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At least 217 records · Page 12Linked to original sources

PubMed2006

A comparison of two chlorhexidine gel brushing regimens and a conventional toothpaste brushing regimen for the development of tooth staining over a 6-week period.

AIMS: A single-centre, randomized single-blind parallel study was undertaken to compare staining seen with three brushing regimens and to determine subject perception of side effects such as staining and effects on taste. METHODS: This 6-week parallel study used 157 volunteers who were randomized into one of three treatment groups: (i) brushing in the morning and evening with a normal dose of a 1% chlorhexidine gel, (ii) brushing with a low dose of chlorhexidine gel in the evening and a whitening dentifrice in the morning, and (iii) brushing with a standard fluoride paste in the morning and evening. Following home usage of their allocated products, the study volunteers returned after 3 and 6 weeks to record the amount of stain present. After the 6-week period, subject perception of taste and stain acceptability was determined using a questionnaire. RESULTS: After 6 weeks of use of the low-dose chlorhexidine gel and whitening dentifrice, significantly more stain was seen compared with the use of a standard dentifrice (P<0.0001). Similarly, significantly more stain was seen with use of the normal-dose chlorhexidine gel compared with the low-dose gel and whitening dentifrice (P=0.0007). Approximately 30% of individuals on the low-dose chlorhexidine gel regimen found the amount of stain unacceptable and 10% noted an effect on their taste perception. CONCLUSIONS: The use of low dose of chlorhexidine gel at night and a whitening paste in the morning produced a significant amount of stain that 30% of subjects considered unacceptable.

Adult↗

PubMedDate not supplied

Efficacy of chlorhexidine swabbing in oral health care for people with severe disabilities.

Chlorhexidine is effective when used as an oral rinse, but many disabled people cannot use such a protocol. A double-blind cross-over study tested the efficacy of applying chlorhexidine with a sponge-swab, in a sample of 76 severely disabled adults, drawn from diverse rehabilitation settings. Two randomly assigned groups applied 10 mL 0.12% chlorhexidine gluconate (Peridex, Procter & Gamble) or 10 mL placebo, using a "Toothette" (Halbrand) once daily, 5 times per week for 10 weeks. All subjects received 10 mL 0.05% NaF, applied similarly but separately from the test/placebo agent. Pre- and post-trial measures included perceived level of function and oral status, that is, DMFS, plaque, calculus, pocket depth, and tooth stain. The protocol received high levels of compliance and acceptance. Compared with placebo, swabbing with chlorhexidine resulted in consistent, and, in part, significant improvements in plaque, gingivitis, and periodontal pocket depth. Side effects of chlorhexidine, that is, tooth stain and calculus, were relatively minor. Perceived improvements in dental health were associated with improved physical health, appearance, and mouth odor. The results indicate that chlorhexidine swabbing is a useful oral disease preventive protocol for persons with disability.

Adult↗

PubMed1993

[In vitro induction of chlorhexidine- and benzalkonium-resistance in clinically isolated Pseudomonas aeruginosa].

A study was made on the MIC distributions of chlorhexidine and benzalkonium chloride against clinically isolated 178 strains of Pseudomonas aeruginosa to find out the existence of strains resistant to those disinfectants and also on the in vitro induction of resistance to both drugs. The MIC of chlorhexidine gluconate was found to be distributed from 78 to 625 micrograms/ml with a single peak at 312 micrograms/ml. All 178 strains of clinical isolates were sensitive to chlorhexidine and none could be induced to become chlorhexidine resistant in vitro, suggesting that P. aeruginosa can not easily acquire chlorhexidine resistance. On the other hand, the MIC of benzalkonium chloride was distributed in two peaks; one peak was benzalkonium sensitive at 625 micrograms/ml (150 strains/178 strains: 84.3%) and the another peak was benzalkonium resistant at 5,000 micrograms/ml (28 strains/178 strains; 15.7%). Six (4.0%) of the 150 benzalkonium sensitive strains acquired benzalkonium resistance by in vitro induction of resistance; the MIC of 5 strains increased from 625 micrograms/ml to 2,500 micrograms/ml and that of the residual 1 strain increased from 312 micrograms/ml to 1,250 micrograms/ml. However, no change of MIC was observed in 28 benzalkonium-resistant strains of clinically isolated P. aeruginosa by in vitro resistance induction. Strains with MIC more than 5,000 micrograms/ml could not be obtained at all. The results suggest that the benzalkonium resistance can be introduced in P. aeruginosa whereas the resistance-acquiring rate is low. These results suggest that chlorhexidine gluconate is the first choice for prevention of Pseudomonas infection in the hospital and benzalkonium is also useful in 0.5% solution is used.

