Retention and plaque-inhibiting effect in man of chlorhexidine after multiple mouth rinses and retention and release of chlorhexidine after toothbrushing with a chlorhexidine gel.

The retention of chlorhexidine was measured during 10 consecutive 15-s mouth rinses with 10ml of 0.05, 0.10 and 0.20 per cent (w/v) [¹⁴C]-chlorhexidine-digluconate; the 0.05 per cent concentration was also tested in 20-ml volumes. Multiple mouth rinses led to accumulated retention of the drug in the mouth; increasing the rinsing volume increased the retention.Rinsing twice with 20 ml of 0.05 per cent chlorhexidine-digluconate twice daily was effective in plaque inhibition in a sucrose-stimulated plaque model.Toothbrushing with 1 g of a 1.0 per cent (w/w) chlorhexidine-digluconate gel led to a retention of chlorhexidine ≈ the retention after a 0.10 per cent (w/v) chlorhexidine mouth rinse. The release of chlorhexidine into saliva during the following 24 h followed the same pattern as observed earlier after chlorhexidine mouth rinses.     

Influence of ionic strength, calcium, sodium dodecyl sulphate and urea on the retention of chlorhexidine in the human mouth after mouth rinses.

The retention of chlorhexidine after mouth rinses was measured using [¹⁴C]-chlorhexidine. Corrections were made for the fraction swallowed by the use of [⁵¹Cr]-EDTA. Plaque inhibition was measured in 3-day trials, in which sucrose stimulation was employed every second hour from 8 a.m. to 10 p.m. The concentration employed was usually 1.1 mM chlorhexidine-digluconate, the volume 10 ml, and rinsing time 1 min.The presence of 250 mM calcium in the mouth rinse solution decreased the retention significantly. The release of chlorhexidine from the mouth into three consecutive 10 and 1-min after-rinses following a 1.1 mM chlorhexidine mouth rinse increased from 19 per cent of the initial retention with water after-rinses to 54 per cent of the initial retention with 250 mM calcium present in the after-rinses (n = 8).Increasing the ionic strength of the after-rinses following a chlorhexidine rinse increased the release of chlorhexidine significantly. Inclusion of 25 mM sodium dodecyl (lauryl) sulphate in the chlorhexidine rinsing solution reduced both the retention and the plaque inhibition greatly. Inclusion of 5 M urea in the rinsing solution reduced the retention significantly, but did not influence the plaque-inhibiting effect.     

Retention of chlorhexidine in the human oral cavity after mouth rinses

The retention of chlorhexidine after mouth rinses was measured by the use of [¹⁴C]-chlorhexidine. The fraction swallowed was estimated using [⁵¹Cr]-EDTA. The mean total retention after 0.2 per cent chlorhexidine-digluconate mouth rinses (10 ml for 1 min) averaged 34 ± 7 per cent (6.9 ± 1.4 mg), and the oral retention 30 ± 7 per cent (6.0 ± 1.5 mg).The intra-individual variation, estimated by five mouth rinses at 1-week intervals, averaged ±4 per cent.The ¹⁴C-activity in saliva showed a sharp fall during the first few hours, followed by a slow release, with activity still present after 24 hr.     

Oral pharmacology of chlorhexidine

Abstract The paper concerns factors which affect the binding and plaque-inhibiting effect of chlorhexidine-digluconate (CH) in the human oral cavity. About one-third of the administered dose was retained after mouth rinses (0.05-0.40 % w/v) and after toothbrushing with a CH gel (1 % w/w) measured by [¹⁴C]-chlorhexidine. The following CH concentration in saliva showed an almost logarithmic fall during the first 4-8 h, followed by a more steady low concentration, with CH still present after 24 h. The amount retained after mouth rinses increased almost linearly with the increase in the concentration. Time studies showed that about 55 % of the amount retained after 60 sec was retained after the first 15 sec. Lowering the pH of the rinsing solution reduced the retention, and increase in ionic strength of after-rinses increased the release of CH. Calcium in a 250 mM concentration significantly reduced the retention and increased the release when present in after-rinses. The detergent sodium dodecyl (lauryl) sulphate greatly reduced both the retention and the plaque-inhibiting effect. Comparative studies between CH and quaternary ammonium compounds showed that 60-65 % of the quaternaries was retained, compared to 32 % of CH. When used four times daily, the plaque-inhibiting effect of the quaternaries approached that of CH. Their concentration in saliva fell more rapidly than that of CH.     

