"Comparative evaluation of surface modified elastomeric ligatures for microbial colonization": An in vivo study

Elastomeric ligatures are observed to reduce chair side time; however, they are also seen to have greater bacterial adhesion. Polymeric coating utilizing the Metafasix Technology and the OrthoShield Technology have been introduced in the Super Slick™** and Safe-T-Ties™** by TP Orthodontics, Ortho Organizers, respectively, to reduce bacterial adhesion. While each of the elastomers has been individually evaluated, no study compares the two elastomers manufactured by differing technologies together; hence the need for this study was felt. This in vivo study compared the Super Slick and Safe-T-Ties with their unmodified counterparts for bacterial adhesion.

Thirty patients undergoing orthodontic treatment, between 12 and 25 years age group were selected and the modified, and the unmodified elastomers were randomly placed quadrant wise, on all the premolar brackets. After a period of 4 weeks, the elastomeric rings were removed and transported for culture on Mitis-Salivarius, Rogosa SL agar for Streptococcus mutans and Lactobacilli, respectively. The colonies were digitally counted (HiMedia) after 48 h of incubation at 37°C.

There was a significant difference in the S. mutans and Lactobacilli counts in both surface modified and unmodified elastomeric modules (P < 0.01). Unmodified elastomeric modules Mini Stix™**, Hand-EE-Lasts™** was associated with higher mean values of colony-forming units/millimeter than the surface modified Super Slick™** and Safe-T-Ties™** ligatures. When compared pair-wise, the surface modified elastomers showed less bacterial accumulations than the unmodified counterparts for both S. mutans and Lactobacillus, and the differences were statistically significant.

Technological modifications of the elastomers using the Metafasix or OrthoShield Technology, is a definite improvement over the regular elastomers with regard to adhesion of S. mutans and Lactobacilli.