In vitro antimicrobial efficiency of a mouthwash containing triclosan/gantrez and sodium bicarbonate.

Braz Oral Res. 2007;21(4):342-347

Authors: Pires JR, Rossa Junior C, Pizzolitto AC

Several antiseptic substances have been used as adjuncts to routine mechanical procedures of oral hygiene, based on their antimicrobial effects. The objective of this study was to assess in vitro the antimicrobial efficiency of a mouthwash containing Triclosan/Gantrez and sodium bicarbonate in comparison to both positive and negative controls. Standard strain samples of Escherichia coli, Pseudomonas aeruginosa, Actinomyces viscosus and Bacillus subtilis were used. Samples of Streptococcus mutans and Gram-negative bacilli were collected from 20 volunteers (10 with a clinically healthy periodontium and 10 presenting biofilm-associated gingivitis). Evaluation of the antimicrobial activity was performed by determining the minimal inhibitory concentration (MIC). The results indicated that the test solution inhibited the growth of both Gram-negative and Gram-positive microorganisms from the volunteers saliva as well as that of the standard strains at the MIC dilution of 1:20, whereas the MIC dilution of 0.12% chlorhexidine against the same bacteria was 1:80. Thus, even though the tested mouthrinse solution presented an in-vitro antimicrobial activity superior to that of a placebo, it was inferior to that of chlorhexidine.

PMID: 18060262 [PubMed - as supplied by publisher]

In vitro antimicrobial activity of irreversible hydrocolloid impressions against 12 oral microorganisms.

Braz Oral Res. 2007;21(4):323-329

Authors: Casemiro LA, Pires-de-Souza FD, Panzeri H, Martins CH, Ito IY

This study evaluated in vitro the antimicrobial activity of irreversible hydrocolloids (one containing an antimicrobial agent) prepared with water or with a 0.2% chlorhexidine digluconate solution against 12 strains of the oral microbiota. Twenty specimens (0.5 x 1.0 cm) for each group (1. Jeltrate mixed with water; 2. Jeltrate mixed with 0.2% chlorhexidine digluconate solution; 3. Greengel mixed with water; 4. Greengel mixed with 0.2% chlorhexidine digluconate solution) were prepared under sterile conditions and placed in culture media inoculated with the indicator strains. After incubation in aerobiosis or microaerophilia, inhibition of the microbial growth was measured and the results were interpreted. The normal adherence curve revealed a non-normal distribution of the data, so the non-parametric Friedman Test was performed (p < 0.05). The antimicrobial activity of the groups was classified in the following order: 1, 3, 4, and 2. The results suggest that the method of preparing irreversible hydrocolloids with a 0.2% digluconate chlorhexidine solution is more effective than the incorporation of an antimicrobial agent in the powder to reduce cross-contamination caused by impressions.

PMID: 18060259 [PubMed - as supplied by publisher]

In vitro evaluation of the effectiveness of the chemomechanical preparation against Enterococcus faecalis after single- or multiple-visit root canal treatment.

Braz Oral Res. 2007;21(4):308-313

Authors: Gurgel-Filho ED, Vivacqua-Gomes N, Gomes BP, Ferraz CC, Zaia AA, Souza-Filho FJ

The purpose was to assess the elimination of Enterococcus faecalis in vitro in human mandibular premolars after chemomechanical preparation with or without the use of a calcium hydroxide dressing. After 60 days of contamination with E. faecalis, the root canals were prepared using the Crown-Down technique combined with 2% chlorhexidine gel irrigation. Then, the specimens were divided into two experimental groups, treated in a single visit or in multiple visits, and two control groups. The multiple-visit group received a dressing with calcium hydroxide for 14 days (CalenTM) and the single-visit group did not receive any medication. In the two control groups, the canals were filled with BHI after chemomechanical preparation with 2% chlorhexidine gel or distilled water. Microbial samples were taken from the root canals for colony forming unit count for each phase of the treatment using sterile paper points inside the root canal lumen. Data were ranked and analyzed by the Kruskal-Wallis statistical test. The residual microbial colonies were then assessed. The results showed that chemomechanical preparation using 2% chlorhexidine gel with no intra-canal dressing reduced by 100% the E. faecalis contamination of the root canal lumen. The calcium-hydroxide group that received the 14-day intra-canal dressing allowed a small number of bacteria to grow between visits, but without statistical differences between groups.

PMID: 18060256 [PubMed - as supplied by publisher]

Inhibitory activity of garlic (Allium sativum) extract on multidrug-resistant Streptococcus mutans.

J Indian Soc Pedod Prev Dent. 2007 Oct-Dec;25(4):164-8

Authors: Fani MM, Kohanteb J, Dayaghi M

Garlic ( Allium sativum ) extract has been known to have inhibitory activity on various pathogenic bacteria, viruses and fungi. The objective of present investigation was to study in vitro inhibitory activity of garlic extract on multidrug-resistant (MDR) strains of Streptococcus mutans isolated from human carious teeth. Filter sterilized aqueous extract of garlic was prepared and used in the present study. For isolation of S. mutans , extracted human carious teeth were cultured in Todd-Hewit broth and Mitis-Salivarius-Bacitracin agar. S. mutans was characterized by colony morphology, biochemical tests and other conventional bacteriological procedures. Disk sensitivity tests and broth dilution methods were used to determine antibiotic sensitivity profile and inhibitory activity of garlic extract on S. mutans isolated from carious teeth. Of 105 carious teeth tested, 92 (87.6%) isolates of S. mutans were recovered, among which 28 (30.4%) were MDR since they were resistant to four or more antibiotics. The highest rate of resistance was observed for tetracycline (30.4%) and least resistance (0%) to teichoplanin and vancomycin while 22.8% and 23.9% of the isolates were resistant to penicillin and amoxicillin, respectively. Chlorhexidine minimum inhibitory concentration (MIC) for MDR and non-MDR S. mutans varied from 2 to 16 microg ml-1 and from 0.25 to 1 microg ml-1 , respectively ( P S. mutans were sensitive to garlic extract with the MIC ranging from 4 to 32 mg ml-1 . Considering in vitro data obtained in the present study, mouthwashes or toothpaste containing optimum concentration of garlic extract could be used for prevention of dental caries.

PMID: 18007101 [PubMed - in process]

A comparative study of two mouthrinses on plaque and gingivitis in school children in the age group of 13-16 years in Bangalore city.

J Indian Soc Pedod Prev Dent. 2007 Jul-Sep;25(3):126-9

Authors: Jayaprakash K, Veeresha KL, Hiremath SS

Research and clinical evidence indicate that most forms of plaque associated periodontal disease start as inflammatory lesions of the gingiva which if left untreated, may progress and eventually involve and compromise the entire periodontal attachment apparatus of the affected teeth. A study was conducted to assess the effect of a mouthrinse containing chlorhexidine and sodium fluoride on plaque accumulation and gingivitis in comparison with a chlorhexidine mouthrinse alone in a group of school children aged 13-16 years in Bangalore city. This combination along with the well established effect of fluoride in the prevention of caries presents an important contribution to dental public health. The results suggest that the chlorhexidine-sodium fluoride mouthrinse potentially possesses a significant effect on inhibition of plaque accumulation and gingivitis. This combination along with the well-established effect of fluoride in the prevention of caries, presents an important contribution to dental public health.

PMID: 17951928 [PubMed - in process]

Characterization of predominant bacteria isolates from clean rooms in a pharmaceutical production unit.

J Zhejiang Univ Sci B. 2007 Sep;8(9):666-72

Authors: Wu GF, Liu XH

AIMS: To screen for the predominant bacteria strains distributed in clean rooms and to analyze their phylogenetic relationships. METHODS AND RESULTS: The bacteria distributed in air, surfaces and personnel in clean rooms were routinely monitored using agar plates. Five isolates frequently isolated from the clean rooms of an aseptic pharmaceutical production workshop were selected based on their colony and cell morphology characteristics. Their physiological and biochemical properties, as well as partial 16S rDNA sequences, were analyzed. Results showed that all the five isolates belong to Gram positive bacteria, of which three were Staphylococcus, one Microbacterium and one Bacillus species. Sensitivity tests for these bacteria isolates to 3 disinfectants showed that isolate F03 was obtuse, and had low susceptivity to UV irradiation, while isolates F02, F01 and F04 were not sensitive to phenol treatment. Isolates F04, F01 and F05 were resistant to chlorhexidine gluconate. CONCLUSION: Bacteria widely distributed in clean rooms are mainly a group of Gram positive strains, showing high resistance to selected disinfectants. SIGNIFICANCE AND IMPACT OF THE STUDY: Clean rooms are essential in aseptic pharmaceutical and food production. Screening bacteria isolates and identifying them is part of good manufacturing practices, and will aid in finding a more effective disinfection method.

PMID: 17726748 [PubMed - indexed for MEDLINE]

The application of in vivo confocal scanning laser microscopy in the management of Acanthamoeba keratitis.

Mol Vis. 2007;13:1319-26

Authors: Matsumoto Y, Dogru M, Sato EA, Katono Y, Uchino Y, Shimmura S, Tsubota K

PURPOSE: To evaluate the role of in vivo laser scanning confocal microscopy (Heidelberg Retina Tomograph II, Rostock Cornea Module, HRTII-RCM) in the management of Acanthamoeba keratitis (AK). METHODS: Four eyes of four patients with AK seen at Keio University Hospital at the Department of Ophthalmology were studied in this single-center, prospective, interventional case series. All patients were routinely examined by slit-lamp microscopy including corneal fluorescein staining. Best corrected visual acuity (BCVA) was also measured before and after the treatment for AK. Both the scraped corneal epithelium and soft contact lens (SCL) storage solution in each patient's SCL case were cultured. Patient corneas were examined regularly using the HRTII-RCM before treatment and after commencement of medications including azoles, echinocandins, and chlorhexidine. RESULTS: All patients had various degrees of conjunctival injection, corneal edema, stromal opacity with radial keratoneuritis with slit-lamp examination. Cultures for AK were positive in three out of four cases by corneal scraping. Contact lens storage solutions were also positive in three of four cases. HRTII-RCM examination could detect Acanthamoeba cysts or trophozoites in all eyes before corneal scraping. No organisms were detectable in any of the cases in any of the corneal layers four to six weeks after treatment. The BCVA improved with treatment in three of four eyes. CONCLUSIONS: HRTII-RCM could effectively demonstrate cysts and trophozoites and the nature of the inflammatory process in AK. In vivo laser scanning confocal microscopy employing HRTII-RCM could provide an end-point for treatment, saving the patient from additional invasive diagnostic procedures and unneeded exposure to long term topical or systemic medications.

