Effect of an antiseptic mouthrinse on salivary microbiota.

PURPOSE: To evaluate the effect of rinsing with original formulation Listerine Antiseptic (LA) on the level of viable salivary bacteria for periods up to 1 hour. MATERIALS AND METHODS: In this double-blind, controlled, cross-over study, unstimulated saliva was collected from 25 subjects, serially diluted, and cultured on selective and non-selective media under aerobic and anaerobic conditions. Streptococci, Veillonella sp., and total aerobic and anaerobic flora were enumerated just prior to and 2, 15, 30, and 60 minutes after rinsing for 30 seconds with either 20 ml of LA or a 5% hydroalcohol control rinse. RESULTS: After the control rinse, total flora cultivated on MM10 agar exhibited a non-significant (P > 0.05) 10%-20% decrease relative to baseline. In contrast, rinsing with LA resulted in a significant (P < 0.05) 60%-65% decrease from baseline in all four microbial groups at 2 minutes; except in the case of Veillonella, the significant decreases were sustained up to 60 minutes. Total Listerine group aerobic, anaerobic and streptococcal counts were significantly lower than placebo (P < 0.05). The significant reduction in salivary bacterial levels seen in the Listerine group for up to 60 minutes suggests that this antiseptic mouthrinse may have use clinically as a pre-procedural rinse to decrease the level of viable microorganisms in aerosols generated during dental procedures.

Early appearance of antibodies to simian immunodeficiency virus in saliva and serum of infected macaques.

Simian immunodeficiency virus (SIV) infection in macaques is an important animal model for human immunodeficiency virus infection in humans. This study evaluated the temporal development of antibodies to SIV in the parotid saliva of macaques inoculated with the virus and compared these findings with the development of antibodies to SIV in the animals' sera. Three animals (ages, 14, 18, and 18 years) were inoculated with the macrophagetropic strain SIVmac239. Prior to inoculation and at consecutive weekly intervals during a four-week period following the initial virus inoculations, parotid saliva and serum were collected from each animal. A fourth animal (age, 9 years) served as a negative control, and the fifth and sixth animals (ages, 2 and 22 years) served as positive controls (6 and 18 months postinoculation, respectively) with SIVmac239. Saliva and serum samples were reacted against SIV antigen in Western blots (immunoblots) prepared in the standard fashion to determine the presence of antibodies. The reactions of these antigen-antibody complexes with biotinylated anti-human immunoglobulin A (IgA), IgM, and IgG and biotinylated anti-human secretory component (SC) determined the class of antibody present or the presence of SC in the original parotid saliva or serum samples. In infected animals, the IgM to SIV was detectable in serum and saliva at 13 days, and antiviral IgA and IgG in serum and saliva were detectable at 20 to 27 days postinoculation. The antibody to SC reacted to saliva from only two animals at 20 and 27 days, and long-term positive controls were positive for SC in saliva, indicating that either secretory IgA or secretory IgM was present in these samples. Antibodies to SIVmac239 antigens have therefore been detected in saliva as early as 13 days postinfection. Saliva may be as useful as serum as a diagnostic specimen and/or disease-monitoring method in this important animal model.

Effect of an antimicrobial mouthrinse on recurrent aphthous ulcerations.

Recurrent aphthous ulceration (RAU) remains a clinical problem for many patients. Efforts in prevention and/or treatment with prescription and nonprescription formulations have to date resulted in minimal success at best. A 6-month double-blind clinical study of 96 adults compared a commercially available antimicrobial mouthrinse (Listerine Antiseptic [LA], Warner-Lambert Co., Morris Plains, N.J.) and a hydroalcoholic control to evaluate the effects of vigorous twice-daily rinsing on the incidence, duration, and severity of RAU in persons prone to this disorder. LA rinse and the hydroalcoholic rinse resulted in a statistically significant reduction in the incidence of RAU occurrences from baseline. The duration of lesions and the severity of pain in subjects with ulcers during the treatment period were also significantly reduced in the LA rinse group of patients when compared with baseline. The hydroalcoholic rinse did not show a significant effect versus baseline for either severity or duration of the lesions. Rinsing therefore can be of clinical value in reducing the occurrence of RAU in susceptible patients, and LA rinse can be of significant additional value in decreasing the duration and severity of RAU.

Effect of granulocytopenia on oral microbial relationships in patients with acute leukemia.

