Health Indicator Bacteria That Is Useful for Risk Assessment of Peri-Implantitis

We established a novel identification method for oral Rothia species using one-step multiplex PCR analysis to investigate whether the monitoring of oral Rothia species levels is useful for peri-implantitis risk assessment, and to examine the oxygen concentration that these organisms need for growth in vitro. The mean number and proportion of Rothia aeria in peri-implant sulcus fluid (PISF) samples was significantly higher in the healthy implant group than in the peri-implantitis group (P < 0.05). Moreover, R. aeria under aerobic conditions vigorously grew compared with those under anaerobic conditions, and this organism grew only at the upper layer where high oxygen concentrations existed in a semi-liquid nutrient medium. Therefore, the monitoring of R. aeria levels may be suitable as an indicator of healthy peri-implant tissue conditions for the prevention of peri-implantitis.