Trichodental syndrome is a rare autosomal dominant ectodermal dysplasia. Hair and dental anomalies have been found in different combinations in most affected persons in three families. The features of trichodental syndrome were observed in a young female in which sparse, fine, lustreless and slow growing hairs were associated with bigeminismus of inferior lateral incisors. Ultrastructural hair analysis showed consistent variation in contour of the shaft and reduced to absent cuticular scale. Distinguishing features in this patient were microcephaly and mild mental retardation.