The effect of mouthrinses and topical application of chlorhexidine on the development of dental plaque and gingivitis in man

Twenty-four male dental students with healthy gingivae and clean teeth ceased all oral hygiene procedures. (A) Four subjects rinsed, twice daily, with a 0.2 per cent solution of chlorhexidine gluconate; (B) eight students rinsed, once daily, with the same solution; (C) six students did not rinse and formed the control group and (D) six students received one daily application of a 2 per cent solution of chlorhexidine gluconate. The study confirmed previous observations (Löe and Rindom Schiött 1969, 1970) that two daily mouth rinses with a 0.2 per cent solution of chlorhexidine effectively prevent plaque formation. One daily rinse did not inhibit plaque formation in all areas of the dentition. One daily topical application of a 2 per cent solution of chlorhexidine gluconate prevented plaque formation completely. Upon discontinuation of the chlorhexidine treatment plaque formed at normal rates, suggesting that there is no appreciable effect beyond a 24 hour period. It is concluded that complete inhibition of plaque and prevention of gingivitis may be achieved by daily application of chlorhexidine, provided the agent is administered in such a way that it reaches all tooth surfaces.     

Comparison of the effects of cetylpyridinium chloride with an essential oil mouth rinse on dental plaque and gingivitis - a six-month randomized controlled clinical trial

Objective: To compare the effects of an experimental mouth rinse containing 0.07% cetylpyridinium chloride (CPC) (Crest Pro‐Health^®) with those provided by a commercially available mouth rinse containing essential oils (EOs) (Listerine^®) on dental plaque accumulation and prevention of gingivitis in an unsupervised 6‐month randomized clinical trial. Material and Methods: This double‐blind, 6‐month, parallel group, positively controlled study involved 151 subjects balanced and randomly assigned to either positive control (EO) or experimental (CPC) mouth rinse treatment groups. At baseline, subjects received a dental prophylaxis procedure and began unsupervised rinsing twice a day with 20 ml of their assigned mouthwash for 30 s after brushing their teeth for 1 min. Subjects were assessed for gingivitis and gingival bleeding by the Gingival index (GI) of Löe & Silness (1963) and plaque by the Silness & Löe (1964) Plaque index at baseline and after 3 and 6 months of rinsing. At 3 and 6 months, oral soft tissue health was assessed. Microbiological samples were also taken for community profiling by the DNA checkerboard method. Results: Results show that after 3 and 6 months of rinsing, there were no significant differences (p=0.05) between the experimental (CPC) and the positive control mouth rinse treatment groups for overall gingivitis status, gingival bleeding, and plaque accumulation. At 6 months, the covariant (baseline) adjusted mean GI and bleeding sites percentages for the CPC and the EO rinses were 0.52 and 0.53 and 8.7 and 9.3, respectively. Both mouth rinses were well tolerated by the subjects. Microbiological community profiles were similar for the two treatment groups. Statistically, a significant greater reduction in bleeding sites was observed for the CPC rinse versus the EO rinse. Conclusion: The essential findings of this study indicated that there was no statistically significant difference in the anti‐plaque and anti‐gingivitis benefits between the experimental CPC mouth rinse and the positive control EO mouth rinse over a 6‐month period.     

The comparative effect of acidified sodium chlorite and chlorhexidine mouthrinses on plaque regrowth and salivary bacterial counts

