Methods: A split mouth randomized double blind clinical trial consisting of 34 orthodontic patients (age 10-20 yrs) was conducted. Prior to bonding (T0), the sample was randomly assigned to 2 groups on the basis of follow up time period (T1). Group I (G1) consisted of 24 patients evaluated after 6 weeks from initial bonding, while Group II (G2) consisted of 10 patients evaluated after 4 weeks. Each group was further randomly divided to receive test ligatures on right or left side. For both groups EL were collected for microbiological testing at T1. All patients received pre-adjusted edgewise stainless steel brackets (Unitek, USA) and a non fluoride releasing, no-mix light cure bonding resin (Transbond, Unitek, USA). Standardized dietary and hygiene advice was given verbally and by providing printed brochures and consisted of twice daily brushing with conventional and inter-dental brushes with fluoridated tooth paste. Use of fluoride mouth wash was not recommended.
Results: Paired student T-test was applied. Total bacterial count at 6 weeks was found to be higher in Selenium impregnated EL (8.96 CFU’s/1000 ml) compared to conventional EL (2.43 CFU’s/1000 ml) and the difference was statistically significant (p<0.05). At 4 weeks no statistically significant difference was found for total bacterial count between the two EL. S.mutans count also showed no statistically significant difference between Selenium impregnated EL and conventional EL both at 6 and 4 weeks .
Conclusions: The clinical trial showed that use of Selenium impregnated elastomeric ligatures was not effective at reducing total bacterial count in orthodontic patients at 4 or 6 weeks.
Keywords: Antimicrobials, Microbiology, Orthodontics and Selenium ligatures