Aerosols↗

PubMed1976

Effect of antimicrobial soap containing chlorhexidine on the microbial flora of skin.

The qualitative and semiquantitative changes in the aerobic microbial flora of normal skin with the prolonged use of a chlorhexidine scrub (6 months) were investigated. More samples in the chlorhexidine scrub group had gram-negative bacilli in their axilla (63 of 96, 66%) and groin (36 of 96, 38%) than the controls (32 of 66, 49%, for axilla and 7 of 66, 11%, for groin; P = 0.01). Klebsiella and Enterobacter were the predominant organisms in the control and chlorhexidine groups, respectively. The chlorhexidine scrub produced a reduction in the total aerobic counts in the axilla, groin, and between the toes and the fingers. Fewer samples from the chlorhexidine-treated areas revealed the presence of lipophilic diphtheroids than did the controls. Lipophilic diphteroids were also reduced quantitatively in the groin and axilla with chlorhexidine treatment. No consistent pattern for the other major groups of bacteria was noted between the treatments.

Aerobiosis↗

PubMed1993

Adaptation and growth of Serratia marcescens in contact lens disinfectant solutions containing chlorhexidine gluconate.

Serratia marcescens (11 of 12 strains) demonstrated an ability to grow in certain chlorhexidine-based disinfecting solutions recommended for rigid gas-permeable contact lenses. For a representative strain, cells that were grown in nutrient-rich medium, washed, and inoculated into disinfecting solution went into a nonrecoverable phase within 24 h. However, after 4 days, cells that had the ability to grow in the disinfectant (doubling time, g = 5.7 h) emerged. Solutions supporting growth of S. marcescens were filter sterilized. These solutions, even after removal of the cells, showed bactericidal activity against Pseudomonas aeruginosa and a biphasic survival curve when rechallenged with S. marcescens. Adaptation to chlorhexidine by S. marcescens was not observed in solutions formulated with borate ions. For chlorhexidine-adapted cells, the MIC of chlorhexidine in saline was eightfold higher than that for unadapted cells. Cells adapted to chlorhexidine showed alterations in the proteins of the outer membrane and increased adherence to polyethylene. Cells adapted to chlorhexidine persisted or grew in several other contact lens solutions with different antimicrobial agents, including benzalkonium chloride.

Adaptation, Biological↗

PubMed1998

Randomised trial of 0.2% chlorhexidine gluconate and 2.5% natamycin for fungal keratitis in Bangladesh.

AIM: The management of suppurative keratitis due to filamentous fungi presents severe problems in tropical countries. The aim was to demonstrate the efficacy of chlorhexidine 0.2% drops as an inexpensive antimicrobial agent, which could be widely distributed for fungal keratitis. METHODS: Successive patients presenting to the Chittagong Eye Institute and Training Complex with corneal ulcers were admitted to the trial when fungal hyphae had been seen on microscopy. They were randomised to drop treatment with chlorhexidine gluconate 0.2% or the standard local treatment natamycin 2.5%. The diameters, depths, and other features of the ulcers were measured and photographed at regular intervals. The outcome measures were healing at 21 days and presence or absence of toxicity. If there was not a favourable response at 5 days, "treatment failure" was recorded and the treatment was changed to one or more of three options, which included econazole 1% in the latter part of the trial. RESULTS: 71 patients were recruited to the trial, of which 35 were randomised to chlorhexidine and 36 to natamycin. One allocated to natamycin grew bacteria and therefore was excluded from the analysis. None of the severe ulcers was fully healed at 21 days of treatment, but three of those allocated to chlorhexidine eventually healed in times up to 60 days. Of the nonsevere ulcers, 66.7% were healed at 21 days with chlorhexidine and 36.0% with natamycin, a relative efficacy (RE) of 1.85 (CL 1.01-3.39, p = 0.04). If those ulcers were excluded where fungi were seen in the scraping but did not grow on culture, the estimated efficacy ratio does not change but becomes less precise because of smaller numbers. Equal numbers of Aspergillus (22) and Fusarium (22) were grown. The Aspergillus were the most resistant to either primary treatment. CONCLUSIONS: Chlorhexidine may have potential as an inexpensive topical agent for fungal keratitis and warrants further assessment as a first line treatment in situations where microbiological facilities and a range of antifungal agents are not available.