Abstract Acidified sodium chlorite (ASCI is recognised as a highly potent, broad spectrum antimicrobial system that has been successfully developed for uses in veterinary, food processing and medical device fields. The current studies aimed to investigate the persistence of antimicrobial action and plaque inhibitory properties of 3 ASC mouthrinses by comparison with positive control, chlorhexidine 0.12%, and placebo control, water, rinses. Both studies were randomised, double-blind, cross-over 5-cell designs balanced for carryover. The 1st study involved 15 healthy subjects who immediately before and at 30, 60, 180, 300 and 420 min after rinsing provided 2 ml saliva samples. The samples were immediately processed for total anaerobic bacterial counts recorded after 96 h incubation. Washout periods were a minimum of 3 days. The second study involved 20 healthy subjects who on day 1 of each study were rendered plaque free, suspended normal oral hygiene methods and commenced rinsing twice daily with the allocated rinse. On day 5, plaque was scored by index and area after disclosing with erythrosin. Washout periods were 2 1/2 days. The 3 ASC and chlorhexidine rinses produced similar reductions in salivary bacterial counts which remained significantly below the placebo control to 7 h. There were no significant differences between ASC and chlorhexidine rinses except at 30 and 60 min when significantly greater reductions were produced by 2 ASC rinses compared to the chlorhexidine rinse. Plaque indices and areas were considerably and significantly lower with the ASC and chlorhexidine rinses compared to the placebo rinse. There were no significant differences between plaque scores for the 3 ASC rinses and the chlorhexidine rinse, although for 2 ASC rinses plaque scores were lower than for the chlorhexidine rinse. The results indicate that the 3 ASC rinses have equivalent plaque inhibitory action to chlorhexidine as a rinse. Similar to chlorhexidine. the plaque inhibitory action of the rinses appears to be derived from a persistence of antimicrobial action in the mouth.     

Acid production from sorbitol in human dental plaque.

Acid production from glucose and sorbitol in dental plaque suspensions and the pH changes in dental plaque in vivo after mouth rinses with 10 per cent solutions of glucose and sorbitol were studied before and after 4–6 weeks of frequent daily mouth rinses with sorbitol in 18 subjects. The mean acid production from sorbitol, in per cent of that from glucose, increased about 21 per cent (p < 0.001) and mean initial (resting) plaque pH values were approximately 0.2 units higher (p < 0.01) after the sorbitol adaptation period. The pH-decreases from sorbitol were significantly more pronounced after the 6-week adaptation period (p < 0.01). Acid production activity from sorbitol and the pH-decreases after mouth rinses with sorbitol were considerably smaller than the corresponding values found with glucose before as well as after the adaptation period.     

A comparison of the plaque-inhibitory properties of stannous fluoride and low-concentration chlorhexidine mouthrinses

BACKGROUND: Plaque inhibition by chlorhexidine (CHX) rinses is dose related with a relatively flat dose-response curve above 5-6 mg twice daily. Low dose regimens could therefore reduce local side effects but maintain reasonable efficacy. AIMS: To compare the plaque inhibitory properties of two low-dose CHX rinse products with more conventional levels delivered from proprietary rinses. A secondary outcome was a comparison with a stannous fluoride/amine fluoride (SFAF) rinse product. METHODS: The study was a five-treatments, negative controlled, randomised, single blind crossover design balanced for residual effects, involving 20 healthy subjects in a 24-h plaque re-growth model. On day 1 of each study period, subjects were rendered plaque free, suspended tooth cleaning and followed the appropriate rinse regimen. On day 2, subjects were scored for plaque by index and area. The rinse codes and rinsing regimens were: (A) 15 mg CHX 2 x daily for 30 s (0.1% CHX), (B) 9 mg CHX 2 x daily for 60 s (0.06% CHX), (C) 10 ml SFAF rinse 1 x daily for 30 s, (D) 15 ml placebo 2 x daily for 60 s, and (E) 6 mg CHX 2 x daily for 30 s (0.06% CHX). RESULTS: Average mouth plaque indices and areas were highly significantly different between rinsing regimens. All test rinses were significantly more effective than the placebo rinse. There was a mean dose-response pattern for the CHX rinses, but there were no statistically significant differences between any of the test rinses. CONCLUSIONS: Lower doses of chlorhexidine in rinses can be used to exert plaque inhibition comparable with products used at higher doses and equivalent to benchmark products such as the SFAF rinse. However, the availability of chlorhexidine from formulations has to be considered as in part explaining the results.     