PMID: 17679934 [PubMed - indexed for MEDLINE]

Residual antibacterial activity of chlorhexidine digluconate and camphorated p-monochlorophenol in calcium hydroxide-based root canal dressings.

Braz Dent J. 2007;18(1):8-15

Authors: Soares JA, Leonardo MR, Tanomaru Filho M, Silva LA, Ito IY

The purpose of this study was to evaluate the residual antibacterial activity of several calcium hydroxide [Ca(OH)2]-based pastes, placed in root canals of dogs' teeth with induced chronic periapical lesions. Root canals were instrumented with the ProFile rotary system and filled with 4 pastes: G1 (n=16): Ca(OH)2 paste + anesthetic solution; G2 (n=20): Calen paste + camphorated p-monochlorophenol (CMCP); G3 (n=18): Calen; and G4 (n=18): Ca(OH)2 paste + 2% chlorhexidine digluconate. After 21 days, the pastes were removed with size 60 K-files and placed on Petri plates with agar inoculated with Micrococcus luteus ATCC 9341. Pastes that were not placed into root canals served as control. After pre-diffusion, incubation and optimization, the inhibition zones of bacterial growth were measured and analyzed by Mann-Whitney U test at 5% significance level. All pastes showed residual antibacterial activity. The control samples had larger halos (p<0.05). The mean residual antibacterial activity halos in G1, G2, G3 and G4 were 7.6; 10.4; 17.7 and 21.4 mm, respectively. The zones of bacterial growth of G4 were significantly larger than those of G1 and G2 (p<0.05). In conclusion, regardless of the vehicle and antiseptic, all Ca(OH)2-based pastes showed different degrees of measurable residual antibacterial activity. Furthermore, unlike CMCP, chlorhexidine increased significantly the antibacterial activity of Ca(OH)2.

PMID: 17639193 [PubMed - indexed for MEDLINE]

Chlorhexidine's effect on sealing ability of composite restorations following Er:YAG laser cavity preparation.

J Contemp Dent Pract. 2007;8(5):26-33

Authors: Geraldo-Martins VR, Robles FR, Matos AB

AIM: The aim of this study was to evaluate the influence of chlorhexidine on microleakage of composite restorations in class V cavities prepared with a carbide bur (CB) and a erbium:yttrium-aluminum-garnet (Er:YAG) laser. METHODS AND MATERIALS: Cavity preparations were created on the buccal surfaces of 48 bovine incisors using different methods then equally dividing them into four groups. Groups I and II were prepared with a #56 CB in a high speed handpiece while Groups III and IV were prepared with a Er:YAG laser at 350m J/4Hz on enamel and at 80.24 J/cm2 on dentin. The cavity preparations were rinsed with 2% chlorhexidine solution before the application of Clearfill SE Bond system and placement of a Z100 composite resin restoration. After 24 hours, the teeth were polished, thermocycled, and sealed with cosmetic varnish. The samples were then immersed in 2% methylene blue for four hours and sectioned in the buccolingual direction to determine the degree of microleakage. RESULTS: After statistical analysis (Kruskal-Wallis, p<0.05), no significant differences were verified among the tested groups and between the evaluated cervical or incisal margins of the restoration. CONCLUSION: The use of the chlorhexidine did not interfere with the adhesion process regardless of whether a CB or the Er:YAG laser were used to prepare class V cavities when restored with the tested self-etching adhesive system.

PMID: 17618327 [PubMed - indexed for MEDLINE]

[Investigation of the germicidal effect of usnic acid, betadine, savlosol, and desderman on the protoscolexes of lung hydatid cysts]

Turkiye Parazitol Derg. 2007;31(2):101-4

Authors: Esme H, Cift&#xE7;i IH, Solak O, Dilek ON

Injecting scolicidal agents into the intact hydatid cyst and packing the operative field with sponges soaked in scolicidal agents have been used to avoid dissemination of the parasite into the pleural cavity and bronchial system during surgery. The aim of this study was to determine the scolicidal property of different concentrations and exposure times of various agents on the protoscolexes. For this reason, usnic acid, betadine (%10 povidine iodine), savlosol (15% cetrimide-1.5% chlorhexidine), and desderman (96% ethanol and 2-biphenylol) and their various dilutions were used. Protoscolexes were obtained from lungs containing cysts of the naturally infected sheep and viability was determined by dye-uptake (0.1% Eosin). It was found that usnic acid did not completely kill the scolexes in 15 minutes. Betadine, savlosol, and desderman was strongly germicidal in 15 minutes. Savlosol was found to have a germicidal effect at the lowest concentration among the agents studied.

PMID: 17594647 [PubMed - in process]

A prospective randomized trial to reduce oral Candida spp. colonization in patients with hyposalivation.

Braz Oral Res. 2007 Apr-Jun;21(2):182-7

Authors: Torres SR, Peixoto CB, Caldas DM, Akiti T, Barreiros MG, de Uzeda M, Nucci M

Low salivary flow rates are associated with higher oral Candida spp. counts, which may predispose to oral candidiasis. The aim of this study was to compare the effect of stimulating salivary flow rates with that of a regimen of chlorhexidine mouth rinse on the intensity of Candida colonization in patients with reduced salivary flow rates. Thirty-one outpatients were randomized to stimulate salivary output (group 1) or to receive chlorhexidine mouth rinses (group 2). Evaluations were performed at baseline (T0), at end of treatment (T1), and 15 days after last day of treatment (T2). Chewing-stimulated whole saliva samples were collected at each visit. Group 1 showed a constant reduction in median cfu counts, although the difference was significant only between T0 and T2 (p = 0.004). Group 2 showed a reduction in median Candida cfu counts between T0 and T1 (p = 0.01), but the counts increased at T2 (p = 0.01), and the difference between T0 and T2 was not significant (p = 0.8). In conclusion, patients who received salivary stimulation showed reductions of Candida cfu counts in saliva and a trend for increasing salivary flow rates between baseline and end of study evaluations. The use of chlorhexidine mouth rinses dramatically reduced Candida cfu counts, but when patients discontinued treatment, intensity of colonization rose again.

PMID: 17589656 [PubMed - in process]

Bacterial, fungal and yeast contamination in six brands of irreversible hydrocolloid impression materials.

Braz Oral Res. 2007 Apr-Jun;21(2):106-11

Authors: Casemiro LA, Martins CH, de Souza Fde C, Panzeri H, Ito IY

This study assessed the level of contamination of six commercially available irreversible hydrocolloids (two containing chlorhexidine) and identified the contamination present in the materials. Petri dishes containing selective and enriched culture media were inoculated with alginate powder (0.06 g), in triplicate. After incubation (37 degrees C/7 days), the colony-forming units (CFU) were counted and Gram stained. Biochemical identification of the different morphotypes was also performed. The contamination levels for the materials were: Jeltrate--389 CFU/g; Jeltrate Plus--516 CFU/g; Jeltrate Chromatic--135 CFU/g; Hydrogum--1,455 CFU/g; Kromopan--840 CFU/g; and Greengel--59 CFU/g. Gram staining revealed the presence of Gram-positive bacillus and Gram-positive cocci. The bacteria Staphylococcus epidermidis, Bacillus subtilis, Bacillus sp., Bacillus coagulans, Bacillus licheniformis, Bacillus cereus, Micrococcus luteus, and Nocardia sp.; the filamentous fungi Aspergillus niger, Aspergillus flavus, Rhizopus sp., Neurospora sp.; and the yeast Candida sp. were isolated. The contamination detected in the impression materials points out the need for adopting measures to improve the microbiological quality of these materials. The use of contaminated materials in the oral cavity goes against the basic principles for controlling cross-contamination and may represent a risk for debilitated or immunocompromised patients.

PMID: 17589644 [PubMed - in process]

Effect of intracanal medication with calcium hydroxide and 1% chlorhexidine in endodontic retreatment cases with periapical lesions: an in vivo study.

J Formos Med Assoc. 2007 Mar;106(3):217-24

Authors: Ercan E, Dalli M, Du&#xFC;lgergil CT, Yaman F

BACKGROUND/PURPOSE: Calcium hydroxide (Ca(OH)(2)) has been widely used as an intracanal medicament for endodontic retreatment, but very few studies used both Ca(OH)(2) and 1% chlorhexidine (CHX) as intracanal medicaments. The purpose of this study was to assess the in vivo effectiveness of a combination of Ca(OH)(2) and 1% CHX as intracanal medicaments in endodontic retreatment cases with periapical lesions. METHODS: Previous cases of endodontically treated teeth with periapical pathosis in 70 patients (36 men and 34 women, age range 18-60 years) were included. Of these teeth, 59 had received root canal treatment and 11 had been subjected to previous apical surgery, indicating endodontic failure. Following the routine procedures, including canal reshaping and irrigation with 2% CHX, a canal medication material containing Ca(OH)(2) powder and a 1% CHX solution was placed into the root canals. Over a 6-week period, the intracanal medication was periodically changed until the teeth became asymptomatic. Patients were recalled at 3-month intervals for radiographic and clinical examination. RESULTS: Our clinical and radiographic assessment of retreatment cases showed complete healing in 41 (64%) teeth, incomplete healing in 9 (14%) teeth, and failure in 14 (22%) teeth. For complete healing teeth, the healing time varied from 6 to 36 months. The size of the periapical lesions and previous surgical treatment had no influence on the prognosis. CONCLUSION: Our results suggest that a combination of Ca(OH)(2) and 1% CHX can be successfully used as intracanal medicament for disinfection in endodontic retreatment cases with periapical lesions.

