The effects of a dentifrice containing zinc citrate and 2,4,4' trichloro-2'-hydroxydiphenyl ether.

The effects of a dentifrice which contained 1% zinc citrate and 0.5% of a nonionic antimicrobial agent, 2,4,4' trichloro-2'-hydroxydiphenyl ether on plaque and gingival health have been investigated. In a 4-day nonbrushing study in which dentifrices were used as slurries, this dentifrice inhibited plaque accumulation significantly more than dentifrices which contained either zinc citrate or Triclosan separately. In a 28-day double-blind cross-over study, a significant reduction in plaque accumulation and improvement in gingival health was demonstrated for the test dentifrice compared to the placebo. The effect was demonstrated with a group of well motivated volunteers who had a good standard of oral health. Analysis of the data suggested that the benefit might be extended to a less motivated population.

Control of gingivitis and calculus by a dentifrice containing a zinc salt and triclosan.

The effect of unsupervised brushing with a dentifrice containing two antiplaque agents, 0.5% zinc citrate and 0.2% triclosan, on gingival health, plaque, supragingival calculus, and the oral flora was compared to brushing with a non-active control dentifrice. Volunteers were given oral hygiene instruction and their teeth were professionally cleaned. They then used a placebo dentifrice for a pre-experimental phase of 1 month, before being stratified into two groups on the basis of their initial plaque, gingival bleeding, and calculus levels, sex, and age. Over the following 6 months, one group used the control while the other used the test dentifrice. Plaque levels, gingival bleeding, and calculus were assessed at baseline and at 3 and 6 months. Supragingival plaque was sampled for microbiological analysis at the initial examination, at 3 and 6 months (conclusion of study period) and 3 months after the study. Representative oral bacteria and the development of bacterial resistance to triclosan were monitored. Results showed that plaque was reduced and gingival health significantly improved during the 1-month pre-experimental period. During the experimental period, this improvement was not maintained by the control group as gingival bleeding and calculus increased. In contrast, gingival bleeding and calculus levels of the test group were maintained significantly below those of the placebo group. Plaque levels were lower in the test group after 3 and 6 months, but the groups were not significantly (P = 0.05) different. No shifts in oral flora or development of bacterial resistance to triclosan were detected.

Human oral retention of zinc from mouthwashes containing zinc salts and its relevance to dental plaque control.

Subjects using 30 mM zinc phenolsulphonate as a mouthwash retained 12 per cent of the zinc. Salivary zinc concentration was increased by using mouthwashes containing 17-35 mM zinc as the sulphate, phenolsulphonate or citrate. For 17 mM zinc sulphate or phenolsulphonate, the effect lasted 3-4 h. Zinc retained in the mouth gave visible fluorescence after rinsing with 8-hydroxyquinoline and was particularly evident on the tongue, cheek mucosa and dental plaque. The concentration of zinc in plaque was increased 13-19-fold 1 h after using 31 or 18 mM zinc phenolsulphonate. A 3-fold increase was still present 6 h later for the 31 mM mouthwash. Zinc salts inhibited acid production from [14C]-glucose in vitro by plaque at concentrations which were found in plaque in vivo after using the mouthwashes. The effect of zinc on the metabolic activity of plaque may reduce the growth rate of plaque-bacteria and so decrease plaque growth.

Effect of a single dental health care instruction and prophylaxis on gingivitis.

This study was conducted to evaluate the effect of a single dental health instruction on gingivitis in an adult population. Ninety-eight army recruits from two military camps were randomly allocated to four groups: a control group, a group that received a professional prophylaxis, a group that received dental health care instruction and a group that had both a prophylaxis and dental health care instruction. Treatment effects were measured 1 week, 1 month and 3 months after the initial examinations. The single prophylaxis resulted in a small temporary improvement. The effect of the single dental health care instruction was also small, but lasted until the end of the trial. A single instruction plus prophylaxis resulted in the clearest improvement, which was still present after 3 months. It can be concluded that any single treatment should at least consist of dental health care instruction plus a prophylaxis.

Clinical investigation of the effects of dentifrices on dentin wear at the cementoenamel junction.

A two-year clinical study was conducted in vivo to assess the dentin wear caused by dentifrices; results were correlated and compared with those obtained in vitro.

The effect of dentifrices containing Triclosan on the development of gingivitis in a 21-day experimental gingivitis study.