Adolescent↗

PubMedDate not supplied

Effect of chlorhexidine varnish and gel on mutans streptococci in margins of restorations in adults.

The aim of this study was to compare the effect of two different chlorhexidine regimens, varnish and gel, on mutans streptococci (MS) in the margins of restorations and in saliva. Eighteen subjects (mean age 44 years) with >250,000 MS/ml saliva and with many restored teeth were assigned to three groups, each comprising 6 individuals. They were treated with: (1) Cervitec varnish, containing 1% chlorhexidine and 1% thymol; (2) placebo varnish, or (3) Corsodyl gel, containing 1% chlorhexidine. The varnish was applied on two separate occasions to all tooth surfaces at an interval of 3-4 days. The gel was applied for 3 x 5 min in individual applicators on 2 consecutive days. Plaque samples from 8-9 margins of restorations per subject, mainly in the premolar and molar region, and stimulated saliva samples were collected at baseline and after 1, 4, 8 and 12 weeks. The general finding was that the Corsodyl gel gave the most pronounced reduction of MS followed by the Cervitec varnish. According to repeated measures ANOVA, no significant differences could be demonstrated either for MS in margins or in saliva among the three groups (p = 0.06 for margins and p = 0.07 for saliva). However, within the groups, the reduction of MS over time was statistically significant, both in margins and in saliva (p < 0.001 and p < 0.05, respectively). Student-Newman-Keuls test showed that MS in margins were significantly reduced at most sampling occasions in both chlorhexidine groups: the reduction was more pronounced in the Corsodyl gel group. The conclusion from this study is that the 1% chlorhexidine gel Corsodyl, administered 6 times during 2 days, is more effective in suppressing MS in the margins of restorations and in saliva than the 1% chlorhexidine varnish Cervitec, administered twice within 3-4 days.

Adult↗

PubMedDate not supplied

The effect of 6-monthly application of 40% chlorhexidine varnish on the microflora and dental caries incidence in a population of children in Surinam.

This study is aimed at determining whether a commercially available varnish, containing 40% chlorhexidine, is able to reduce the numbers of mutans streptococci and lactobacilli in saliva, in a moderately caries-active population in Surinam. 238 children, ages 13-14 years, were selected from different schools in Paramaribo, Surinam. From these children, total dental status was recorded and saliva samples were taken. At baseline and every 6 months, a 40% chlorhexidine varnish (EC40) was applied. The control group received a neutral gel that did not contain chlorhexidine. The numbers of salivary mutans streptococci and lactobacilli were calculated by standard methods, and the caries status was recorded every 12 months. The study lasted 30 months. The results indicate that chlorhexidine varnish did not decrease the numbers of cariogenic bacteria, nor did it decrease caries progression. Moreover, in this population with a low dental health care, children with lactobacilli present in the saliva above our detection level, the chlorhexidine varnish even tended to increase caries progression, possibly due to selection of aciduric and acidogenic oral bacterial species. We therefore conclude that 40% chlorhexidine varnish is not likely to decrease caries in children in a high-treatment-need population without treatment of the sources of infection.

Adolescent↗

PubMed1994

Effect of chlorhexidine varnish on streptococci in dental plaque from occlusal fissures.

The treatment of tooth surfaces with chlorhexidine varnish may lead to long-lasting suppression of mutants streptococci in dental plaque. Microbiological observations following varnish treatment suggest that this prolonged suppression might be caused by bacterial interference. To investigate whether physiologically related organisms, such as other Streptococcus species, compete with mutans streptococci in the ecosystem, we have analyzed streptococcal populations on the tooth surface before and after chlorhexidine varnish treatment. Occlusal surfaces with high numbers of mutans streptococci were selected in human volunteers and treated with chlorhexidine varnish. Analyses of sequentially collected plaque samples confirmed that S. oralis-group streptococci returned to baseline levels shortly after the chlorhexidine application, while Actinomyces naeslundii populations reached prestudy or even higher levels only several days after treatment. Mutans streptococci, however, were below the detection level in the 14-day samples, except in 1 individual. The pattern of recolonization by individual Streptococcus species after chlorhexidine application closely resembled that of cleaned enamel surfaces: S. oralis and S. sanguis were primary colonizers while S. gordonii became dominant at a later stage. It is concluded that after intensive chlorhexidine treatment, a normal oral microflora reestablished, characterized by low proportions of mutans streptococci.

