Rare diseases

BACKGROUND: It is estimated that 30 million people in the United States have a rare disease, and few of these conditions have available cures. The diversity of rare disease etiologies and phenotypes has hindered both diagnostics and treatment approaches. Many rare diseases are caused by pathogenic genetic variations and involve the craniofacial structures and function. Dental care providers are called on to serve the population with rare diseases and support their desire for optimal health. To address these oral health care challenges, JADA is presenting a special issue on rare diseases through a series of articles. These reviews will address some of the more common rare diseases and those that share features such as involvement of the dentition, skeleton, immune system, skin, or facial clefts. TYPES OF STUDIES REVIEWED: The authors searched the 5 major databases, including PubMed, Google Scholar, Web of Science, Embase, and Ovid MEDLINE, for articles pertaining to rare diseases and disorders affecting oral health and oral health care. The authors conducted an exhaustive search of the literature from 1990 through March 30, 2026, for articles on rare diseases, with a specific focus on oral health care. RESULTS: There is no existing reliable classification that groups all of these complex syndromes into clinically identifiable clusters. This special issue may be the first of its kind in which the authors attempt to format a meaningful classification to group these entities of similar etiopathogenesis and phenotype. CONCLUSIONS AND PRACTICAL IMPLICATIONS: The medical and dental management of rare disorders often requires teams of specialists and advocates to address the developmental, structural, functional, psychosocial, and economic aspects that can confront affected patients.