Direct evaluation of salivary antioxidant properties in patients with down syndrome for assessment to periodontal disease and premature aging

To evaluate oxidative stress involved in Down syndrome periodontal disease and pathological premature aging, reactive oxygen species (ROS) such as superoxide (O₂•-) and hydroxyl radical (HO•) in human saliva were measured using electron spin resonance (ESR) spectroscopy. The groups consisted of 20 subjects in the Down syndrome (DS) child (DsC) group (mean age 11.3 ± 4.2 years), 24 subjects in the normal(N) child (NC) group (mean age 8.5 ± 2.0 years), 31 subjects in the DS-adults (DsA) group (mean age 48.9 ± 6.5 years), and 24 subjects in the N-adults (NA) group (mean age 47.1 ± 4.9 years). Comparing DS and N groups, gingivitis index (GI), pocket depth (PD) were higher in group A than in group C depending on age. The salivary O₂•- scavenging rate measured by ESR spectroscopy was lower in DS group, and the salivary antioxidant properties such as both O₂•- and HO• scavenging rate of DS and N groups, whose GI and PD increased with age, were higher in A group than in C group. These ROS antioxidant properties of saliva suggested the possibility of clinical evaluation for testing for periodontal disease and early aging, which are also characteristics of DS.