Actinomyces↗

PubMedDate not supplied

The effects of chlorhexidine irrigation solution on contaminated bone-tendon allografts.

The purpose of this study was to determine an expedient and effective method for disinfecting contaminated human bone-tendon allografts. The first part of this study used beef muscle and cadaveric human tissues to determine the most effective solution and volume to decontaminate tissues inoculated with four different organisms: Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, and Klebsiella pneumoniae. Of the solutions tested (benzalkonium chloride, castile soap, castile soap followed by benzalkonium chloride, triple antibiotic, chlorhexidine gluconate, and chlorhexidine gluconate/triple antibiotic), only the 4% chlorhexidine power irrigation solution and 4% chlorhexidine/triple antibiotic bath completely disinfected all tissues. Work in part 2 revealed that a 2% chlorhexidine irrigation solution was equally effective as the 4% solutions. Part 3 of the study involved human Achilles tendon-calcaneus allografts. We found similar results: 3 liters of 2% chlorhexidine power irrigation solution thoroughly removed all microorganisms from the contaminated tissues. All control allografts irrigated with normal saline solution alone revealed positive bacterial growth for all four organisms after 72 hours' growth on sheep blood agar. Total decontamination time was 10 to 12 minutes. Two percent chlorhexidine irrigation solution may be an effective method for decontaminating human bone-tendon allografts challenged with a polymicrobial inoculum. This method of disinfecting bone-tendon allografts is at least five times more expeditious than methods in previously reported studies.

Animals↗

PubMedDate not supplied

Preoperative gentamicin eye drops and chlorhexidine solution in cataract surgery. Experimental and clinical results.

PURPOSE: 1) To evaluate the effects on the conjunctival flora of gentamicin ophthalmic eye drops 0.3%, given four times in 45 minutes, and a conjunctival rinse with 10 ml chlorhexidine 0.05% solution. 2) To investigate retrospectively the rate of endophthalmitis after cataract operations when these antimicrobials were applied preoperatively. METHODS: Seventy-six patients undergoing standard phacoemulsification operations were enrolled in the experimental part of the study. Cultures were taken preoperatively, 5 minutes after prophylaxis with either chlorhexidine or gentamicin. To assess the combined effects of chlorhexidine and gentamicin, cultures were taken after the cataract operation. Hospital charts were reviewed for cases of endophthalmitis in 1994 and 1995, when this prophylactic protocol was used at the St Erik's cataract surgery department. RESULTS: The conjunctival microflora was significantly suppressed by chlorhexidine rinsing alone (p = 0.001), while no other significant anti-bacterial effects were observed with the experimental prophylaxis. The endophthalmitis rate was 32/12. 806 operations (0.25%). CONCLUSIONS: Topical rinsing with chlorhexidine solution suppresses conjunctival flora in the short term. Combined topical chlorhexidine and gentamicin prophylaxis does not eliminate postoperative endophthalmitis caused by gram-positive bacteria.

Adult↗

PubMed2007

Chlorhexidine preserves dentin bond in vitro.

Loss of hybrid layer integrity compromises resin-dentin bond stability. Matrix metalloproteinases (MMPs) may be partially responsible for hybrid layer degradation. Since chlorhexidine inhibits MMPs, we hypothesized that chlorhexidine would decelerate the loss of resin-dentin bonds. Class I preparations in extracted third molars were sectioned into two halves. One half was customarily restored (etch-and-rinse adhesive/resin composite), and the other was treated with 2% chlorhexidine after being acid-etched before restoration. Specimens were stored in artificial saliva with/without protease inhibitors. Microtensile bond strengths and failure mode distribution under SEM were analyzed immediately after specimens' preparation and 6 months later. With chlorhexidine, significantly better preservation of bond strength was observed after 6 months; protease inhibitors in the storage medium had no effect. Failure analysis showed significantly less failure in the hybrid layer with chlorhexidine, compared with controls after 6 months. In conclusion, this in vitro study suggests that chlorhexidine might be useful for the preservation of dentin bond strength.