PMID: 17389166 [PubMed - indexed for MEDLINE]

In vitro antimicrobial activity of different gutta-percha points and calcium hydroxide pastes.

Braz Oral Res. 2007 Jan-Mar;21(1):35-9

Authors: Tanomaru JM, Pappen FG, Tanomaru Filho M, Spolidorio DM, Ito IY

The aim of this study was to evaluate the antimicrobial activity of different trademarks and compositions of gutta-percha points and calcium hydroxide pastes used in endodontic therapy. The evaluated material consisted of gutta-percha points containing calcium hydroxide (Roeko), gutta-percha points containing chlorhexidine (Roeko), two conventional gutta-percha points (Endo Points and Roeko) and two calcium hydroxide pastes (Calen and Calen/PMCC). Antimicrobial tests included five species of microorganisms: Escherichia coli (ATCC10538), Staphylococcus epidermidis (ATCC12228), Staphylococcus aureus (ATCC6538), Pseudomonas aeruginosa (ATCC27853), and Micrococcus luteus (ATCC9341). The Agar diffusion method was employed. The plates were kept at room temperature for 2 h for prediffusion and then incubated at 37 degrees C for 24 h. The triphenyltetrazolium chloride gel was added for optimization and the zones of inhibition were measured. Statistical evaluation was carried out using analysis of variance and Tukey Test. The obtained results showed that all microbial species used in the study were inhibited by the gutta-percha points containing chlorhexidine and by the calcium hydroxide pastes (Calen and Calen/PMCC), with similar results (p > 0.05). No antimicrobial activity was observed for the other groups. It was concluded that the gutta-percha points containing chlorhexidine presented antimicrobial activity, whereas the gutta-percha points containing calcium hydroxide did not.

PMID: 17384853 [PubMed - in process]

Denture stomatitis.

Skinmed. 2007 Mar-Apr;6(2):92-4

Authors: Chen AY, Zirwas MJ

A 70-year-old woman presented for evaluation of an eruption localized to the area covered by her partial upper denture. Her medical history and physical examination were otherwise unremarkable. She originally had a metal upper partial denture, which she used for many years without difficulty. Four years before presentation, she developed a painful eruption affecting only the tissue covered by the upper partial denture. Contact dermatitis to metal was suspected, and a new upper partial denture constructed primarily of acrylates was fashioned. When she transitioned to the new denture, the inflammation in her oral mucosa persisted and perhaps worsened, despite an excellent fit. Examination revealed striking erythema and mild edema sharply localized to the areas where the partial upper denture contacted the gum ridge. Patch testing was performed and revealed allergies to multiple acrylates, including methyl methacrylate. A swab from the gums was sent for yeast culture. No Candida was detected. Based on suspected candidal overgrowth on the denture, the patient was advised to begin applying nystatin ointment between the gums and the denture, and to start soaking the dentures nightly in chlorhexidine 0.12% solution. In addition, because the relevance of the acrylate allergy was unclear, her dentist was contacted and it was recommended that the dentures be boiled to induce polymerization of any residual un-reacted methacrylate monomers. The patient had a 90% improvement in the clinical appearance and in symptoms at an 8-week follow-up appointment. Due to logistic issues, the dentures had not yet been boiled. The improvement, despite the dentures not having been boiled, was felt to demonstrate that the acrylate allergy was not relevant. The patient has continued to slowly show further improvement over 6 months of follow-up.

PMID: 17366680 [PubMed - indexed for MEDLINE]

Rectal stump lavage: simple procedure resulting in life-threatening complication.

Asian J Surg. 2007 Jan;30(1):72-4

Authors: Liu SY, Lee JF, Ng SS, Li JC, Yiu RY

In colorectal resections, rectal stump lavage is commonly performed prior to primary anastomosis for reducing bacterial counts and minimizing the risk of anastomotic recurrence. Being a potent bactericidal and cytotoxic disinfectant, chlorhexidine is frequently chosen as the irrigation solution of choice for such purposes. Despite its widespread use, the potential for developing chlorhexidine allergy is still a major concern due to the ever-rising number of literature reports of hypersensitivity reactions to chlorhexidine in surgical patients. This report illustrates the first reported case of life-threatening chlorhexidine anaphylaxis after its use in rectal stump lavage for colorectal resection. This report serves as a reminder of the potential danger of this "hidden allergen" in clinical practice.

PMID: 17337376 [PubMed - indexed for MEDLINE]

Susceptibilities of methicillin-resistant Staphylococcus aureus isolates to seven biocides.

Biol Pharm Bull. 2007 Mar;30(3):585-7

Authors: Narui K, Takano M, Noguchi N, Sasatsu M

Minimum bactericidal concentrations (MBCs) of seven biocides for 42 methicillin-resistant Staphylococcus aureus (MRSA) isolates at 5, 30, or 180 min, for hand scrubs or soaks, isolated in 2003 in Japan were determined. The MBC values of glutaraldehyde, povidone iodine, and ethanol were lower than the user concentrations in all exposure times. However, at 5 min exposure of sodium hypochlorite, benzalkonium chloride, alkyldiaminoethylglycine hydrochloride, and chlorhexidine digluconate some strains showed higher MBC values than the user concentrations. These results indicated the possibility that MRSA survived under proper user concentration conditions and exposure time.

PMID: 17329862 [PubMed - indexed for MEDLINE]

Reduction of bloodstream infections associated with catheters in paediatric intensive care unit: stepwise approach.

BMJ. 2007 Feb 17;334(7589):362-5

Authors: Bhutta A, Gilliam C, Honeycutt M, Schexnayder S, Green J, Moss M, Anand KJ

PROBLEM: Bloodstream infections associated with catheters were the most common nosocomial infections in one paediatric intensive care unit in 1994-7, with rates well above the national average. DESIGN: Clinical data were collected prospectively to assess the rates of infection from 1994 onwards. The high rates in 1994-7 led to the stepwise introduction of interventions over a five year period. At quarterly intervals, prospective data continued to be collected during this period and an additional three year follow-up period. SETTING: A 292 bed tertiary care children's hospital. KEY MEASURES FOR IMPROVEMENT: We aimed to reduce our infection rates to below the national mean rates for similar units by 2000 (a 25% reduction). STRATEGIES FOR CHANGE: A stepwise introduction of interventions designed to reduce infection rates, including maximal barrier precautions, transition to antibiotic impregnated central venous catheters, annual handwashing campaigns, and changing the skin disinfectant from povidone-iodine to chlorhexidine. Effects of change Significant decreases in rates of infection occurred over the intervention period. These were sustained over the three year follow-up. Annual rates decreased from 9.7/1000 days with a central venous catheter in 1997 to 3.0/1000 days in 2005, which translates to a relative risk reduction of 75% (95% confidence interval 35% to 126%), an absolute risk reduction of 6% (2% to 10%), and a number needed to treat of 16 (10 to 35). LESSONS LEARNT: A stepwise introduction of interventions leading to a greater than threefold reduction in nosocomial infections can be implemented successfully. This requires a multidisciplinary team, support from hospital leadership, ongoing data collection, shared data interpretation, and introduction of evidence based interventions.

PMID: 17303886 [PubMed - indexed for MEDLINE]

Impact of the direct application of therapeutic agents to the terminal recta of experimentally colonized calves on Escherichia coli O157:H7 shedding.

Appl Environ Microbiol. 2007 Mar;73(5):1493-500

Authors: Naylor SW, Nart P, Sales J, Flockhart A, Gally DL, Low JC

Enterohemorrhagic Escherichia coli O157:H7 is an important intestinal pathogen of humans with a main reservoir of domesticated ruminants, particularly cattle. It is anticipated that the risk of human infection can be reduced by controlling the organism within its reservoir hosts. Several options for the control of E. coli O157:H7 in cattle have been proposed, but none have been demonstrated to be successful in the field. Here we describe a novel experimental method, based on the terminal-rectum-restricted colonization described previously, to eliminate fecal carriage of E. coli O157:H7. In experimentally challenged calves, direct application to the rectal mucosa of either of two therapeutic agents, polymyxin B or chlorhexidine, greatly reduced bacterial shedding levels in the immediate posttreatment period. The most efficacious therapeutic agent, chlorhexidine, was compared in orally and rectally challenged calves. The treatment eliminated high-level shedding and reduced low-level shedding by killing bacteria at the terminal rectum. A rapid-detection system based on the ability to identify E. coli O157:H7 from swabs of the rectal mucosa was also assessed. This test was sufficiently sensitive to identify high-level bacterial carriage. Thus, a combination of the detection method and treatment regimens could be used in the field to eliminate high-level fecal excretion of E. coli O157:H7, so greatly reducing its prevalence within this host and the risk of human infection.

PMID: 17220256 [PubMed - indexed for MEDLINE]

Bone necrosis of the jaws associated with bisphosphonate treatment: a report of twenty-nine cases.