The effect of some cationic antiseptics on the acidogenicity of dental plaque in vivo

Two series of experiments were performed in order to compare the ability of different cationic antiseptics to inhibit the acid production in plaque. In addition an attempt was made to evaluate the influence of oral retention on the acid-inhibiting properties of these agents. In one series of experiments acid production, following sucrose applications on plaque, was measured in situ prior to and at given time intervals after rinsing with the individual agents. In a second series the effect of eluting the antiseptics retained in the oral cavity by means of 5 consecutive acetic acid (6 mM) rinses was evaluated. The results showed that chlorhexidine (0.5 mM) was more effective than benzalkonium chloride (1 mM) and piperazine (1 mM). Cetylpyridinium chloride (1 mM) was the least effective. Acidic elution markedly reduced the inhibitory effect of single rinses of chlorhexidine (0.5 mM), benzalkonium chloride (1 mM) and the cetylpyridinium chloride (1 mM). This effect was less pronounced with a higher concentration (2.2 mM) of chlorhexidine. The results gave support to the view that retention of an agent in the mouth and in plaque is of significance for its ability to inhibit acid production of dental plaque.     

Dose response of chlorhexidine against plaque and comparison with triclosan

Abstract The optimum dose of chlorhexidine delivered by mouthrinse, which balances efficacy against local side-effects, is generally considered to be in the region of 20 mg 2 × daily. Unfortunately, there have been few dose-response studies for chlorhexidine mouthrinses and for these, only limited details are published. The aims of this study were to determine the dose response of chlorhexidine to plaque inhibition and position a 0.1% triclosan rinse within this model. 28 subjects took part in this 7-treatment, double-blind, randomised cross-over 4-day plaque regrowth study. The rinses were 0.01%, 0.05%, 0.1% and 0.2% chlorhexidine, 0.1% triclosan and minus active controls for chlorhexidine and triclosan. On day 1 from a zero plaque baseline, volunteers suspended tooth-cleaning and commenced supervised 2 × daily rinsing with 10 ml volumes of the allocated rinses. On Day 5, plaque was scored by index and area. Treatment differences between the 7 rinses were highly significant. A clear dose-response pattern was seen for chlorhexidine with mean plaque scores decreasing with increasing dose. Even at 0.01%. chlorhexidine showed considerable and significant plaque inhibition compared to control. Triclosan at 0.1% showed limited plaque inhibition and less than 0.01% chlorhexidine. The findings of this study suggest that consideration could be given to low concentration chlorhexidine rinses as adjuncts to oral hygiene.     

Side effects of chlorhexidine mouth washes

abstract – The side effects of chlorhexidine mouth washes have been evaluated in a group of 50 soldiers during a period of 4 months. Previous publications have shown the effects on plaque formation and gingival conditions. The present paper discusses unfavorable side effects. When rinsing with 0.2 and 0.1 % chlorhexidine gluconate and acetate, some desquamations and soreness in the oral mucosa were observed. Twelve per cent of the tooth surfaces and 62 % of the silicate fillings were discolored, while 36 % of the test persons developed discolored tongues in the experimental period. Because of the side effects, there. are some objections to uncritical use of chlorhexidine in preventive dentistry. A close control is necessary; and until more information is gained, the use of chlorhexidine mouth washes is recommended for short periods only. Other methods of application must be studied.     

Effect of toothpaste on the plaque inhibitory properties of a cetylpyridinium chloride mouth rinse

BACKGROUND AND AIMS: Cetylpyridinium chloride (CPC) mouth rinses have moderate plaque inhibitory activity when used alone but rarely have shown adjunctive benefits to tooth brushing with toothpaste. Several explanations for this apparent anomaly can be proferred, including loss of antiseptic activity due to interactions with toothpaste ingredients. The aim of this study was to measure the effect of toothpaste on the plaque inhibitory properties of a CPC mouth rinse using paired rinses of CPC, toothpaste slurry (TP) and water (W). METHODS: The study was a single blind, randomised, seven-treatment, cross over design balanced for residual effects, involving 21 healthy, dentate subjects. The paired rinses were: W-CPC, CPC-W, TP-CPC, CPC-TP, W-TP, TP-W and W-W. Rinsing with solutions or slurries was done for 60 s twice per day. On day 1, subjects were rendered plaque free, suspended tooth cleaning and commenced the allocated rinse regimen. On day 5, plaque was scored by index. A 2(1/2) day wash out of normal oral hygiene was allowed between each regimen. RESULTS: The order from lowest to highest plaque scores was as follows: W-CPC = CPC-W < CPC-TP < TP-CPC < or = W-TP < TP-W < W-W. Several differences in pairs of treatments were statistically significant, the most relevant of which were significantly less plaque with W-CPC compared to TP-CPC, TP-W and W-TP, and significantly more plaque with W-W compared to all other regimens except TP-W. Conclusions: Toothpaste, whilst possessing some plaque inhibitory activity, when used immediately before a CPC mouth rinse adversely affected the plaque inhibitory action of this antiseptic. This in part may explain the reported lack of adjunctive benefits of CPC rinses to normal oral hygiene practices and supports the suggestion, made for chlorhexidine rinses, that their use should follow toothpaste by at least 60 min.     