Acid Etching, Dental↗

PubMed1994

Randomized trial of a chlorhexidine mouthwash for alleviation of radiation-induced mucositis.

PURPOSE: To determine whether a chlorhexidine mouthwash could alleviate radiation-induced oral mucositis. PATIENTS AND METHODS: Patients scheduled to receive radiation therapy to include greater than one third of the oral cavity mucosa were selected for study. Following stratification, they were randomized in a double-blind manner to receive a chlorhexidine mouthwash or a placebo mouthwash. Both groups were then similarly evaluated for mucositis and mouthwash toxicity. RESULTS: Twenty-five patients were randomized to receive the chlorhexidine mouthwash, while 27 received the placebo mouthwash. Treatment arms were well balanced. There was a trend for more mucositis and there was substantially more toxicity (eg, mouthwash-induced discomfort, taste alteration, and teeth staining) on the chlorhexidine arm. CONCLUSION: In contrast to the prestudy hypothesis that a chlorhexidine mouthwash might provide benefit for patients receiving radiation therapy to the oral mucosa, this study provides strong evidence suggesting that a chlorhexidine mouthwash is detrimental in this clinical situation.

Aged↗

PubMed1989

Comparison of chlorhexidine delivery by mouthwash and spray on plaque accumulation.

The delivery of chlorhexidine by spray systems have been found useful in controlling plaque in handicapped individuals. This study using a single blind crossover design compared chlorhexidine delivery by mouthwash and spray for plaque inhibitory effects. A group of 14 volunteers participated in two 4 day, no oral hygiene regimens. During one regimen chlorhexidine was professionally sprayed onto the teeth twice a day and during the other chlorhexidine was rinsed twice a day under supervision. Plaque regrowth from a zero baseline was recorded using a plaque index and by area. Little plaque accumulated during the two periods. There was no significant difference in plaque measurements following the use of the spray or mouthwash. This study demonstrated that chlorhexidine when sprayed under optimal conditions was as effective as a mouthwash at controlling plaque despite only requiring one seventh of a dose from a rinse. The results have implications for the use and delivery of chlorhexidine for plaque control and are relevant to the proposed mode of action of this antiseptic.

Adult↗

PubMed1989

The use of 0.2% chlorhexidine spray as an adjunct to oral hygiene and gingival health in physically and mentally handicapped adults.

Chlorhexidine has been used as an aid to or replacement for oral hygiene measures in special needs groups such as the handicapped. Previous studies have indicated that spray delivery of chlorhexidine is both effective and acceptable. This study evaluated twice daily use of a 0.2% chlorhexidine spray as an adjunct to toothbrushing in a group of physically and mentally handicapped adults attending a day training center. The study was a double-blind, placebo controlled, cross-over design involving two 31 days regimens separated by 30 days. Plaque, bleeding on probing, and pocketing were measured at the beginning and end of each regimen. There were clinically and statistically significantly lower plaque and bleeding scores at the end of the chlorhexidine compared to the placebo period. Pocketing was also significantly less after chlorhexidine, although in clinical terms the difference was small. The apparent acceptability and effectiveness of the regimen suggests that small doses of chlorhexidine delivered by sprays may be of considerable value as an aid to oral hygiene in handicapped individuals.

Adult↗

PubMed1990

Irrigation with 0.06% chlorhexidine in naturally occurring gingivitis. II. 6 months microbiological observations.