The aim of this study was to investigate the ability of Triclosan dentifrices to delay the development of gingivitis during a 21-day period without toothbrushing. Test pastes contained 0.3 per cent Triclosan; seven also contained 0.75 per cent zinc citrate; one other contained 2 per cent Gantrez. Plaque and gingivitis increased significantly (p < 0.001) between day 0 and day 21 in the control group. there was no evidence to reject the assumption of similar efficacy across the seven Triclosan/zinc citrate variants. For the combined Triclosan/zinc citrate groups, statistically significant reductions in plaque formation and in gingivitis relative to the control were recorded. Reductions in plaque and gingival bleeding compared to control for the Triclosan/Gantrez group were not statistically significant, although reductions in gingival indices were. The greater reduction in the Gingival Index of the Triclosan/zinc citrate group was also statistically significantly different from that of the Triclosan/Gantrez group, suggesting that a dentifrice containing the former would have a greater antigingivitis potential than a dentifrice containing the latter.

The effects of a silica dentifrice containing Triclosan and zinc citrate on supragingival plaque and calculus formation and the control of gingivitis.

A double blind, 7-month parallel clinical study was conducted to determine the effect of a dentifrice containing 0.3 per cent Triclosan and 0.75 per cent zinc citrate in a 0.8 per cent sodium monofluorophosphate/silica base on supragingival plaque, gingivitis and supragingival calculus formation, compared to a 0.8 per cent monofluorophosphate/silica control dentifrice. The results of this clinical study demonstrate that the use of the Triclosan/zinc citrate dentifrice over a 7-month period provided a statistically significant and clinically relevant benefit in controlling gingivitis, compared to a control dentifrice. Supragingival plaque and calculus levels were also significantly reduced in comparison to the effects of a control dentifrice.

Antibacterial dentifrices. Clinical data and relevance with emphasis on zinc/triclosan.

The present review concerns the effect on plaque and gingivitis of some antibacterial dentifrices. The difficulties of including cationic agents in conventional dentifrice formulations are briefly discussed. The focus is on 2 recently introduced dentifrices with triclosan as the active ingredient. One aims at providing a slow release reservoir of triclosan in the oral cavity by delivering the substance dissolved in a lipophilic copolymer. 3-month results indicate a modestly improved effect on plaque and gingivitis compared to that of triclosan alone. Long-term studies are needed before conclusions on the clinical relevance can be drawn. The other dentifrice on the market utilises the principle of additive effects by combining triclosan and zinc citrate in the formulation. The combination appears to be more effective against plaque and gingivitis than either compound alone. Studies of up to 1 year duration indicate that the level of oral hygiene and gingival health obtained through an initial period of motivation and oral hygiene instruction can be maintained by regular use of the test dentifrice, while most subjects in the control group returned to pre-experimental levels. Microbiological monitoring indicates no major shifts in plaque ecology nor any development of resistant bacteria, and adverse side-effects have not been observed. It is concluded that the new approaches to chemical plaque control may be beneficial to the population at large, and thus of great clinical relevance.

Concentration of antimicrobial proteins in human saliva. The effect of six months use of an antiplaque dentifrice on levels of antimicrobial proteins in unstimulated saliva from 102 adults.

Student nurses (aged 20-26 years) were assigned to two groups that were matched for plaque levels and gingival health. For six months, one group used a standard fluoride dentifrice while the other used an identical dentifrice to which zinc citrate (1%, w/w) and Triclosan (0.2%, w/w) had been added. Levels of natural antimicrobial proteins (lysozyme, lactoferrin, salivary peroxidase and Immunoglobulin A) in whole, unstimulated saliva taken from the students at the start and on completion of the six months were measured. No statistically significant differences were found in the levels of antimicrobial proteins in saliva between the test and placebo groups.

The effect of a dentifrice containing zinc citrate and Triclosan on developing gingivitis.

A partial mouth experimental gingivitis model was employed to establish the potential efficacy of a dentifrice containing a zinc salt and the antimicrobial agent Triclosan to prevent or delay the development of gingivitis over a period of 28 days. Initially, gingival health was established in 34 subjects following a 6-week period of professional tooth cleaning and oral hygiene instruction. A toothshield was constructed to fit 4 posterior mandibular teeth. Undiluted test or placebo dentifrice was applied to the experimental teeth via the toothshield, which also prevented plaque removal from these teeth during habitual brushing of the remainder of the dentition. The presence of plaque, bleeding after probing and visual signs of inflammation were independently assessed. Plaque accumulated rapidly and gingivitis developed in both groups. At the 2-wk assessments, lower mean plaque scores were recorded for the group using the test dentifrice. At the 4-wk assessment a significantly lower level of gingivitis was recorded for the test group. It is concluded that (a) the model can be used to establish the potential efficacy of a dentifrice to maintain gingival health, (b) the dentifrice containing zinc citrate and Triclosan was efficacious and (c) the Gingival Index possibly overestimates the proportion of healthy gingival sites.

