TOOTH AGENESIS IN DOWN-SYNDROME

We studied the frequency and pattern of tooth agenesis in a Danish pop ulation with Down syndrome, trisomy 21 (46 females and 54 males). The control group consisted of a normal Danish population (2424 females an d 2431 males) [Rolling, 1980: Scand J Dent Res 88:365-369; Ravn and Ni elsen, 1973: Tandlaaegebladet 77:12-22], We found that individuals wit h Down syndrome have an occurrence of agenesis that is some 10 times g reater that in the general population with a higher frequency in males than in females. Agenesis occurred more frequently in the mandible th an in the maxilla and most often on the left side. The highly signific ant differences were primarily found in the occurrence of agenesis of the mandibular central incisors, followed by the maxillary lateral inc isors and second premolars and the mandibular second premolars. The ma in components in the pattern of agenesis observed in Down syndrome are supposed to be related to the peripheral nervous system and abnormal cartilagenous tissue. The present study on Down syndrome suggests that the dentition, with its many different anomalies, from agenesis to ma lformation, can be used as an indicator in evaluating different aspect s in the patheogenetic of aneuploidy conditions. (C) 1995 Wiley-Liss, Inc.