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P Barkvoll

Publications and source records attributed to P Barkvoll.

33 records · Page 2Linked to original sources
PubMed1991

Effect of sodium lauryl sulfate on the uptake of fluoride from NaF and MFP by etched enamel in vitro.

Melsen and Rolla (1983) have previously shown that sodium lauryl sulfate may reduce the cariostatic effect of fluoride when present together with sodium monofluorophosphate during topical application. The aim of the present study was to examine the in vitro deposition of fluoride on etched enamel during topical application with sodium fluoride in combination with sodium lauryl sulfate. In addition, uptake by etched enamel of fluoride sodium monofluorophosphate in combination with sodium lauryl sulfate was examined. It was found that sodium lauryl sulfate decreased the amount of fluoride taken up by the enamel.

Acid Etching, Dental↗
PubMed1989

Effect of nystatin and chlorhexidine digluconate on Candida albicans.

Polyene antibiotics such as nystatin and amphotericin B are among the most widely recommended drugs for use against oral candidiasis. It is also generally accepted that chlorhexidine gluconate is an appropriate adjunct or an alternative to specific antimycotic drugs. The aim of the present study was to examine the effect of the combination of nystatin and chlorhexidine digluconate on Candida albicans in vitro. The minimum inhibitory concentration (MIC) value for the combination of the two drugs was found to be significantly higher than the values for each of the drugs alone, approximately 33 times the MIC value for the nystatin solution and 4 times the value for chlorhexidine digluconate. The results of the MIC study and the presence of a precipitate in all combinations of nystatin and chlorhexidine digluconate showed that the combination of the drugs is not effective in vitro against Candida albicans. The most likely reason is that a low solubility chlorhexidine-nystatin salt is formed, thus rendering the combined drug complex ineffective as an antibiotic agent.

Candida albicans↗
PubMed1989

Interaction between chlorhexidine digluconate and sodium lauryl sulfate in vivo.

Chlorhexidine (CH) is cationic and it forms salts of low solubility with anions such as phosphate, sulfate and carboxyl. Toothpastes contain anionic detergents, one of the most widely used being sodium lauryl sulfate (SLS). The aim of the present study was to examine the possible interaction between CH and the anion SLS in vivo. The interference of SLS on the antiplaque potential of CH was investigated. The study was performed according to a single blind cross over design, and the effect of the interval between prerinsing with an aqueous solution of SLS and the subsequent rinsing with CH was examined. The antiplaque effect was examined by the use of the Silness and Löe plaque-index. The results showed that even a 30-min interval between SLS- and CH-rinsing gave a significantly reduced antiplaque effect of CH, whereas the neutralizing effect of SLS disappeared after 2 h. It can thus be concluded that SLS is not compatible with CH, even when these compounds are introduced separately in the oral cavity. The time between toothbrushing and a CH rinse should at least be 30 min, if a reduction in the antimicrobial effect is to be avoided.

Adult↗
PubMed1989

[Conventional treatment of oral candidiasis--new aspects].

Polyene antibiotics such as nystatin and amphotericin B are among the most widely recommended drugs for use in the treatment of oral candidiasis. It is also generally accepted that chlorhexidine gluconate is an appropriate adjunct or an alternative to specific antimycotic drugs. The aim of the present paper was to discuss the conventional treatment against Candida albicans infections. It has previously been shown in an vitro study that combination of chlorhexidine and nystatin reduced the effect against Candida albicans. The most likely reason is that a low solubility chlorhexidine-nystatin salt is formed, thus rendering the combined drug complex ineffective as an antibiotic agent. Other pharmacologic interactions are also discussed. In the treatment of denture related candidiasis one should keep in mind that some tissue conditioners will inhibit the antifungal activity of amphotericin B. A more restrictive use of combinations of drugs against oral candidiasis is suggested.

Candidiasis, Oral↗
PubMed1989

[Should toothpastes foam? Sodium lauryl sulfate--a toothpaste detergent in focus].

Sodium lauryl sulfate is one of the most widely used synthetic detergents in toothpaste. Generally, surface active agents lower the surface tension, penetrate and loosen surface deposits and emulsify or suspend the debris which the dentifrice removes from the tooth. The concentration in dentifrices usually ranges from 0.5-2.0%. It has previously been shown that sodium lauryl sulfate has the potential to initiate hypersensitivity to metal ions. Furthermore, the mucosal permeability will be increased to oil and water soluble compounds. Experiments from this laboratory indicate that sodium lauryl sulfate will interact with the deposition of fluoride on dental enamel. It is furthermore suggested that this interaction may have the potential to decrease the cariostatic effect of fluorides. Clinical studies from Denmark give support to this statement. In conclusion, sodium lauryl sulfate has some side effects, and future work should therefore be concentrated on finding other possible toothpaste detergents without these side effects.

Dentifrices↗
PubMed1988

Interaction between chlorhexidine digluconate and sodium monofluorophosphate in vitro.

The aim of the present study was to investigate the compatibility of chlorhexidine digluconate and sodium monofluorophosphate since these agents are potential ingredients in future products in preventive dentistry. Varying combinations of chlorhexidine digluconate and sodium monofluorophosphate in water, covering the possible ranges of clinically relevant concentrations of both compounds, were made, incubated for 24 h and observed for precipitation of insoluble salts. The mixtures were analyzed for presence of free chlorhexidine and monofluorophosphate after incubation. The results showed that chlorhexidine digluconate and sodium monofluorophosphate are not compatible in clinically relevant concentrations. A chlorhexidine-monofluorophosphate salt of low solubility in water is presumably formed.