Plaque-inhibiting effect of bioadhesive mucosal tablets containing chlorhexidine in a 4-day plaque regrowth model

BACKGROUND AND AIM: Compliance in the use of daily oral antiseptics can probably be enhanced by prescribing easily-applied bioadhesive tablets which slowly release chlorhexidine (CHX). This could also be of use in patients with difficulties in rinsing or performing mechanical plaque control. The aim of the present study was to evaluate the capacity of bioadhesive tablets containing either 30 mg or 40 mg of CHX to inhibit de novo plaque formation. METHOD: In this single, examiner-blinded, crossover study, 22 volunteers between 21 and 25 years of age refrained from oral hygiene for 4 days. Bioadhesive mucosal tablets containing 30 mg or 40 mg of CHX were applied in the canine region. Rinses with a 0.2% CHX solution and placebo tablets served as controls. Plaque regrowth was evaluated with the Quigley-Hein Index modification of Turesky and by an automatic image analysis system (AIA) using slides of stained plaque. Rinsing and application of the tablets were done under supervision twice daily. RESULTS: According to the plaque index, plaque regrowth was significantly inhibited by CHX rinses ( P<0.001) and by tablets with 40 mg of CHX ( P<0.02) for all teeth and surfaces. Placebo tablets and 30-mg CHX tablets had no plaque-inhibiting effect. For taste, the subjects preferred the placebo and the 30-mg tablets more than the rinses and 40-mg tablets. In 3/22 of the subjects, superficial mucosal lesions were found at the side of application of the 40-mg tablets. Using the AIA system for evaluation of plaque regrowth, similar results for plaque inhibition were found. CONCLUSION: It can be concluded that bioadhesive mucosal tablets containing 40 mg of CHX can inhibit plaque regrowth as well as 0.2% CHX rinses. However, unpleasant taste and superficial mucosal lesions are local side effects to be considered.     

Comparison of plaque accumulation after topical application and mouth rinsing with chlorhexidine gluconate

This study measured plaque accumulation on anterior teeth after topical or mouth rinse application of 0.2% chlorhexidine gluconate. Compared with water plaque scores were highly significantly reduced. There was no significant difference in plaque scores between topical application or mouth rinsing. The importance of locally adsorbed chlorhexidine is emphasised and the relevance of an oral reservoir effect questioned.     

The effects of an essential oil and an amine fluoride/stannous fluoride mouthrinse on supragingival plaque regrowth

BACKGROUND: The side effects of chlorhexidine (CHX) have stimulated the search for alternative antiplaque agents such as amine fluoride/stannous fluoride (ASF) and essential oils (EO). The aim of the study was to investigate the plaque-inhibiting effects of two commercially available mouthrinses containing ASF and EO, respectively. METHODS: The study was an observer-masked, randomized, 5 x 5 Latin square cross-over design, balanced for carryover effects, involving 15 volunteers in a 4-day plaque regrowth model. A 0.12% CHX rinse and a saline solution served as positive and negative controls, respectively. On day 1, subjects received professional prophylaxis, suspended oral hygiene measures, and commenced rinsing with their allocated rinses. On day 5, subjects were scored for disclosed plaque. The ASF rinse was tested at two dosages: 10 and 20 ml (ASF-10 and ASF-20, respectively). RESULTS: The ASF and EO rinses showed a significant inhibition of plaque regrowth compared to saline (P <0.0001), but the lowest plaque indices were obtained with the CHX product (P <0.01). There were no significant differences among products containing ASF-10, ASF-20, and EO (P >0.05). There was no correlation between the occurrence of side effects and the use of a particular rinse product (P >0.2). CONCLUSIONS: ASF and EO mouthrinses exerted effective and similar plaque inhibition. The two dosages tested for ASF did not differ in plaque reduction. These findings, together with those from long-term trials, suggest that ASF and EO rinses may represent effective alternatives to CHX rinse as adjuncts to oral hygiene.     