In an examiner blind positive/negative controlled 6-month study, the efficacy of supragingival irrigation with 0.06% chlorhexidine gluconate on the marginal and subgingival microflora in naturally occurring gingivitis was evaluated. The 222 patients enrolled in the study were assigned to one of four groups: Group 1: Once daily irrigation with 300 ml water followed by irrigation with 200 ml 0.06% chlorhexidine gluconate (experimental); Group 2: Twice daily rinsing with 15 ml 0.12% chlorhexidine (positive control); Group 3: Once daily irrigation with 500 ml water (irrigation control) and Group 4: Sodium fluoride dentifrice for normal oral hygiene only (negative control). All groups received the same sodium fluoride dentifrice for tooth brushing. All patients received a supra- and subgingival oral prophylaxis after baseline examination and at the end of the investigation. Plaque samples were analyzed from 105 patients at baseline, 93 patients at 3 months and 88 patients at 6 months. The 6-months results demonstrated that, when compared with tooth brushing alone, adjunctive supragingival irrigation with 0.06% chlorhexidine gluconate was most effective by significantly reducing (P less than or equal to 0.008) both log10 CFU and % of Gram-negative anaerobic rods and black-pigmented Bacteroides. Chlorhexidine rinse also significantly (P less than or equal to 0.008) reduced log10 CFU of black-pigmented Bacteroides at 6 months. Both chlorhexidine regimens significantly (P less than or equal to 0.008) increased the % of Gram-positive facultative cocci compared to water irrigation at 3 months. Water irrigation had a limited effect on any of the assessed bacterial groups (log10 CFU and %).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1991

The effect of chlorhexidine treatment of root surfaces on the attachment of human gingival fibroblasts in vitro.

Chlorhexidine mouthrinse is a widely used adjunct in periodontal therapy due to its bactericidal effects. The effect of this agent on chronic gingivitis and wound healing following surgical therapy in animals and humans has been favorable. The re-establishment of lost connective tissue attachment to the root surface following periodontal therapy is a desirable goal in which the ability of periodontal ligament fibroblasts to reattach to root surfaces of periodontally involved teeth is a critical event. Understanding the effect of chlorhexidine on fibroblast attachment will provide the rationale for its use during the healing phase of periodontal surgery. For this study, impacted third molars were sectioned into 4 pieces. Groups of 10 root pieces were exposed to 0.12% chlorhexidine or saline for 3 minutes followed by a distilled water rinse. The root pieces were incubated with human gingival fibroblasts (HGF) using standard tissue culture techniques for 1, 2, 4, 6, and 8 hours. HGF were prelabeled with 3H-thymidine to a standard specific activity. The surface area of each root piece was determined and the attached cells quantified by using scintillation spectroscopy. The number of cells per unit area was then calculated and the data expressed as cells/mm2. The repeated measures design was statistically analyzed by repeated measures analysis of variance. There was a significant difference between the number of attached cells in the chlorhexidine and the control groups (P less than 0.001). Exposure of root surfaces to chlorhexidine significantly inhibits subsequent fibroblast attachment which may interfere with regeneration of the periodontium. Hence, the data suggest that efforts should be made to minimize chlorhexidine contact with the root surface with physical barriers.

Cell Adhesion↗

PubMed1993

Retention of antimicrobial activity by human root surfaces after in situ subgingival irrigation with tetracycline HCl or chlorhexidine.

Substantivity of tetracycline HCl and chlorhexidine digluconate was assessed in extracted teeth. Fifty periodontally compromised teeth scheduled for extraction with probing depths ranging between 6 and 12 mm were root planed and then irrigated in situ with 1 of 4 solutions: tetracycline HCl at concentrations of 10 or 50 mg/ml, 0.12% chlorhexidine digluconate, or 0.9% sterile saline. Each tooth was exposed to 150 ml of the respective irrigation solution. Following extractions, the teeth were transferred to tris buffered saline and incubated at room temperature for 22 days. Incubation solutions were replaced at 24-hour intervals. Removed solutions were examined for desorbed antimicrobial activity using a microtiter assay in which bacterial growth was evaluated by optical density readings. Tetracycline HCl 50 mg/ml exhibited significantly greater antimicrobial activity than chlorhexidine digluconate for 12 days and greater than saline for 16 days. Tetracycline HCl 10 mg/ml exhibited significantly greater antimicrobial activity than chlorhexidine digluconate and saline for 4 days. Chlorhexidine digluconate did not exhibit any significant antimicrobial activity at any time point. Our findings demonstrate long-lasting substantivity of tetracycline HCl, but not chlorhexidine digluconate, by teeth exposed to a single episode of pocket irrigation of their periodontally-exposed roots. The amount of antimicrobial activity retained is proportional to the concentration of tetracycline HCl used for irrigation.

Adsorption↗