It is the most common chromosomal aberration, with the highest survival rate of all such disorders. Its incidence is 1.5 per 1000 live births, increasing markedly with advanced maternal age. Population surveys in institutions for the mentally retarded reveal that approximately 10% of such institutionalized patients have Down syndrome.
Most frequent chromosomal abnormality in Down syndrome is trisomy 21(47 XX females; 47 XY males)
- About 4% have translocation of chromosome 21
- Approximately 1% of patients with Down syndrome are mosaics, which means there is a population of cells with both normal and trisomic chromosome numbers. (a mixture of 46 and 47 chromosome cells)
Dental management and treatment
- Many children with Down syndrome are affectionate and cooperative, and dental procedures can be provided without compromise if the dentist works at a slightly slower pace.
- Emphasis should be on preventive dental care with frequent follow up visits.
- Light sedation and immobilization may be indicated in those children who are moderately apprehensive.
- Severely resistive patients may require GA.
- Guidelines established by American Heart Association for SBE coverage should be followed in cases of presence of congenital heart diseases.