuyama
authors.affiliation: Division of Oral and Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Ray
authors.initials: R
authors.lastname: Tanaka
authors.affiliation: Takarazuka Sanda Hospital, 2-22-10 Nishiyama, Sanda, Hyogo, 669-1537, Japan.
authors.forename: Futabako
authors.initials: F
authors.lastname: Iizawa
authors.affiliation: Division of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Tomiko
authors.initials: T
authors.lastname: Sano
authors.affiliation: Division of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Shoko
authors.initials: S
authors.lastname: Kinoshita-Kawano
authors.affiliation: Division of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Hayashi-Sakai
authors.affiliation: Division of Pediatric Dentistry, Graduate School of Medical and Dental Sciences, Niigata University, 2-5274 Gakkocho-dori, Chuo-ku, Niigata 951-8514, Japan.
authors.forename: Tomoe
authors.initials: T
authors.lastname: Mitomi