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

The infection transmission by impression 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, Hydrogum and Orthoprint] and 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 incubaction in37 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

evaluation of occlusal contacts of remounted complete denture before final occlusal adjustment

There are various studies about the advantages and effect of remounting procedures on success of complete dentures; however, the number and distribution of occlusal contacts of remounted complete dentures before occlusal adjustment have not been sufficiently assessed. The purpose of this study was to evaluate the distribution and number of occlusal contacts of remounted complete dentures in centric relation before occlusal adjustment. In this cross-sectional study, 207 newly constructed complete dentures were remounted on a modified two dimensional articulators. For identification of occlusal contacts, a 60 micron articulating paper was used to mark the actual contacts of the opposing teeth. The articulating paper was interposed between the teeth, and contacts were obtained by holding the articulating paper between the opposing teeth. The number and distribution of the occlusal contacts on each complete denture in centric relation were recorded and analyzed, using descriptive statistics. Out of the 207 studied complete dentures, 203 had occlusal contacts. Among 203 complete dentures, 138 [68%] and 65 [32%] had bilateral and unilateral occlusal contacts, respectively. The total number of occlusal contacts was 713 with a range of 1-14. The mean number of occlusal contacts was 3.44 +/- 2.29. The results suggest that the number of occlusal contacts of remounted complete dentures before occlusal adjustments by articulating paper was low, the posterior teeth did not meet evenly all around the arch at the first contact, and delivery of such complete dentures may lead to occlusal error and unstable complete denture