Randomized controlled trial: lip piercing: the impact of material on microbiological findings

PURPOSE The purpose of this study was to investigate whether there are microbiological differences in bacterial samples collected from labial piercings made of different materials. METHODS Sterile piercings of 4 materials were randomly allocated to 80 pierced subjects. After 2 weeks, microbiologic samples were collected and processed by checkerboard DNA-DNA hybridization methods. Wilcoxon signed ranks and Mann-Whitney tests were used for statistical analysis (adjustment for multiple comparisons). RESULTS There were no statistically significant differences between material groups in relation to baseline data. In samples from stainless steel piercings, the total microbial load was significantly higher than the other materials (P<.05). Ten (mainly periopathogenic) species were found at significantly higher levels (P<.001) on steel than on polypropylene and/or polytetrafluoroethylene piercings. CONCLUSIONS Labial piercings made of stainless steel could promote the development of a pathogenic biofilm.