Mutations in the genes encoding fibrillin, an extracellular matrix protein involved in providing elastic properties to the connective tissues, may result in specific craniofacial and oral anomalies. A number of craniofacial (retrognathia, dolichocephaly, high palate) and dental (root deformity, pulp calcification) manifestations are considered pathognomic for the Marfan syndrome (MFS), a condition caused by congenital fibrillin-1 deficiency. Reports on similar features in congenital contractural arachnodactyly (CCA), caused by fibrillin-2 deficiency, support the hypothesis that fibrillin deficiency might result in a number of morphological anomalies by influencing tissue interaction during growth and development. Hence, clinical manifestations can be related to specific aspects of fibrillin deficiency pathogenesis, and may be adopted as diagnostic tools in the outlook for affected individuals.