Acta Biomed. 2006 Aug;77(2):109-17

Authors: Merigo E, Manfredi M, Meleti M, Guidotti R, Ripasarti A, Zanzucchi E, D'Aleo P, Corradi D, Corcione L, Sesenna E, Ferrari S, Poli T, Bonaninil M, Vescovi P

Bone necrosis of the jaws is often related to head and neck radiotherapy, to surgical procedures at maxillary or mandibular level but also to various local and systemic factors such as haematological diseases, haemoglobinopathies and systemic lupus eritematosus; its pathogenesis maybe associated with defects of vascularization. Bisphosphonate are synthetic analogues of pyrophosphate used for the treatment of hypercalcemia in patients with malignancies and bone metastasis and for the treatment of many other disorders such as metabolic bone diseases, Paget's disease, and osteoporosis; their pharmacological activity is related to the inhibition of the osteoclastic function which leads to resorption and reduction of bone vascularization. Since the end of 2003 Bisphosphonate-associated Osteonecrosis (BON) has become an increasing problem and the test of that is the increase of the relative published case report and case series. Here we report 29 cases of bone necrosis of the jaws in patients treated with pamidronate (Aredia), zoledronate (Zometa) and alendronate: 15 underwent surgical procedures and 14 occurred spontaneously. Among these patients (21 females, 8 males; mean age between 45 and 83 years); 14 were treated for bone metastasis, 12 for multiple myeloma and 3 for osteoporosis. Bone necrosis involved only maxilla in 7 patients, only mandible in 20 patients and both in 2 patients. Six patients had multiple osteonecrotic lesions, 3 contemporary lesions and 3 non contemporary. In these patients we performed 3 kinds of therapy, associated or not: medical therapy (with antibiotic drugs, antimycotics and antiseptic mouthwashes), surgical therapy with curettage or sequestrectomy and Nd:YAG laser biostimulation.

PMID: 17172192 [PubMed - indexed for MEDLINE]

Molecular characterization of Acanthamoeba isolated from amebic keratitis related to orthokeratology lens overnight wear.

Korean J Parasitol. 2006 Dec;44(4):313-20

Authors: Lee SJ, Jeong HJ, Lee JE, Lee JS, Xuan YH, Kong HH, Chung DI, Ock MS, Yu HS

In an effort to characterize, on the molecular scale, the Acanthamoeba initially isolated from the cornea of an amoebic keratitis patient associated with overnight-wear orthokeratology lens in Korea, we conducted mitochondrial DNA restriction fragment length polymorphism, 18S rDNA sequencing, and drug sensitivity analyses on the isolate (KA/PE1). The patient was treated with polyhexamethylene biguanide, chlorhexidine and oral itraconazole, which resulted in resolution of the patientos ocular inflammation. The majority of the molecular characteristics of the KA/PE1 were determined to be identical, or quite similar, to those of A. castellanii Ma strain, which had been isolated also from amoebic keratitis. The risk of Acanthamoeba keratitis as a potential complication of overnight orthokeratology is briefly discussed.

PMID: 17170573 [PubMed - indexed for MEDLINE]

A meta-analysis of six-month studies of antiplaque and antigingivitis agents.

J Am Dent Assoc. 2006 Dec;137(12):1649-57

Authors: Gunsolley JC

BACKGROUND AND METHODS: The author conducted a systematic review of the literature to evaluate the efficacy of antigingivitis and antiplaque products in six-month trials. He searched electronic databases for six-month randomized clinical studies that evaluated both antiplaque and antigingivitis properties of dentifrices or mouthrinses. In addition, the author solicited unpublished studies from manufacturers. RESULTS: Seventeen studies support the antiplaque, antigingivitis effects of dentifrices containing 0.30 percent triclosan, 2.0 percent Gantrez copolymer. There was no evidence of efficacy for triclosan products containing either soluble pyrophosphate or zinc citrate. Dentifrices with stannous fluoride had statistically significant, but marginally clinically significant, evidence of an antiplaque effect; however, there was both a statistically and clinically significant antigingivitis effect. The largest body of studies (21 studies) supported the efficacy of mouthrinses with essential oils. A smaller body of studies (seven) supported a strong antiplaque, antigingivitis effect of mouthrinses with 0.12 percent chlorhexidine. Results for mouthrinses with cetylpyridinium chloride varied and depended on the product's formula. CONCLUSIONS: The studies in this systematic review provide strong evidence of the antiplaque, antigingivitis effects of multiple agents. These results support the use of these agents as part of a typical oral hygiene regimen.

PMID: 17138709 [PubMed - indexed for MEDLINE]

A scanning electron microscopic evaluation of different root canal irrigation regimens.

Braz Oral Res. 2006 Jul-Sep;20(3):235-40

Authors: M&#xF4;nika CM, Fröner IC

The purpose of this study was to assess the effectiveness of endodontic irrigants in removing the smear layer from instrumented root canal walls using Scanning Electron Microscopy (SEM). The endodontic irrigants used were: 1% sodium hypochlorite (NaOCl); 1% NaOCl mixed to 17% EDTAC; 2% chlorhexidine gel; and Ricinus communis gel. Photomicrographs of the middle and apical thirds were evaluated with the aid of the Fotoscore - v. 2.0 software. The results indicated that the mixture of sodium hypochlorite and EDTAC completely removed the smear layer from dentinal walls. The other endodontic irrigants were not as efficient in cleansing the root canals.

PMID: 17119706 [PubMed - indexed for MEDLINE]

Prevention of nosocomial infection in cardiac surgery by decontamination of the nasopharynx and oropharynx with chlorhexidine gluconate: a randomized controlled trial.

JAMA. 2006 Nov 22;296(20):2460-6

Authors: Segers P, Speekenbrink RG, Ubbink DT, van Ogtrop ML, de Mol BA

CONTEXT: Nosocomial infections are an important cause of morbidity and mortality after cardiac surgery. Decolonization of endogenous potential pathogenic microorganisms is important in the prevention of nosocomial infections. OBJECTIVE: To determine the efficacy of perioperative decontamination of the nasopharynx and oropharynx with 0.12% chlorhexidine gluconate for reduction of nosocomial infection after cardiac surgery. DESIGN, SETTING, AND PARTICIPANTS: A prospective, randomized, double-blind, placebo-controlled clinical trial conducted at the Onze Lieve Vrouwe Gasthuis, Amsterdam, the Netherlands, between August 1, 2003, and September 1, 2005. Of 991 patients older than 18 years undergoing elective cardiothoracic surgery during the study interval, 954 were eligible for analysis. INTERVENTION: Oropharyngeal rinse and nasal ointment containing either chlorhexidine gluconate or placebo. MAIN OUTCOME MEASURES: Incidence of nosocomial infection, in addition to the rate of Staphylococcus aureus nasal carriage and duration of hospital stay. RESULTS: The incidence of nosocomial infection in the chlorhexidine gluconate group and placebo group was 19.8% and 26.2%, respectively (absolute risk reduction [ARR], 6.4%; 95% confidence interval [CI], 1.1%-11.7%; P = .002). In particular, lower respiratory tract infections and deep surgical site infections were less common in the chlorhexidine gluconate group than in the placebo group (ARR, 6.5%; 95% CI, 2.3%-10.7%; P = .002; and 3.2%; 95% CI, 0.9%-5.5%; P = .002, respectively). For the prevention of 1 nosocomial infection, 16 patients needed to be treated with chlorhexidine gluconate. A significant reduction of 57.5% in S aureus nasal carriage was found in the chlorhexidine gluconate group compared with a reduction of 18.1% in the placebo group (P<.001). Total hospital stay for patients treated with chlorhexidine gluconate was 9.5 days compared with 10.3 days in the placebo group (ARR, 0.8 days; 95% CI, 0.24-1.88; P = .04). CONCLUSION: Decontamination of the nasopharynx and oropharynx with chlorhexidine gluconate appears to be an effective method to reduce nosocomial infection after cardiac surgery. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00272675.

PMID: 17119142 [PubMed - indexed for MEDLINE]

Impact of umbilical cord cleansing with 4.0% chlorhexidine on time to cord separation among newborns in southern Nepal: a cluster-randomized, community-based trial.

Pediatrics. 2006 Nov;118(5):1864-71

Authors: Mullany LC, Darmstadt GL, Khatry SK, LeClerq SC, Katz J, Tielsch JM

OBJECTIVE: Within a community-based, cluster-randomized study of the effects of 4.0% chlorhexidine on omphalitis and mortality risk, we aimed to describe the distribution of times to separation and the impact of topical chlorhexidine treatment on cord-separation times. METHODS: Between November 2002 and March 2005, 15123 infants were assigned randomly within communities in southern Nepal to receive 1 of the following 3 cord-care regimens: cleansing with 4.0% chlorhexidine, cleansing with soap and water, or dry cord care. In intervention clusters, field workers cleansed the cord in the home on days 1, 2, 3, 4, 6, 8, and 10 after birth. Newborns were monitored throughout the newborn period for signs of omphalitis, and the time to cord separation was noted. Separation times were compared across treatment groups. Cord infection risk and a range of infant and household characteristics were assessed for their relationships to separation time. RESULTS: The mean separation time was shorter in dry cord care (4.24 days) and soap/water (4.25 days) clusters than in chlorhexidine clusters (5.32 days; mean difference: 1.08 days). Cords of infants who received chlorhexidine were 3.6 times more likely to separate after 7 days. Separation time was not associated with omphalitis. Home-delivered topical antiseptics, facility-based birth, and birth attendant hand-washing were associated with greater likelihoods of cord separation after 7 days of age. CONCLUSIONS: In this setting, the umbilical cord separated more rapidly than observed in hospital-based studies, and the impact of chlorhexidine cleansing on separation times was negligible. Increased cord-separation time attributable to topical chlorhexidine treatment should not be considered a factor in decision-making in settings where the baseline risk of omphalitis is high and chlorhexidine might reduce infection and mortality risks significantly.

PMID: 17079556 [PubMed - indexed for MEDLINE]

The effects of equine skin preparation on transdermal drug penetration in vitro.

