Comparative antimicrobial effectiveness of a substantive (0.12% chlorhexidine) and a nonsubstantive (phenolic) mouthrinse in vivo and in vitro.

Antimicrobial mouthrinses can play an important role in maintaining oral health by killing cariogenic organisms and preventing plaque and gingivitis. The active ingredients are adsorbed by oral tissues and then gradually released into the saliva. In this article, the effectiveness of a substantive chlorhexidine and a nonsubstantive phenolic antimicrobial mouthrinse were tested. When compared, the results indicated that the two types of mouthrinses are equally effective at killing salivary microbes for up to 30 minutes after rinsing. The prescriptive substantive rinse, however, continued its microbicidal effect for a longer duration (up to 5 hours) than the over-the-counter nonsubstantive rinse. The substantive rinse showed pronounced and measurable zones of inhibition around each well in the agar diffusion assay where the nonsubstantive rinse showed no zone around any well at any time. The substantive rinse also showed a superior ability to inhibit the growth of 28 oral microbes, including some putative periodontopathogens, which were assayed.

Reduction of oral microbes by a single chlorhexidine rinse.

Because of the continued threat of human immunodeficiency virus and hepatitis B infection, as well as the possibility of cross-infection from microbes, such as the herpesviruses and staphylococci, infection control remains a critical issue in dentistry. A traditional response to the infection-control issue is the use of barrier protection by the practitioner and staff. Little attention has been paid to reducing the number of potential pathogens in the oral cavity before dental procedures as a means of minimizing the potential spread of contagion between patients and treatment providers. A study to determine the effectiveness and duration of a single rinse with 0.12% chlorhexidine gluconate oral antiseptic in reducing the number of microorganisms in the oral cavity is presented.

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.