Antiplaque effects and mode of action of a combination of zinc citrate and a nonionic antimicrobial agent.

The effect upon plaque growth of adding a nonionic antimicrobial agent, triclosan, to a dentifrice containing zinc citrate was established in short-term in vivo studies. Plaque regrowth was inhibited by brushing with dentifrices which contained either zinc citrate or triclosan. When both were combined in the same dentifrice, the inhibition of overnight plaque regrowth was significantly greater. In two 4-day non-brushing studies, the dentifrices containing both zinc citrate and triclosan were applied either undiluted by the use of a cap splint or as 23% suspensions in water. Both methods resulted in significant reductions in plaque accumulation, with the greater activity being observed for the undiluted application of the dentifrice. Analysis of results of the overnight plaque studies for individual teeth revealed that the two agents had a complementary inhibitory action on plaque regrowth, zinc citrate being more effective on existing plaque whereas triclosan inhibited plaque formation on clean surfaces. The dentifrice containing both agents was effective against both existing plaque and new plaque formation. It is concluded that the addition of triclosan to a dentifrice containing zinc citrate improves its antiplaque potential.

Administration to man of UK-37,248-01, a selective inhibitor of thromboxane synthetase.

Pairs of healthy male volunteers received single oral doses (5-200 mg) of UK-37,248-01, a selective thromboxane synthetase inhibitor. Measurement of total thromboxane B2 (TXB2) concentrations in serum from venous blood showed that production of TXB2 was inhibited in a dose-related manner, with peak inhibition 1 h after doses of 50 mg and above. After 100 mg and 200 mg doses TXB2 production was inhibited by more than 90% at 1 h and about 50% at 6 h. Plasma drug assays confirmed oral absorption. About one-third of the dose was excreted unchanged in the urine, most within the first 4 h. Small and transient increases in bleeding time (within the normal range, except in one subject) were seen after the 50, 100, and 200 mg doses and corresponded to low levels of TXB2 production; whole blood clotting time was unchanged. There were no clinically relevant changes in heart rate or blood-pressure, other than a transient reduction in standing systolic blood-pressure and heart rate in one subject who received 200 mg. There were no side-effects and routine laboratory tests revealed no important abnormalities.

The effect on plasma prolactin, growth hormone and luteinising hormone concentrations of single oral doses or propranolol and tolamolol in normal man.

In a placebo controlled double-blind study in six healthy male volunteers the effects of single oral doses of 100 mg and 200 mg of tolamolol on plasma concentrations of prolactin, growth hormone and luteinising hormone were investigated. In a second placebo controlled single-blind study in a further six healthy male volunteers the effects of single oral doses of 200 mg tolamolol and 160 mg propranolol on the same plasma hormone concentrations were compared. A dose dependent increase in plasma prolactin concentration was demonstrated after tolamolol. The increase in plasma prolactin concentration was not evident after propranolol. Plasma growth hormone and luteinising hormone concentrations were not significantly changed by either propranolol or tolamolol.

Microbiological and clinical effects of a dentifrice containing zinc citrate and Triclosan in the human experimental gingivitis model.

A partial mouth experimental gingivitis model was employed to establish the effect of a dentifrice containing 0.2% Triclosan and 0.5% zinc citrate on the development of chronic gingivitis. In addition, changes in the plaque flora associated with the developing gingivitis have been monitored. Following a period of stringent oral hygiene, volunteers were allocated to 1 of 2 treatment groups. A toothshield was constructed to fit 4 posterior mandibular teeth. During the 21-day experimental period test or placebo dentifrice was applied to the experimental teeth via the tooth shield. The toothshield also prevented plaque removal from those teeth during habitual brushing of the remaining dentition. Supragingival plaque was collected at baseline and day 21 for analysis of the total bacterial flora. At the end of the experimental period, plaque and gingivitis had developed in both groups. However, the test group had significantly less plaque and gingivitis than the placebo group. The microbiological data demonstrated that plaque from the test group contained significantly lower numbers of anaerobes compared to plaque from the placebo group. This was considered particularly significant as these bacteria are generally associated with chronic inflammatory periodontal disease. There was also a trend for the numbers of actinomyces to decrease in plaque from the test group but not in the placebo group.