Can J Vet Res. 2006 Oct;70(4):317-20

Authors: Mills PC, Cross SE

An increasing number of formulations are applied to equine skin, yet variable penetration can affect efficacy, or the incidence of adverse effects, or both. To investigate the effects of common methods of skin preparation on transdermal drug penetration in vitro, we clipped, harvested, and froze skin samples from 5 Thoroughbred geldings. Thawed samples were prepared as follows: control (no preparation); cleaned with aqueous chlorhexidine (Aq-C, 0.1% w/v); cleaned with alcoholic chlorhexidine (Al-C, 0.5% w/v); shaved (Sh); or tape-stripped (Ta) with the use of adhesive tape. The samples were then placed in diffusion cells, and 2 g of methylsalicylate (MeSa) gel (Dencorub) was applied to the stratum corneum side. The penetration of MeSa and its analyte, salicylate (Sa), through the skin samples was measured over 10 h. Compared with control skin, significantly more MeSa penetrated through skin prepared with Al-C or Sh (P < 0.01) or with Aq-C or Ta (P < 0.05), and significantly more Sa was recovered in the receptor phase from skin prepared with Aq-C, Al-C, or Sh (P < 0.05) or with Ta (P < 0.01). A significantly higher rate of penetration and shorter lag time were also noted for MeSa with all the prepared skin samples, compared with the control samples. The results show that clinical techniques routinely used to clean or prepare skin can significantly affect the rate and extent of penetration of a topically applied drug. This may result in greater systemic availability of active drug, which could lead to enhanced efficacy and, possibly, a higher incidence of adverse effects.

PMID: 17042388 [PubMed - indexed for MEDLINE]

Study of the clinical usefulness of a dental drug system for selective reduction of mutans streptococci using a case series.

J Oral Sci. 2006 Sep;48(3):111-6

Authors: Tamaki Y, Nomura Y, Takeuchi H, Ida H, Arakawa H, Tsurumoto A, Kumagai T, Hanada N

The aim of this study was to evaluate the clinical efficacy and safety of a dental drug delivery system (3DS) for the selective reduction of mutans streptococci. Twenty patients with high levels of mutans streptococci in saliva participated. The efficacy of 0.2% chlorhexidine (CHX) delivered by 3DS in reducing the salivary levels of mutans streptococci compared with total streptococci and lactobacilli was investigated. Each subject was treated by professional mechanical tooth cleaning (PMTC) and subsequently individual trays with CHX for 5 min. Salivary bacterial samples were taken at the baseline and weeks 1-12. A significant reduction in the colony count of mutans streptococci was observed during the first 4 weeks compared with the baseline count, while no significant decrease in the count of total streptococci or lactobacilli was found during 12 weeks. In particular, the proportion of mutans streptococci in total streptococci remained low after 12 weeks. Our results indicate that the new 3DS used in combination with PMTC appears to be a promising intraoral drug delivery system which, when used with a low CHX concentration selectively, effectively reduces mutans streptococci in the oral cavity with no adverse effects.

PMID: 17023742 [PubMed - indexed for MEDLINE]

Multiparameter assessments to determine the effects of sugars and antimicrobials on a polymicrobial oral biofilm.

Appl Environ Microbiol. 2006 Oct;72(10):6734-42

Authors: Yang Y, Sreenivasan PK, Subramanyam R, Cummins D

Clinical studies indicate relationships between dental plaque, a naturally formed biofilm, and oral diseases. The crucial role of nonmicrobial biofilm constituents in maintaining biofilm structure and biofilm-specific attributes, such as resistance to shear and viscoelasticity, is increasingly recognized. Concurrent analyses of the diverse nonmicrobial biofilm components for multiparameter assessments formed the focus of this investigation. Comparable numbers of Actinomyces viscosus, Streptococcus sanguinis, Streptococcus mutans, Neisseria subflava, and Actinobacillus actinomycetemcomitans cells were seeded into multiple wells of 96-well polystyrene plates for biofilm formation. Quantitative fluorescence and confocal laser scanning microscopy (CLSM) examined the influences of dietary sugars, incubation conditions, ingredients in oral hygiene formulations, and antibiotics on biofilm components. Biofilm extracellular polymeric substances (EPS) were examined with an optimized mixture of fluorescent lectins, with biofilm proteins, lipids, and nucleic acids detected with specific fluorescent stains. Anaerobic incubation of biofilms resulted in significantly more biofilm EPS and extractable carbohydrates than those formed under aerobic conditions (P < 0.05). Sucrose significantly enhanced biofilm EPS in comparison to fructose, galactose, glucose, and lactose (P < 0.05). CLSM demonstrated thicker biofilms under sucrose-replete conditions, along with significant increases in biofilm EPS, proteins, lipids, and nucleic acids, than under conditions of sucrose deficiency (P < 0.05). Agents in oral hygiene formulations (chlorhexidine, ethanol, and sodium lauryl sulfate), a mucolytic agent (N-acetyl-L-cysteine), and antibiotics with different modes of action (amoxicillin, doxycycline, erythromycin, metronidazole, and vancomycin) inhibited biofilm components (P < 0.05). Multiparameter analysis indicated a dose-dependent inhibition of biofilm EPS and protein by chlorhexidine and sodium lauryl sulfate, along with distinctive inhibitory patterns for subinhibitory concentrations of antibiotics. Collectively, these results highlight multiparameter assessments as a broad platform for simultaneous assessment of diverse biofilm components.

PMID: 17021225 [PubMed - indexed for MEDLINE]

Comparative in vitro efficacies and antimicrobial durabilities of novel antimicrobial central venous catheters.

Antimicrob Agents Chemother. 2006 Oct;50(10):3283-8

Authors: Hanna H, Bahna P, Reitzel R, Dvorak T, Chaiban G, Hachem R, Raad I

We investigated the efficacies and durability of novel antimicrobial central venous catheters (CVCs) in preventing the adherence of microbial organisms to the surfaces of the CVCs. Novel antimicrobial CVCs investigated in this in vitro study were impregnated with antibiotics (minocycline and rifampin), with Oligon agent (silver, platinum, and carbon black), with approved antiseptics (chlorhexidine and silver sulfadiazine), or with a novel antiseptic agent, gendine, which contains gentian violet and chlorhexidine. When tested against methicillin-resistant Staphylococcus aureus (MRSA) and Pseudomonas aeruginosa, gendine-coated CVC segments provided protection against bacterial adherence significantly more than all other types of tested CVCs (P < 0.05). Gendine-coated CVCs also provided better protection against Candida albicans and Candida parapsilosis than CVCs impregnated with antibiotics or with silver, platinum, and carbon (P < 0.02). After 28 days of being soaked in serum, the CVCs impregnated with chlorhexidine and silver sulfadiazine and the CVCs impregnated with silver, platinum, and carbon had lost antimicrobial activity against MRSA, P. aeruginosa, and C. parapsilosis, and the CVCs impregnated with minocycline and rifampin had lost activity against P. aeruginosa and C. parapsilosis. The CVCs impregnated with gendine maintained antimicrobial activities against MRSA, P. aeruginosa, and C. parapsilosis after 28 days of being soaked in serum. Central venous catheters impregnated with the novel investigational antiseptic gendine showed in vitro efficacy and provided protection against bacterial adherence more than other approved novel antimicrobial-coated CVCs.

PMID: 17005806 [PubMed - indexed for MEDLINE]

Controlled release of chlorhexidine from UDMA-TEGDMA resin.

J Dent Res. 2006 Oct;85(10):950-4

Authors: Anusavice KJ, Zhang NZ, Shen C

Chlorhexidine salts are available in various formulations for dental applications. This study tested the hypothesis that the release of chlorhexidine from a urethane dimethacrylate and triethylene glycol dimethacrylate resin system can be effectively controlled by the chlorhexidine diacetate content and pH. The filler concentrations were 9.1, 23.1, or 33.3 wt%, and the filled resins were exposed to pH 4 and pH 6 acetate buffers. The results showed that Fickian diffusion was the dominant release mechanism. The rates of release were significantly higher in pH 4 buffer, which was attributed to the increase of chlorhexidine diacetate solubility at lower pH. The higher level of filler loading reduced the degree of polymerization, leading to a greater loss of organic components and higher chlorhexidine release rates.

PMID: 16998139 [PubMed - indexed for MEDLINE]

In vitro activity and synergism of amphotericin B, azoles and cationic antimicrobials against the emerging pathogen Trichoderma spp.

J Antimicrob Chemother. 2006 Nov;58(5):1058-61

Authors: Kratzer C, Tobudic S, Schmoll M, Graninger W, Georgopoulos A

OBJECTIVES: The uncommon fungal pathogen Trichoderma shows increasing medical importance particularly in immunocompromised patients. Despite systemic antifungal therapy, prognosis of Trichoderma infection is poor regardless of the type of infection and the therapy used. The aim of the present study was to evaluate the in vitro activity and synergism of double antifungal combinations including amphotericin B, voriconazole, fluconazole, chlorhexidine digluconate and Akacid plus against 15 isolates of Trichoderma longibrachiatum and 1 isolate of Trichoderma harzianum. METHODS: Individual MICs were determined by using broth microdilution method following the NCCLS M38-A guidelines with standard RPMI 1640 broth. Synergy tests were performed using the chequerboard method. RESULTS: All clinical Trichoderma strains showed reduced susceptibility to fluconazole (MICs>or=64 mg/L) and amphotericin B (MICs=2 mg/L), whereas lower MICs of 0.5-1 mg/L were detected for voriconazole. Akacid plus reached the lowest MIC values in a range of 0.06-0.5 mg/L, 4- to 32-fold higher MICs were found for chlorhexidine. No antagonism was observed for any of the antifungal combinations tested. Interaction of amphotericin B and azoles was indifferent (fractional inhibitory concentration index, FICI 2-4). The combination of one azole and one cationic biocide showed different degree of synergism (FICI 0.07-2.03). Interaction of Akacid plus and chlorhexidine resulted in synergism for each Trichoderma isolate (FICI-range 0.05-0.5). CONCLUSIONS: These results demonstrate no interaction between antifungals and some degree of synergism between azoles and cationic antimicrobials against Trichoderma spp.