Risk for acute infection increases as granulocyte levels decrease secondary to myelosuppressive chemotherapy in patients with acute nonlymphocytic leukemia (ANLL). Acute exacerbations of concomitant inflammatory periodontal diseases can result in systemic infections in these patients. However, host-oral bacterial relationships in the periodontium in patients with ANLL are not well understood. Twenty-one adult patients with ANLL with periodontal disease ranging from gingivitis to severe periodontitis were studied. Supragingival and subgingival plaque specimens were collected before chemotherapy (prechemotherapy), and at a defined midpoint of myelosuppression (midchemotherapy; day 14). All specimens were extensively cultured both aerobically and anaerobically. Data were submitted to a partial correlational analysis, controlling for covariation relation to oral hygiene intervention and antibiotic administration. Levels of total yeast exhibited a significant association with Staphylococcus sp. at supragingival sites midchemotherapy (r = 0.68, p less than or equal to 0.05). Levels of total yeast also correlated positively with Pseudomonas aeruginosa at subgingival sites both prechemotherapy (r = 0.70, p less than or equal to 0.01) and midchemotherapy (r = 0.61, p less than or equal to 0.05). Significant correlations of levels of Veillonella sp. with Neisseria sp. and gram-negative enteric bacilli were observed in both supragingival (r = 0.95, 0.77, p values less than or equal to 0.01) and subgingival (r = 0.69, 0.61, p values less than or equal to 0.05) plaque specimens midchemotherapy but not prechemotherapy. These data suggest that potentially pathogenic bacteria occur in plaque simultaneous with granulocytopenia in these patients. Multiple mechanisms, including intergeneric coaggregation and other symbiotic relationships, may influence infectivity of the mixed plaque flora and thus contribute to the oral ecology observed in these patients.

Comparative effects of 2 chemotherapeutic mouthrinses on the development of supragingival dental plaque and gingivitis.

A 6-month double-blind, controlled clinical study was completed with 124 healthy adult subjects to determine the efficacy of 2 mouthrinses, Listerine (LA) and Peridex (PX), used as supplements to regular oral hygiene measures in reducing supragingival dental plaque and gingivitis. Following screening examinations for entry levels of existing gingivitis and plaque, baseline gingival and plaque area indices, extrinsic tooth stain, supragingival calculus, bleeding and soft tissue condition were recorded. All subjects then received a complete dental prophylaxis to remove plaque, calculus and extrinsic stain. Subjects were randomly assigned to 1 of 3 groups and performed supervised rinses twice daily for 30 s in addition to their normal oral hygiene, for 6 months. All indices were again evaluated at 3 and 6 months. After 6 months, LA and PX significantly (p less than 0.001) inhibited development of plaque by 36.1% and 50.3%, respectively, and the development of gingivitis by 35.9% and 30.5%, respectively, compared to a hydroalcohol control. PX was more effective in inhibiting plaque and both mouthrinses appeared to be equally effective in inhibiting gingivitis. LA patients did not develop significant levels of stain or supragingival calculus at 6 months, compared to baseline or control. PX patients developed significant levels of extrinsic stain and supragingival calculus compared to baseline and control. Though PX was more effective than LA in the control of plaque, this study indicates that both LA and PX were effective agents in a regimen for the control of plaque and gingivitis.

Incidence of fever following invasive oral interventions in the myelosuppressed cancer patient.

Oral complications in cancer patients with chemotherapy-induced myelosuppression contribute to morbidity and mortality. However, guidelines for oral care to prevent such complications, including disorders involving the periodontium, are not clear. This study specifically analyzed the impact of a noninvasive oral examination versus invasive oral interventions (periodontal probing, dental scaling) prior to chemotherapy on subsequent development of fever and/or bacteremia in these patients. Medical and dental records were reviewed for 100 patients who had been assigned to receive either the invasive or noninvasive procedures prior to chemotherapy. Temperature values immediately before and up to 48 h after the oral intervention were recorded, and the occurrence of fever and/or bacteremia was documented for each group. There was no statistically significant difference in the incidence of fever and/or bacteremia between the two groups of patients. Although periodontal probing and dental scaling are procedures that invade mucosal barriers, such interventions did not appear significantly to affect the incidence of fever or bacteremia among persons in this study.

Effects of 6 months use of an antiseptic mouthrinse on supragingival dental plaque microflora.

This study was undertaken to determine whether long-term use (6-months) of an antiseptic mouthrinse (Listerine Antiseptic, Warner Lambert Co., Morris Plains, NJ, USA) led to an undesirable succession of oral pathogens or the emergence of resistant microbial forms. Supragingival plaque was collected from 83 subjects before treatment and after either 3 or 6 months use of either the active antiseptic or a 5% hydroalcohol control. Subjects rinsed with their assigned mouthrinse twice daily under supervision. The plaque samples were analyzed for microbial content by darkfield microscopy, culture on a series of nonselective and selective bacterial media, and by recognition of microbial forms by recognition of distinct colony on a nonselective medium. Statistical analysis of the results revealed no significant microbial shifts including no significant increases in presumptive oral pathogens, spirochetes, black-pigmented Bacteroides, Streptococcus mutans, or Candida albicans. Additionally, no detectable rise in either staphylococci or enteric bacteria, potential opportunistic pathogens, was observed.

