Comparison of the self-antimicrobial effect of six irreversible hydrocolloid impressions on oral flora microorganisms

The infection transmission by impressions to the laboratory is growing concern for clinicians and laboratory technicians. This study aimed to compare the self-antibacterial effect of six irreversible hydrocolloid impression materials (Iralgin, Xantalgin, Tropicalgin, Plastalgin, Hydrogum and Orthoprint) on oral flora microorganisms.

In this experimental set-up, 108 irreversible hydrocolloid specimens including alginate disks with 1 mm thickness, 5 mm diameter and 30±2 mg weight, and 18 sterile paper disks as negative control specimens (totally 126 specimens) were prepared. These specimens were transferred to Staphylococcus aureus (Group 1), Pseudomonas aeruginosa (Group 2) and Candida albicans (Group 3) fresh microbial environments. After 48 hours incubation in 37 degrees Celsius, the maximum growth inhibition zone diameters were recorded. Statistical analysis was performed by ANOVA or Friedman test.

No zone of inhibition was observed around the control specimens. Iralgin and Tropicalgin specimens had significant growth inhibition on Group 1. Tropicalgin more than Iralgin and Iralgin more than the other specimens significantly inhibited Group 2 microorganisms. Plastalgin specimens had significant growth inhibition on Group 3 (P < 0.05).

Some of the investigated alginates had self-antibacterial effects; however, disinfection of impressions with other techniques are still inevitable.