PMID: 16987867 [PubMed - indexed for MEDLINE]

Morphological analysis of three wound-cleaning processes on potentially contamined wounds in rats.

Acta Cir Bras. 2006 Sep-Oct;21(5):332-40

Authors: d'Acampora AJ, Vieira DS, Silva MT, Farias DC, Tramonte R

PURPOSE: To evaluate the inflammatory response of potentially infected wounds treated with isotonic saline solution, chlorhexidine and PVP-I, seven days after surgery. METHODS: Thirty-two male rats were used, divided into 4 groups. All animals had their surgical wounds infected with a standard bacterial inoculum. Control group (A): animals had their surgical wounds sutured without any kind of cleaning. Saline solution group (B): animals had their wounds cleaned with saline solution. Chlorhexidine group (C): animals had their wounds cleaned with chlorhexidine. PVP-I group (D): animals had their wounds cleaned with PVP-I. Seven days after surgery, all the animals had their skin submitted to microscopic and macroscopic evaluation. RESULTS: Edema was found on all histological slices analyzed, as well as vascular proliferation and congestion. Groups A and D showed presence of mild neutrophilic infiltrate, and moderate lymphocytic and macrophage infiltrate. Group B showed severe neutrophilic, macrophage, and lymphocytic infiltrate. Group C showed moderate neutrophilic, macrophage, and lymphocytic infiltrate. CONCLUSION: Group D was the group which showed inflammatory infiltrate most similar to the group that was not submitted to treatment.

PMID: 16981038 [PubMed - indexed for MEDLINE]

Antimicrobial efficiency of some antiseptic products on endodontic microflora isolated from gangrenous pulp tissue.

J Contemp Dent Pract. 2006 Sep 1;7(4):53-62

Authors: Shurrab MY

AIM: The aims of the study are to investigate the bactericidal effect of three antiseptics (chlorhexidine solution, povidone-iodine solution, and Walkhoff solution) and to determine the minimum inhibitory concentration and their effect on different microbial species. METHODS AND MATERIALS: The study was performed on microflora derived from root canals with simple and complicated pulp gangrene and on pure strains of Enterococcus and Candida albicans. RESULTS: Chlorhexidine and povidone-iodine proved to have antibacterial and antifungal effects if used in the treatment of pulp gangrene and in cases not responding to conventional therapy. CONCLUSION: According to the obtained results, the spectrum of antibacterial agents used in infected canal irrigation can be enlarged to include the agents tested.

PMID: 16957791 [PubMed - indexed for MEDLINE]

Delivery challenges for fluoride, chlorhexidine and xylitol.

BMC Oral Health. 2006;6 Suppl 1:S8

Authors: Featherstone JD

The progression or reversal of dental caries is determined by the balance between pathological and protective factors. It is well established that a) fluoride inhibits demineralization and enhances remineralization, b) chlorhexidine reduces the cariogenic bacterial challenge, and c) xylitol is non-cariogenic and has antibacterial properties. The challenge that we face is how best to deliver these anti-caries entities at true therapeutic levels, over time, to favorably tip the caries balance. High caries risk people, including children with Early Childhood Caries (ECC), are a special challenge, since high cariogenic bacterial activity can override fluoride therapy. Current fluoride and chlorhexidine varnishes deliver all their activity within about 24 hours. Early studies with experimental slow release fluoride devices retained elevated levels of fluoride for months in a therapeutic range but have not been pursued. Preventive dentistry has largely ignored the benefits of reducing the bacterial challenge, partially due to primitive and inadequate delivery systems. For example, Chlorhexidine applied as a rinse partially reduces some bacteria but not others that are hiding within the biofilm. Better antibacterials and better delivery systems are needed. Xylitol delivered by gum or lozenge appears to be effective clinically in reducing cariogenic bacteria and caries levels, but novel systems that deliver therapeutic amounts when needed would be a major advance, especially for young children. Reducing the cariogenic bacterial challenge and enhancing the effect of fluoride by the use of new sustained-delivery systems would have a major effect on dealing with caries as a disease.

PMID: 16934125 [PubMed]

Effectiveness of rotary and hand files in gutta-percha and sealer removal using chloroform or chlorhexidine gel.

Braz Dent J. 2006;17(2):139-43

Authors: Bueno CE, Delboni MG, de Ara&#xFA;jo RA, Carrara HJ, Cunha RS

The purpose of this study was to assess in vitro the efficacy of nickel-titanium K3 rotary files and hand files for removal of gutta-percha and sealer from obturated root canals using either chloroform or chlorhexidine as solvents. Sixty extracted single-rooted bovine teeth with straight, large canals were prepared, obtured and randomly assigned to 3 groups (n=20). The teeth were stored at 37 degrees C for 1 month and then the gutta-percha and sealer were removed using different techniques, as follows. Group I: size 3 Gates-Glidden drills plus size 30 hand K-files and Hedström files and chloroform; Group II: K3 NiTi rotary files and chloroform; and Group III: K3 NiTi rotary files and 2% chlorhexidine gel. Radiographs were taken and scanned and the images were digitized. The total area of the canal and the area with remaining obturation material were measured in millimeters using a computed image analysis system (ImageLab). Data were analyzed statistically by one-way ANOVA and Tukey test at 5% significance level. The groups differed statistically (p<0.05) with respect to the average percentage of remaining gutta-percha and sealer, presenting the following sequence of effectiveness (from most to least effective): Group I (15.48%), Group II (28.42%) and Group III (35.96%). The findings of this study showed that, despite the technique used for removal of filling material, none of the retreated canals were completely free of gutta-percha and sealer remnants. The use of stainless steel hand files resulted in a lesser amount of filling debris than the use of nickel-titanium rotary instruments.

PMID: 16924342 [PubMed - indexed for MEDLINE]

Candida albicans biofilms produce antifungal-tolerant persister cells.

Antimicrob Agents Chemother. 2006 Nov;50(11):3839-46

Authors: LaFleur MD, Kumamoto CA, Lewis K

Fungal pathogens form biofilms that are highly recalcitrant to antimicrobial therapy. The expression of multidrug resistance pumps in young biofilms has been linked to increased resistance to azoles, but this mechanism does not seem to underlie the resistance of mature biofilms that is a model of in vivo infection. The mechanism of drug resistance of mature biofilms remains largely unknown. We report that biofilms formed by the major human pathogen Candida albicans exhibited a strikingly biphasic killing pattern in response to two microbicidal agents, amphotericin B, a polyene antifungal, and chlorhexidine, an antiseptic, indicating that a subpopulation of highly tolerant cells, termed persisters, existed. The extent of killing with a combination of amphotericin B and chlorhexidine was similar to that observed with individually added antimicrobials. Thus, surviving persisters form a multidrug-tolerant subpopulation. Interestingly, surviving C. albicans persisters were detected only in biofilms and not in exponentially growing or stationary-phase planktonic populations. Reinoculation of cells that survived killing of the biofilm by amphotericin B produced a new biofilm with a new subpopulation of persisters. This suggests that C. albicans persisters are not mutants but phenotypic variants of the wild type. Using a stain for dead cells, rare dark cells were visible in a biofilm after amphotericin B treatment, and a bright and a dim population were physically sorted from this biofilm. Only the dim cells produced colonies, showing that this method allows the isolation of yeast persisters. Given that persisters formed only in biofilms, mutants defective in biofilm formation were examined for tolerance of amphotericin B. All of the known mutants affected in biofilm formation were able to produce normal levels of persisters. This finding indicates that attachment rather than formation of a complex biofilm architecture initiates persister formation. Bacteria produce multidrug-tolerant persister cells in both planktonic and biofilm populations, and it appears that yeasts and bacteria have evolved analogous strategies that assign the function of survival to a small part of the population. In bacteria, persisters are dormant cells. It remains to be seen whether attachment initiates dormancy that leads to the formation of fungal persisters. This study suggests that persisters may be largely responsible for the multidrug tolerance of fungal biofilms.

PMID: 16923951 [PubMed - indexed for MEDLINE]

Pilot study to evaluate 3 hygiene protocols on the reduction of bacterial load on the hands of veterinary staff performing routine equine physical examinations.

Can Vet J. 2006 Jul;47(7):671-6

Authors: Traub-Dargatz JL, Weese JS, Rousseau JD, Dunowska M, Morley PS, Dargatz DA

Reduction factors (RFs) for bacterial counts on examiners' hands were compared when performing a standardized equine physical examination, followed by the use of one of 3 hand-hygiene protocols (washing with soap, ethanol gel application, and chlorohexidine-ethanol application). The mean RFs were 1.29 log10 and 1.44 log10 at 2 study sites for the alcohol-gel (62% ethyl alcohol active ingredient) protocols and 1.47 log10 and 1.94 log10 at 2 study sites for the chlorhexidine-alcohol (61% ethyl alcohol plus 1% chlorhexidine active ingredients) protocols, respectively. The RFs were significantly different (P < 0.0001) between the hand-washing group and the other 2 treatment groups (the alcohol-gel and the chlorhexidine-alcohol lotion). The use of alcohol-based gels or chlorhexidine-alcohol hand hygiene protocols must still be proven effective in equine practice settings, but in this study, these protocols were equivalent or superior to hand washing for reduction in bacterial load on the hands of people after they perform routine physical examinations.

PMID: 16898109 [PubMed - indexed for MEDLINE]

Clustering of Enterococcus faecalis infections in a cardiology hospital neonatal intensive care unit.