Chemical Phenomena↗
PubMed1988

Effect of sodium lauryl sulfate on the deposition of alkali-soluble fluoride on enamel in vitro.

There are indications that sodium lauryl sulfate may reduce the cariostatic effect of fluoride when present together with sodium monofluorophosphate during topical application. The aim of the present study was to examine the in vitro deposition of alkali soluble fluoride on enamel during topical application with sodium fluoride in combination with sodium lauryl sulfate. It was found that increasing amounts of lauryl sulfate decreased the amount of alkali soluble fluoride deposited on the enamel. The amount of fluoride deposited from toothpaste supernatants was less than that from aqueous solutions of NaF with the same concentration of fluoride. Enamel pieces, pretreated with sodium lauryl sulfate showed a reduced deposition of alkali-soluble fluoride after incubation in a fluoride solution. It was also observed that the presence of lauryl sulfate increased the solubility of CaF2 in water.

Administration, Topical↗
PubMed1988

Effects of inorganic orthophosphate and pyrophosphate on dissolution of calcium fluoride in water.

Calcium and fluoride release from excess solid calcium fluoride was monitored for 15-30 min in aqueous solutions containing various concentrations of inorganic orthophosphate and pyrophosphate. Low concentrations of these ions (1-10 mumol/L) considerably inhibited the rate of dissolution of calcium fluoride. This inhibition was pH-dependent, being reduced at pH values below 5. It is suggested that a reduced calcium fluoride dissolution rate, in the presence of phosphate, can account for the relatively slow loss of calcium fluoride from dental enamel observed in recent clinical studies. It also appears that calcium fluoride coated with phosphate may provide a pH-controlled slow release of fluoride that may be of clinical significance and a major component of the cariostatic mechanism of topically applied fluoride.

Calcium Fluoride↗
PubMed1988

Studies on the interaction between sodium lauryl sulfate and hydroxyapatite using Fourier transformed infrared spectroscopy.

The interaction between sodium lauryl sulfate (SLS) and hydroxyapatite (HA) was studied by using Fourier transformed infrared spectroscopy. The adsorption isotherms to HA and enamel were also established. The results obtained by infrared spectroscopy demonstrated that there was no direct evidence of hydrocarbon interactions between the two compounds since the (CH2)n signal remained unchanged. In contrast reacted mixtures of SLS and HA showed a disappearance of absorption bands between 1220 and 1260 due to stretching of S = 0 bonds. This indicates that the sulfate groups interacted with the HA-crystal surface. Treatment of HA-powder and dental enamel with different concentrations of 35S-labelled SLS showed saturation patterns with a maximum of 3.5 micrograms/mg HA and a maximum of 0.68 microgram/mm2 enamel. This study showed that SLS binds to HA through the sulphate groups and that the binding is most likely electrostatic in nature; the interaction mediated between SLS molecules and calcium ions distributed in the hydration layer of the enamel.

Adsorption↗
PubMed1987

Recurrent herpes labialis in a military brass band.

80-90% of the adult population is known to have neutralizing antibodies to herpes simplex virus type 1 (HSV1), of these 18-32% suffer from occasional recurrent herpes labialis (RHL). It is thought that local trigger factors as external traumata, UV-light and chemical stimuli, or systemic factors like fever or common cold, may induce RHL. The aim of the present study was to investigate the frequency of RHL in a military brass band and compare this with the frequency of the disease in a control population of soldiers from the same unit. Both populations were national servicemen aged 19-22 yr. The diagnosis of RHL was based on the presence of herpetic vesicles in the labial region. Of the diagnosed cases, 10% were confirmed by laboratory procedures according to standard methods. The incidence of RHL over a period of 8 months was twice as frequent in the group of brass and woodwind players as in the control group of soldiers from the same military unit. This may indicate that the mechanical trauma to the labial tissue which occurs during playing may cause the increased frequency of RHL in musicians.

Adult↗
PubMedDate not supplied

Antiplaque, antibacterial, and anti-inflammatory properties of triclosan mouthrinses in combination with zinc citrate or polyvinylmethylether maleic acid (PVM-MA) copolymer.

The antibacterial agent triclosan has demonstrated antiplaque and antigingivitis activity in several clinical studies. Retention of antiplaque agents is of significance for their clinical effect. Triclosan has a relatively rapid clearance from the oral cavity, and attempts have been made to increase its oral retention. In the present clinical antiplaque study, it was found that 0.5% copolymer polyvinyl-methylether maleic acid (PVM-MA) or 0.5% zinc citrate, which are both added to commercial products, inhibited plaque formation to a similar degree when used in combination with 0.3% triclosan, 1.5% sodium lauryl sulfate (SL.S) and diluted propylene glycol (PG) in water (1:8). Plaque inhibition was significantly improved compared to a placebo solution. It was shown that these results could not be explained by an increase in antibacterial activity or by a change in the critical micellar concentration. The effect of the same solutions on SLS-induced inflammation on skin was also tested. It was seen that the triclosan/ zinc citrate solution and the control (triclosan/ethanol) decreased the inflammatory response, whereas the solutions containing triclosan in either propylene glycol (PG) or copolymer/PG did not exhibit any anti-inflammatory capacity.

Adult↗