ABSTRACT

The aim of this study was to examine the effect of orthodontic appliances on antimicrobial and antioxidant capacity of the saliva. For this purpose seventeen children (11 girls, 6 boys) aged between 12–20 years with no systemic disease were selected. Unstimulated whole saliva sample was collected before orthodontic treatment of each patient. The sample collection was repeated on third and sixth month after the placement of brackets, bands and wires. AH saliva samples were kept at −35°C until studied. The antimicrobial protein lysozyme assays were performed by the method of Osserman and Lawlor. The antioxidant defense enzyme superoxide dismutase (SOD) activity was measured using the nitroblue tetrazolium assay. The protein content was measured by the method of Lowry. The data were evaluated statistically with paired-t test. Three months after the placement of orthodontic appliances, lysozyme levels were unchanged; however they were significantly reduced on the sixth month of treatment (1.11 ±0.62 mg/mg protein vs 0.63±0.41 mg/mg protein; p<0.05). On the other hand, SOD activity was continuously elevated following the treatment. Mean SOD activity in saliva was 3.93±1.73 U/mg protein on the third month, and 5.21+2.19 U/mg protein on the sixth month which were both significantly higher than the basal level (2.83+1.26 U/mg protein; p<0.01). No significant difference in the total protein content in unstimulated saliva was observed between the three stages of the study. It is concluded that fixed orthodontic appliances may alter the antibacterial and antioxidant capacity of the saliva following a six-month treatment.