Braz J Infect Dis. 2006 Apr;10(2):113-6

Authors: Strabelli TM, Cais DP, Zeigler R, Siciliano R, Rodrigues C, Carrara D, Neres S, Lessa S, Uip DE

Early identification of an outbreak is one of the main advantages of routine epidemiological surveillance. Enterococcus spp. used to be regarded as microorganisms of low pathogenicity, because they are part of the normal microbial flora of the gastrointestinal and genitourinary tract. Recently, they have emerged as important pathogenic agents, sometimes causing infections with high mortality rates. We studied a clustering of primary bloodstream infections caused by Enterococcus faecalis in a cardiology hospital neonatal intensive care unit (NICU). Four cases of primary bloodstream infection by E. faecalis were detected from April 15 to May 13, 2004, during active infection surveillance. The isolates were sensitive to glycopeptides. Some aspects of the management of these patients, including the date of insertion and placement of a central venous catheter, prescription of a specific medication, contiguity of beds, personnel attending the patients, and occurrence of diarrhea were analyzed to look for factors that might affect the spread of the microorganisms. Measures taken to hamper the spread included contact precautions throughout the unit, cleansing and disinfection of equipment and surfaces, bathing children with 2% chlorhexidine-gluconate-containing soap, professional reeducation, and reinforcement of all measures to prevent infections. We suggest that there is a need to re-evaluate preventive infection measures and to review the strategies aimed at decreasing the nosocomial infection rate in the NICU.

PMID: 16878262 [PubMed - indexed for MEDLINE]

Effect of rotary instrumentation and of the association of calcium hydroxide and chlorhexidine on the antisepsis of the root canal system in dogs.

Braz Oral Res. 2006 Apr-Jun;20(2):120-6

Authors: Soares JA, Leonardo MR, da Silva LA, Tanomaru Filho M, Ito IY

This study aimed at evaluating the antisepsis of the root canal system (RCS) and periapical region (PR) provided by rotary instrumentation associated with chlorhexidine + calcium hydroxide as intracanal medicament. Chronic periapical lesions were induced in 26 pre-molar roots in two dogs. After microbiological sampling, automatic instrumentation using the Profile system and irrigation with 5.25% sodium hypochlorite solution, with a final rinse of 14.3% EDTA followed by profuse irrigation with physiological saline were carried out in 18 root canals. After drying the canals, a paste based on calcium hydroxide associated with a 2% chlorhexidine digluconate solution was placed inside them. After 21 days, the medication was removed, leaving the root canals empty and coronally sealed. After 96 hours, a final microbiological sample was obtained, followed by histomicrobiological processing by the Brown & Brenn method. Eight untreated root canals represented the control group (C-G). Based on the Mann-Whitney test at a confidence level of 5% (p < 0.05), the procedures of antisepsis used offered significant efficacy (p < 0.05) resulting in 100.0% of the canals free of microorganisms. In the C-G, an elevated incidence of various microbial morphotypes was confirmed in all sites of the RCS, with the presence of microbial colonies in the periapical region. In contrast, the experimental group showed a similar pattern of infection in the RCS, although less intense and a reduced level of periapical infection (p < 0.05). It was concluded that adequate instrumentation followed by the application of calcium hydroxide + chlorhexidine offered significant elimination of microorganisms.

PMID: 16878204 [PubMed - indexed for MEDLINE]

Preventive intervention possibilities in radiotherapy- and chemotherapy-induced oral mucositis: results of meta-analyses.

J Dent Res. 2006 Aug;85(8):690-700

Authors: Stokman MA, Spijkervet FK, Boezen HM, Schouten JP, Roodenburg JL, de Vries EG

The aim of these meta-analyses was to evaluate the effectiveness of interventions for the prevention of oral mucositis in cancer patients treated with head and neck radiotherapy and/or chemotherapy, with a focus on randomized clinical trials. A literature search was performed for reports of randomized controlled clinical studies, published between 1966 and 2004, the aim of which was the prevention of mucositis in cancer patients undergoing head and neck radiation, chemotherapy, or chemoradiation. The control group consisted of a placebo, no intervention, or another intervention group. Mucositis was scored by either the WHO, the National Cancer Institute-Common Toxicity Criteria (NCI-CTC) score, or the absence or presence of ulcerations, or the presence or absence of grades 3 and 4 mucositis. The meta-analyses included 45 studies fulfilling the inclusion criteria, in which 8 different interventions were evaluated: i.e., local application of chlorhexidine; iseganan; PTA (polymyxin E, tobramycine, and amphotericin B); granulocyte macrophage-colony-stimulating factor/granulocyte colony-stimulating factor (GM-CSF/G-CSF); oral cooling; sucralfate and glutamine; and systemic administration of amifostine and GM-CSF/G-CSF. Four interventions showed a significant preventive effect on the development or severity of oral mucositis: PTA with an odds ratio (OR) = 0.61 (95% confidence interval [CI], 0.39-0.96); GM-CSF, OR = 0.53 (CI: 0.33-0.87); oral cooling, OR = 0.3 (CI: 0.16-0.56); and amifostine, OR = 0.37 (CI: 0.15-0.89). To date, no single intervention completely prevents oral mucositis, so combined preventive therapy strategies seem to be required to ensure more successful outcomes.

PMID: 16861284 [PubMed - indexed for MEDLINE]

Results of gastroscope bacterial decontamination by enzymatic detergent compared to chlorhexidine.

World J Gastroenterol. 2006 Jul 14;12(26):4199-202

Authors: Rerknimitr R, Eakthunyasakul S, Nunthapisud P, Kongkam P

AIM: To compare the efficacy of enzymatic detergent with chlorhexidine for gastroscope bacterial decontamination. METHODS: A prospective randomized controlled study was undertaken to evaluate the ability of these 2 agents to achieve high level disinfection in a gastroscope. A total of 260 samples were collected from 5 different gastroscopes. Manual cleaning was done for 10 min with these 2 agents separately (n = 130 each). Then all specimens underwent 2% glutaraldehyde soaking for 20 min. After 70% alcohol was rinsed, sterile normal saline was flushed into each gastroscope channel and 40 mL of sample was collected. The sample was sent for aerobic bacterial culture after membrane was filtered. A colony count greater than 200 cfu/mL was considered significant. RESULTS: The positive culture rate was 4.6% in the enzymatic detergent arm and 3.1% in the chlorhexidine arm. Pseudomonas species were the main organism detected from both groups (60%). Multiple organisms were found from 4 specimens (enzymatic detergent arm = 1, chlorhexidine arm = 3). CONCLUSION: The contamination rate of both types of cleaning solution is equivalent.

PMID: 16830374 [PubMed - indexed for MEDLINE]

Preventing ventilator-associated pneumonia: tiptoeing through a minefield.

Am J Respir Crit Care Med. 2006 Jun 15;173(12):1297-8

Authors: Craven DE, Duncan RA

PMID: 16760355 [PubMed - indexed for MEDLINE]

Value of the chlorhexidine decontamination method for recovery of nontuberculous mycobacteria from sputum samples of patients with cystic fibrosis.

J Clin Microbiol. 2006 Jun;44(6):2237-9

Authors: Ferroni A, Vu-Thien H, Lanotte P, Le Bourgeois M, Sermet-Gaudelus I, Fauroux B, Marchand S, Varaigne F, Berche P, Gaillard JL, Offredo C

The chlorhexidine method was compared to the N-acetyl-l-cysteine-NaOH-oxalic acid decontamination method currently recommended for the recovery of nontuberculous mycobacteria (NTM) from patients with cystic fibrosis. Sputum samples (n = 827) treated with chlorhexidine yielded twice as many NTM-positive cultures as those treated by the reference method (54 [6.50%] versus 27 [3.25%]; P < 0.0001) despite a higher contamination rate (20% versus 14.2%; P = 0.0017).

PMID: 16757627 [PubMed - indexed for MEDLINE]

Use of chlorhexidine-impregnated dressing to prevent vascular and epidural catheter colonization and infection: a meta-analysis.

J Antimicrob Chemother. 2006 Aug;58(2):281-7

Authors: Ho KM, Litton E

OBJECTIVES: Vascular and epidural catheter-related infections cause significant morbidities and mortality in hospitalized patients. This meta-analysis assessed the effect of chlorhexidine-impregnated dressing on the risk of vascular and epidural catheter bacterial colonization and infection. METHODS: Literature search was based on MEDLINE (1966 to 1 November 2005), EMBASE and Cochrane Controlled Trials Register (2005 issue 3) databases. Only randomized controlled clinical trials comparing chlorhexidine-impregnated dressing with placebo or povidine-iodine dressing were included in this meta-analysis. Two reviewers reviewed and extracted the data independently. RESULTS: Eight studies assessing a single type of chlorhexidine-impregnated dressing were identified and subjected to meta-analysis. The chlorhexidine-impregnated dressing reduced the risk of epidural [3.6% versus 35%, odds ratio (OR) 0.07, 95% CI: 0.02-0.31, P=0.0005] and intravascular catheter or exit-site bacterial colonization (14.8% versus 26.9%, OR 0.47, 95% CI: 0.34-0.65, P<0.00001) (overall 14.3% versus 27.2%, OR 0.40, 95% CI: 0.26-0.61; P<0.0001). The use of chlorhexidine-impregnated dressing was associated with a trend towards reduction in catheter-related bloodstream or CNS infections (2.2% versus 3.8%, OR 0.58, 95% CI: 0.29-1.14, P=0.11). Local cutaneous reactions to chlorhexidine-impregnated dressing were reported in 5.6% of the patients in three studies (OR 8.17, 95% CI: 1.19-56.14, P=0.04), and 96% of these reactions occurred in neonatal patients. The number needed to prevent one episode of intravascular catheter-related bloodstream infection was 142 for an average period of catheter in situ of 10 days and a change of dressing every 5 days. The cost of preventing one vascular catheter-related bloodstream infection was estimated to be pound298 (US$532.5). CONCLUSIONS: Chlorhexidine-impregnated dressing is effective in reducing vascular and epidural catheter bacterial colonization and is also associated with a trend towards reduction in catheter-related bloodstream or CNS infections. A large randomized controlled trial is needed to confirm whether chlorhexidine-impregnated dressing is cost-effective in preventing bacterial infection related to vascular and epidural catheters.