Comparative evaluation of efficacy of sodium fluoride, chlorhexidine and triclosan mouth rinses in reducing the mutans streptococci count in saliva : an in vivo study

The primary objective of this study was to compare the efficacy of sodium fluoride (0.05%), chlorhexidine (0.12%) and triclosan (0.3%) mouth rinses in reducing the mutans streptococci count in saliva. 60 subjects in the age group of 12 to 14 years were selected from the schools of Mumbai and were equally divided into 4 groups. First 3 groups were test groups and the 4th group was control group. The subjects were instructed to rinse one full marked measure of mouth rinse for 1 minute, twice daily. Salivary samples were collected at baseline and after 2 weeks and cultured on M.S.B.agar. The number of mutans streptococci colonies were counted on agar medium. The results of the study confirmed that chlorhexidine mouth rinses are more efficient in reducing mutans streptococci count in saliva as compared to other mouth rinses.     

A simple approach to examine early oral microbial biofilm formation and the effects of treatments

BACKGROUND/AIMS: A simple in vivo approach to examine early dental plaque formation in the human mouth and to determine the effects of common dietary and oral hygiene procedures on biofilm formation is reported. METHODS: A custom designed device that fits securely behind the teeth of the mandibular arch provides a surface for microbial colonization. This device is prepared with denture acrylic and can be repeatedly used by the subject, exposing a large and constant surface area for microbial accumulation. RESULTS: Large numbers of oral bacteria colonized the device by 2 h; these increased significantly by 4 h (P < 0.05). Bacterial colonization increased significantly after rinsing with a sucrose solution (P < 0.05) but remained unaffected after rinsing with water, a commercially available fluoride mouthrinse without antimicrobial agents, or brushing with a fluoride dentifrice (P > 0.05). Rinsing with mouthrinses formulated with chlorhexidine, cetylpyridinium chloride or triclosan/copolymer significantly inhibited colonization (P < 0.05). A dose-dependent inhibition was noted with chlorhexidine rinses (P < 0.05). Brushing with a triclosan/copolymer dentifrice significantly inhibited microbial colonization compared with a control (P < 0.05). CONCLUSION: This simple approach was useful for examining the effects of common dietary and oral hygiene procedures. Significant biofilm inhibitory effects were noted with formulations that demonstrated efficacy in previous clinical studies.     

A randomized clinical trial on the short-term clinical and microbiological effects of the adjunctive use of a 0.05% chlorhexidine mouth rinse for patients in supportive periodontal care

OBJECTIVE: To evaluate the clinical and microbiological activity of a new mouth rinse formulation, used as an adjunct to oral hygiene, for patients in supportive periodontal care. PATIENTS AND METHODS: This was a randomized, placebo-controlled clinical trial with two groups: test group, rinsing twice per day with the test product (with 0.05% chlorhexidine and 0.05% cetylpyridinium chloride); and control group, rinsing with a placebo. Treated chronic periodontitis patients were included, and two visits were rendered, baseline, and after 15 days. Clinical outcome variables included plaque and gingival indices, and probing pocket depth. Subgingival samples were processed by culturing. Patient-based variables and adverse effects were also assessed. Outcome variables were compared by t-test, chi2, and Mann-Whitney test. RESULTS: The results belonged to 33 patients. Plaque and gingival indices, and the log of bacterial total counts were reduced in the test group (p < or = 0.01), but differences between groups were only statistically significant (p < 0.05) for plaque and bacterial counts. A significant reduction in the proportions of flora (p < 0.05) and frequency of detection (p = 0.01) of Porphyromonas gingivalis was observed in the test group. CONCLUSIONS: The newly formulated mouth rinse demonstrated short-term plaque-inhibitory activity. This was associated with a reduction in the total load of anaerobic subgingival microflora.