Chemotherapeutic inhibition of supragingival dental plaque and gingivitis development.

A 6-month double-blind, controlled clinical study was conducted on 107 healthy adult subjects to determine the efficacy of a mouthrinse used as a supplement to regular oral hygiene measures on supragingival dental plaque and gingivitis. 115 healthy adult patients were recruited for the study. Following screening examinations for minimal entry levels of existing gingivitis and plaque in patients with a minimum of 20 sound natural teeth, extrinsic tooth stain, gingivitis and plaque index scores were recorded. Soft tissues were evaluated. All subjects then received a complete dental prophylaxis, removing plaque, calculus and extrinsic stain. Utilizing their normal oral hygiene, subjects began a regimen of rinsing with 20 ml of the randomly assigned rinse, twice daily for 30 s for 6 months. 7 days after prophylaxis, gingivitis was again scored (baseline 2). Soft tissue, gingivitis, plaque area and extrinsic stain were evaluated again at 3 and 6 months. Results demonstrated that after 6 months, listerine produced a 34% inhibition of both plaque and of gingivitis compared to a hydroalcohol control (p less than 0.001).

Periodontal disease and oral microbial successions during myelosuppressive cancer chemotherapy.

Factors contributing to the succession of opportunistic pathogens at oral sites, including the periodontium, during myelosuppressive chemotherapy are poorly understood. This study examined the relation of periodontal disease to qualitative and proportional shifts in the oral microflora of 21 acute nonlymphocytic leukemia patients (7 male and 14 female, mean age (range) = 51.0 (25-81 years) observed during standardized myelosuppressive regimens. Supra- and subgingival microbial plaque specimens were individually collected from 2 contralateral oral sites (distobuccal of teeth 1-6 and 3-6) in each participant at hospital admission (day 1) and during point of maximal myelosuppression (day 14). Periodontal disease indices obtained at day 1 included site-specific measures of attachment loss and clinical assessment of disease status. Using a residualized change score analysis, periodontal disease status and attachment loss were positively correlated with increases in the proportional recovery of Staphylococcus sp. from supragingival sites and total yeast from supra- and subgingival sites. When age-related covariation in the microbial shifts was controlled in the analysis, periodontal disease status and attachment loss demonstrated no significant correlation with increases in total yeast at supragingival sites. These findings suggest that host factors such as periodontal disease may contribute to patterns of oral microbial successions during cancer chemotherapy.

Experimental endocarditis following dental extractions in rats with periodontitis.

This study analyzed the development of bacterial endocarditis following dental extraction in rats with periodontal disease. Periodontal disease was produced in rats by tying silk ligatures around the two maxillary first molars, and placing the animals on a high sucrose diet. Sterile aortic valve vegetations were produced by means of a transaortic catheter, and 24 hours later the maxillary first molars were extracted. The animals were killed 72 hours after the extractions. In rats with periodontal disease induced for 10 and 14 weeks, extractions resulted in an incidence of bacterial endocarditis of 24% and 50%, respectively, most of which were due to streptococcal species (two were caused by Staphylococcus [corrected] aureus). The difference, though not statistically significant (p = 0.10, chi 2 with Yates correction), shows a trend toward increased incidence of endocarditis with increasing severity of periodontal disease. This model demonstrates that one can reliably induce bacterial endocarditis after dental extractions in rats with periodontal disease.

Longitudinal clinical studies with antimicrobial mouthrinses.

This chapter examines the use of long-term clinical studies to evaluate the effectiveness of antimicrobial mouthrinses in the prevention and/or treatment of plaque and gingivitis. Such studies should be double-blind, compare the active agent to a control, and last a minimum of 6 months. Such a time interval simulates a common recall interval, enables one to utilize a thorough dental prophylaxis at the initiation of the study, and is sufficient time to observe the development of toxic and other side-effects of therapy. The microbiological component should estimate plaque quantitatively and demonstrate that no pathogenic, opportunistic or resistant micro organisms develop. The indices and microbiology should be performed at baseline, and intermediate period and at 6 months. Thus far, published studies meeting these criteria support the efficacy of listerine and chlorhexidine as agents useful in reducing plaque and gingivitis. Preliminary evidence indicates that sanguinarine may also be effective. The most common side effect of listerine was the complaint of poor taste. Increased stain and calculus formation were cited as the most significant side-effects of chlorhexidine. Such side-effects must be taken into consideration when recommending effective antimicrobial mouthrinses for patient use.

