Pumice - A source of fungal cross contamination: An in vitro study

A culture media was used to incubate the pumice samplestaken from dental laboratories for detection of fungi. Pumice is being used in the dental laboratories for polishing of various removable prostheses/dental appliances. Samples were collected from freshly opened packet, storage shelf and pumice pan. They were inoculated on the culture media and incubated for 10 days to detect any presence of fungi. Observation and statistical analysis show the fungal presence in all pumice samples except the samples taken from freshly opened pumice packets. When the fungal colonies were cultivated from other two groups of samples there was statistically significant difference present. The sample from the pan showed the higher number of colony count. It indicates that the particular sample was contaminated through the dental appliances which were polished using that pumice. There are chances that the new prostheses may also be contaminated if proper care is not taken to decontaminate the pumice in the pan or use fresh pumice every time. Climatic affect was also studied and found the most favourable conditions for the growth of fungi was monsoon season.