PMID: 16757502 [PubMed - indexed for MEDLINE]

Antimicrobial and toxicological profile of the new biocide Akacid plus.

J Antimicrob Chemother. 2006 Jul;58(1):193-7

Authors: Buxbaum A, Kratzer C, Graninger W, Georgopoulos A

OBJECTIVES: Akacid plus is a new member of the polymeric guanidine family of disinfectants. It was especially developed to enhance the antimicrobial activity of this class with significantly less toxicity. The in vitro activity of Akacid plus compared with chlorhexidine digluconate and mupirocin was tested against a total of 369 recent clinical isolates. METHODS: The organisms tested by CLSI reference methods included the following: Staphylococcus aureus (98), Staphylococcus epidermidis (9), Bacillus spp. (2), Enterococcus faecalis (32), Klebsiella spp. (45), Enterobacter spp. (20), Escherichia coli (65), Salmonella spp. (6), Shigella spp. (2), Yersinia enterocolitica (1), Acinetobacter spp. (4), Proteus spp. (7), Pseudomonas aeruginosa (59), Stenotrophomonas maltophilia (4), Candida spp. (10) and Aspergillus spp. (7). In vitro selection of resistance to Akacid plus was carried out on 24 strains. Toxicological analyses were also performed. RESULTS: All tested agents were more effective against Staphylococcus spp. and Bacillus spp. than against E. faecalis and Gram-negative bacteria. The MIC90s of chlorhexidine and mupirocin showed a 4-fold and 32-fold increase for methicillin-resistant S. aureus in comparison with methicillin-susceptible strains, while MIC values of Akacid plus were similar for antibiotic-susceptible and multiresistant strains. Bactericidal action of Akacid plus was observed at 1-2x MIC. The in vitro selection of resistance test showed no increase in MIC values of Akacid plus for any isolate after 30 passages. In addition, Akacid plus showed low oral and dermal toxicity. CONCLUSIONS: These preliminary results demonstrate the broad antimicrobial properties of Akacid plus, which makes it a promising tool for topical application in the prophylaxis and treatment of bacterial and fungal infections.

PMID: 16751199 [PubMed - indexed for MEDLINE]

Vaginal microbicides: detecting toxicities in vivo that paradoxically increase pathogen transmission.

BMC Infect Dis. 2006;6:90

Authors: Cone RA, Hoen T, Wong X, Abusuwwa R, Anderson DJ, Moench TR

BACKGROUND: Microbicides must protect against STD pathogens without causing unacceptable toxic effects. Microbicides based on nonoxynol-9 (N9) and other detergents disrupt sperm, HSV and HIV membranes, and these agents are effective contraceptives. But paradoxically N9 fails to protect women against HIV and other STD pathogens, most likely because it causes toxic effects that increase susceptibility. The mouse HSV-2 vaginal transmission model reported here: (a) Directly tests for toxic effects that increase susceptibility to HSV-2, (b) Determines in vivo whether a microbicide can protect against HSV-2 transmission without causing toxicities that increase susceptibility, and (c) Identifies those toxic effects that best correlate with the increased HSV susceptibility. METHODS: Susceptibility was evaluated in progestin-treated mice by delivering a low-dose viral inoculum (0.1 ID50) at various times after delivering the candidate microbicide to detect whether the candidate increased the fraction of mice infected. Ten agents were tested - five detergents: nonionic (N9), cationic (benzalkonium chloride, BZK), anionic (sodium dodecylsulfate, SDS), the pair of detergents in C31G (C14AO and C16B); one surface active agent (chlorhexidine); two non-detergents (BufferGel, and sulfonated polystyrene, SPS); and HEC placebo gel (hydroxyethylcellulose). Toxic effects were evaluated by histology, uptake of a 'dead cell' dye, colposcopy, enumeration of vaginal macrophages, and measurement of inflammatory cytokines. RESULTS: A single dose of N9 protected against HSV-2 for a few minutes but then rapidly increased susceptibility, which reached maximum at 12 hours. When applied at the minimal concentration needed for brief partial protection, all five detergents caused a subsequent increase in susceptibility at 12 hours of approximately 20-30-fold. Surprisingly, colposcopy failed to detect visible signs of the N9 toxic effect that increased susceptibility at 12 hours. Toxic effects that occurred contemporaneously with increased susceptibility were rapid exfoliation and re-growth of epithelial cell layers, entry of macrophages into the vaginal lumen, and release of one or more inflammatory cytokines (Il-1beta, KC, MIP 1alpha, RANTES). The non-detergent microbicides and HEC placebo caused no significant increase in susceptibility or toxic effects. CONCLUSION: This mouse HSV-2 model provides a sensitive method to detect microbicide-induced toxicities that increase susceptibility to infection. In this model, there was no concentration at which detergents provided protection without significantly increasing susceptibility.

PMID: 16740164 [PubMed - indexed for MEDLINE]

A two-year randomized clinical trial of chlorhexidine varnish on dental caries in Chinese preschool children.

J Dent Res. 2006 Jun;85(6):557-9

Authors: Du MQ, Tai BJ, Jiang H, Lo EC, Fan MW, Bian Z

The objective of this study was to assess the effect of six-monthly professional applications of chlorhexidine varnish on the prevention of dental caries in primary molars in Chinese preschool children. In a double-blinded, randomized, placebo-controlled clinical trial, 334 children aged 4-5 years were randomly divided into two groups. Children in the test group received six-monthly applications of a 40% chlorhexidine varnish, and the control children received a placebo varnish. Caries status of the children was assessed by two calibrated examiners at baseline and after 24 months, according to criteria recommended by the World Health Organization. The two-year mean caries increments in the test and the control group children were 1.0 and 1.6 decayed, missing, or filled molar surfaces (dmfs-molar), respectively, a 37.3% reduction (t test, p = 0.036). No side-effects were found. It was concluded that six-monthly applications of chlorhexidine varnish were effective in reducing the incidence of dental caries in primary molars.

PMID: 16723655 [PubMed - indexed for MEDLINE]

The effects of biocides (antiseptics and disinfectants) on the endospores of Rhinosporidium seeberi.

Indian J Med Microbiol. 2006 Apr;24(2):85-91

Authors: Arseculeratne SN, Atapattu DN, Balasooriya P, Fernando R

No data exists on the activity of biocides (antiseptics and disinfectants) on Rhinosporidium seeberi that causes rhinosporidiosis in humans and animals. On account of the inability to culture R. seeberi, in vitro, dyes were used to assess the morphological integrity and viability of biocide-treated endospores that are considered to be the infective stage of this pathogen. Evan's Blue (EvB) identifies the morphological integrity of the endospores while MTT (3-[4, 5-dimethylthiazol-2yl]-2, 5-diphenyl tetrazolium bromide) identifies metabolic activity through its reduction by cellular dehydrogenases to microscopically visible deposits of insoluble formazan. MTT-negativity has earlier been shown to correlate with absence of growth of yeast and mycelial fungi in culture and could thus indicate the loss of viability of MTT-negative rhinosporidial endospores. Hydrogen peroxide, glutaraldehyde, chloroxylenol, chlorhexidine, cetrimide, thimerosal, 70% ethanol, iodine in 70% ethanol, 10% formalin, povidone-iodine, sodium azide and silver nitrate were tested on freshly-harvested endospores and all biocides caused metabolic inactivation with or without altered structural integrity as shown by absence of MTT-staining after 3, 24 or 36 hour after exposure, while EvB stained only the endospores treated with sodium azide, ethanol, thimerosal, chloroxylenol, glutaraldehyde and hydrogen peroxide. With clinically useful biocides - chlorhexidine, cetrimide-chlorhexidine, 70% ethanol, povidone-iodine and silver nitrate, a total period of exposure of endospores to the biocide, for seven minutes, produced metabolic inactivation of the endospores. Anti-rhinosporidial antiseptics that could be used in surgery on rhinosporidial patients include povidone-iodine in nasal packs for nasal and naso-pharyngeal surgery, chlorhexidine and cetrimide-chlorhexidine on the skin, while povidone-iodine and silver nitrate could have application in ocular rhinosporidiosis.

PMID: 16687856 [PubMed - indexed for MEDLINE]

Comparison of two chlorhexidine rinse protocols on the incidence of alveolar osteitis following the surgical removal of impacted third molars.

J Contemp Dent Pract. 2006 May 1;7(2):79-86

Authors: Metin M, Tek M, Sener I

PRINCIPLES: Alveolar osteitis (dry socket) is the most common complication following the extraction of permanent teeth. This study was undertaken to compare the effect of two chlorhexidine rinse protocols on the incidence of alveolar osteitis in patients undergoing surgical removal of impacted mandibular third molar teeth. METHODS: A prospective randomized clinical trial was conducted among 99 subjects. Patients were randomly assigned into two groups. Subjects were instructed to rinse twice daily with 15 ml of chlorhexidine rinse 30 seconds for one week before and one week after surgery (group I) or one week after surgery (group II). Postoperatively, all patients were instructed to return in one week or sooner if bothersome pain increased or persisted. Data were collected regarding abnormal healing, presence of necrotic tissue, exposed bone, and absence of clot. RESULTS: The results indicated group I and group II were not statistically significant different in the reduction of alveolar osteitis. CONCLUSIONS: To reduce alveolar osteitis after impacted third molar surgery, it was observed use of postoperative chlorhexidine rinse was adequate. The postoperative use of chlorhexidine is more feasible than both preoperative and postoperative use.

PMID: 16685298 [PubMed - indexed for MEDLINE]

More about BON.

J Am Dent Assoc. 2006 Apr;137(4):443-4; author reply 444-5

Authors: Lasser AJ

PMID: 16637471 [PubMed - indexed for MEDLINE]