Reduction of salivary bacteria by pre-procedural rinses with chlorhexidine 0.12%

The purpose of this study was to assess the effect of pre-procedural rinsing (2 consecutive rinses) with 0.12% chlorhexidine gluconate (CHX) on salivary bacteria during scaling and root planing procedures (S&RP). Because blood and debris arising from S&RP could inactivate CHX and decrease its antimicrobial effect, patients were evaluated throughout their appointment. Forty subjects rinsed with either 15 ml of CHX rinse or control (sterile water) for 30 seconds, expectorated and immediately rinsed again for 30 seconds. Unstimulated saliva samples were obtained at baseline (immediately before rinsing), and at 1 minute, 30 minutes, and 60 minutes after baseline. All 30 and 60 minute samples contained visible blood and debris. Samples were immediately diluted in transport fluid containing a CHX-neutralizer and then plated on trypticase soy agar for enumeration of the total aerobic and facultative bacterial load. The dual rinses with 0.12% CHX immediately reduced the salivary bacterial load 97% and this reduction persisted for 60 minutes during S&RP. At 30 minutes and at 60 minutes aerobic bacteria were reduced 77% compared to control, and 96% compared to baseline. CHX was not inactivated by the high organic load (blood and debris) present during the procedure. Pre-procedural rinsing with CHX has a profound and sustained effect on the aerobic and facultative flora of the oral cavity, which may contribute to a variety of clinical benefits. Pre-procedural rinsing may also be of value in protecting patients and dental professionals during dental manipulations.