Predictors of endocarditis in isolates from cultures of blood following dental extractions in rats with periodontal disease.

Rats with periodontitis and catheter-induced aortic valve vegetations underwent dental extractions. Cultures of blood obtained 1 min later showed polymicrobial bacteremia in 19 of 19 rats, mostly due to viridans streptococci (18 of 19), Morganella (15 of 19), group G streptococci (13 of 19), and Staphylococcus aureus (10 of 19). Viridans streptococci circulated in higher numbers than did group G streptococci and S. aureus (P less than .01). Three days after dental extractions, 18 of 20 rats had endocarditis. Fifteen (83%) of 18 infections were due to group G streptococci, 9 (50%) of 18 were due to S. aureus, and 2 (11%) of 18 were due to viridans streptococci (P less than .05). In vitro, adherence to platelet-fibrin matrices of endocarditis strain 8 of group G streptococcus was two times greater than that of endocarditis strain S. aureus 23 and three to four times greater than that of Streptococcus sanguis 44 and Morganella morganii 93 (P less than 10(-5)). The inoculum size that produced endocarditis in 90% of rats after iv challenge was 10(5) cfu for group G streptococcus strain 8 and 10(7) for S. sanguis 44.

Antibiotic prophylaxis of experimental endocarditis after dental extractions.

In rats with catheter-induced sterile aortic valve vegetations we studied the efficacy of single-dose amoxicillin and single-dose erythromycin prophylaxis for the prevention of bacterial endocarditis after extractions of periodontally diseased teeth. Endocarditis after extractions occurred in 89% of control animals and was due to group G streptococci, to Staphylococcus aureus, or to both organisms. A single-dose of amoxicillin or erythromycin successfully prevented endocarditis due to these bacterial species. The analysis of the bacteremia (by culturing blood drawn 1 min after extraction on penicillinase-containing blood agar plates) indicated that amoxicillin did not influence the incidence or the magnitude of circulating group G streptococci and S. aureus, while erythromycin apparently suppressed them. However, when care was taken to eliminate blood erythromycin by a lysis-centrifugation process, the incidence and magnitude of bacteremia after erythromycin prophylaxis was similar to that in control rats. We conclude that single doses of amoxicillin and erythromycin successfully prevent experimental endocarditis after dental extractions. Since this prophylaxis was operative by mechanisms other than the prevention of the circulation of bacteria before seeding the valvular vegetations, it suggests that recommendations for prevention of bacterial endocarditis should not be aimed only at providing adequate antibiotic blood levels to suppress the bacteremia produced by the invasive procedure.

Microbiology of acute periodontal infection in myelosuppressed cancer patients.

This study characterized the subgingival microbial flora associated with 27 acute exacerbations of preexistent periodontal disease in 24 patients with chemotherapy-induced myelosuppression. All but two acute periodontal infections developed at low granulocyte levels (less than 1,000/microL). Suspected pathogens were detected in high concentrations in subgingival plaque specimens in 17 episodes of acute periodontal infection; a single pathogen was recovered in ten acute infections, and more than one pathogen was recovered in seven acute infections. Staphylococcus epidermidis, Candida albicans, S aureus, and Pseudomonas aeruginosa predominated, with combinations of these detected in some patients. Concomitant bacteremias developed in two of these patients. The subgingival microflora associated with ten acute periodontal infections was characterized by predominantly indigenous microorganisms, which in nine episodes were in abnormal proportions compared with microbial profiles in noncancer patients with similar degrees of periodontal disease. These data demonstrate that pathogens normally associated with infections in myelosuppressed cancer patients, as well as indigenous oral flora, are associated with acute periodontal infections during granulocytopenia. This finding is important, since this body site has not commonly been recognized as a source for acute infection in these patients.

Experimental bacterial endocarditis after dental extractions in rats with periodontitis.

The development of bacterial endocarditis was analyzed after dental extractions in rats with or without periodontal disease. Periodontal disease was produced in rats by tying silk ligatures around the two maxillary first molars and placing the animals on a high sucrose diet for 14 weeks. Sterile aortic valve vegetations were produced by means of a transaortic catheter, and 24 hr later the maxillary first molars were extracted. The animals were killed 72 hr after the extractions. In rats with periodontal disease, extractions resulted in a 48% (14 of 29) incidence of bacterial endocarditis, most cases of which were due to Streptococcus spp. (one was caused by Staphylococcus aureus). In contrast, when the teeth with a healthy periodontium were extracted, only 6% (one of 15) of the rats developed endocarditis. When catheters were placed in animals with periodontal disease but no extractions were performed, no endocarditis occurred.