title: Symmetric multiquadrant isolated dentin dysplasia (SMIDD), a unique presentation mimicking dentin dysplasia type 1b.
abstract: Dentin dysplasia (DD) is a rare developmental dentin disorder that causes root malformation. It is divided into radicular DD type 1 (DD-1) and coronal DD type 2 (DD-2). Recently, a new entity causing localized root malformation of permanent first molars that resembles DD-1b has been described as molar-incisor malformation (MIM). We report and compare 4 new cases that exhibit similar clinical, histologic, and radiographic features to the new entity, MIM. We believe MIM and our 4 cases to be the same entity, which is nonhereditary and, because of the isolated but bilaterally symmetric pattern of involvement, may be caused by a short-duration environmental insult that disrupts normal development/function of Hertwig's epithelial root sheath. We propose the name symmetrical multiquadrant isolated dentin dysplasia as the most appropriate descriptive designation for this unusual but highly distinctive anomaly.
authors.affiliation: Texas A&M University College of Dentistry, Dallas, TX, USA. Electronic address: Hiba_qari@yahoo.com.
authors.forename: Hiba
authors.initials: H
authors.lastname: Qari
authors.affiliation: Texas A&M University College of Dentistry, Dallas, TX, USA.
authors.forename: Harvey
authors.initials: H
authors.lastname: Kessler
authors.affiliation: University of Nebraska Medical Center College of Dentistry, Lincoln, NE, USA.
authors.forename: Nagamani
authors.initials: N
authors.lastname: Narayana
authors.affiliation: University of Nebraska Medical Center College of Dentistry, Lincoln, NE, USA.
authors.forename: Sundaralingam
authors.initials: S
authors.lastname: Premaraj
mesh_terms: D000293:Adolescent; D002648:Child; D003805:Dentin Dysplasia / Q000145:classification* / Q000000981:diagnostic imaging; D005260:Female; D006801:Humans; D008297:Male