Whole Saliva has a Dual Role on the Adherence of Candida albicans to Polymethylmetacrylate.

Adhesion of Candida albicans to acrylic of dental prostheses or to salivary macromolecules adsorbed on their surface is believed to be a critical event in the development of denture stomatitis. In previous studies our group has shown that adhesion of C. albicans germ tubes to polystyrene is decreased by saliva whereas C. albicans yeast cells adhesion to the same material is enhanced. The results presented in this study confirm this dual role played by whole saliva, since it decreased the adhesion of germ tubes but increased the adhesion of yeast cells to polymethylmetacrylate (PMMA). These effects mediated by whole saliva do not seem to be related to an inhibition of the germination of C. albicans, since similar levels of filamentation were observed in presence and absence of saliva. These results may give new insights into the conflicting role of saliva in the adhesion of C. albicans to acrylic resins of dental prostheses.

Efecto de polímeros sobre los niveles de IgAs anti Streptococcus mutans y la producción de dextranos de Streptococcus mutans autóctonos (estudio in vitro e in vivo) / Effect of polymers on the levels of lgAs anti Streptococcus mutans and the production of dextran of autothonous Streptococcus mutans(study in and in vivo)

Se evaluó el efecto de Quitosan de Alto Peso Molecular (QAPM) (0.25-0.50 g% P/V; NaOH 1M) y Alginato de Sodio (AI-Na) 0.10-0.50 g% P/V; CaCl2 1 M, sobre los niveles de IgAs anti Streptococcus mutans y la producción de dextranos. Se estudió en saliva (in vitro) el efecto de los polímeros a 5', 8h y 24 h y en saliva extraída de diez sujetos sanos, (in vivo) a 0, 1 y 3 h posteriores a la realización de un buche con polímero. Los niveles de IgAs anti St mutans determinados por ELlSA, no revelaron diferencias estadísticamente significativas con respecto al control (p=0.05). Se determinó la producción de dextranos en presencia de diferentes concentraciones de polímeros mediante espectrofotometría (λ=520), utilizando de 1 a 5.108 UFC/ml de St. mutans en caldo sacarosa 8,5%. Los resultados mostraron reducción significativa, en la formación de dextranos respecto al control (p<0.05), siendo de 32% para QAPM 0.25 g% P/V y 66,8% para QAPM 0.50 g% P/V,en tanto que para AI-Na 0.10 g% P/V fue del 30% y AI-Na 0.50 g% P/V fue del 32%. Se concluye que QAPM y AI-Na , en razón de sus características físico-químicas que les permiten formar uniones tipo puente hidrógeno, y cadenas poliméricas que les confieren elasticidad suficiente para acceder a las distintas estructuras de la cavidad oral brindan expectativas para la investigación de nuevas formulaciones terapéuticas de aplicación odontológica (AU)

Effect of High Molecular Weight Quitosan (HMWQ) (0.25-0.50 g% P/V, NaOH 1M) and Sodium Alginate (Na-Al) (0.10-0.50 g% P/ V. CaCI2 1 M, was evaluated on the levels of IgAs anti Streptococcus mutans and the production of dextran. It was studied in saliva (in vitro) the effect of the polymers to 5', 8h and 24 h and in saliva from ten healthy subjects (study in vivo,) to 0, 1 and 3 h after the execution of a mouth rinse with polymers. The levels of IgAs anti St mutans were determined by ELlSA, they did not reveal statistically significant differences with regard to the control (p=0.05). The dextran production was determined at different concentrations of polymers by means of espectrofotometria (λ=520), using a suspension from 1 to 5.108 UFC ml of St mutans in sucrose broth 8,5%. The results showed significant reduction, to the formation of dextran with respect to the control (p<0.05), being for 32% to HMWQ 0.25 g% PN and 66,8% for HMWQ 0.50 g% P/V, while for Na-Al 0.10 g% PN was 30% and Na-Al 0.50 g% P V was the 32%. It is concluded that QAPM and Al- Na, with regard to their characteristic physical and chemistry that permit to form hydrogen bond Iike, and polymeric chains that confer sufficient elasticity to agree to the different structures of the oral cavity, offer expectations for the therapeutic investigation of new formulations of deontological application (AU)

Low and high molecular weight chitosans interactions with Streptococcus mutans: an in vitro study.

We evaluated the in vitro capacity of high and low molecular weight chitosans (HMWCh and LMWCh) to inhibit the adherence of strains of S. mutans obtained from the American Type Culture Collection (ATCC,25175) to artificial saliva-coated hydroxiapatite beads. The effect of these biopolymers was assessed in terms of pH, ionic force, minimum inhibitory concentration (MIC) and antibacterial activity. The results show that HMWCh is modified by a rise in pH (7.0) and ionic strength. The induced conformational changes lead to the formation of rigid meshes capable of aggregating and entrapping S. mutans. This process is associated to the properties of HMWCh. LMWCh gave rise to smaller aggregates that exhibited a comparatively reduced interaction capacity. The MIC for HMWCh was 0.5 g% and evidenced the bacteriostatic action of the aggregates. We conclude that HMWCh would exert an inhibitory effect on the process of specific adsorption of S. mutans to saliva-coated hydroxiapatite beads.

Low and high molecular weight chitosans interactions with Streptococcus mutans: an in vitro study

We evaluated the in vitro capacity of high and low molecular weight chitosans (HMWCh and LMWCh) to inhibit the adherence of strains of S. mutans obtained from the American Type Culture Collection (ATCC,25175) to artificial saliva-coated hydroxiapatite beads. The effect of these biopolymers was assessed in terms of pH, ionic force, minimum inhibitory concentration (MIC) and antibacterial activity. The results show that HMWCh is modified by a rise in pH (7.0) and ionic strength. The induced conformational changes lead to the formation of rigid meshes capable of aggregating and entrapping S. mutans. This process is associated to the properties of HMWCh. LMWCh gave rise to smaller aggregates that exhibited a comparatively reduced interaction capacity. The MIC for HMWCh was 0.5 g

and evidenced the bacteriostatic action of the aggregates. We conclude that HMWCh would exert an inhibitory effect on the process of specific adsorption of S. mutans to saliva-coated hydroxiapatite beads.

Low and high molecular weight chitosans interactions with Streptococcus mutans: an in vitro study.

We evaluated the in vitro capacity of high and low molecular weight chitosans (HMWCh and LMWCh) to inhibit the adherence of strains of S. mutans obtained from the American Type Culture Collection (ATCC,25175) to artificial saliva-coated hydroxiapatite beads. The effect of these biopolymers was assessed in terms of pH, ionic force, minimum inhibitory concentration (MIC) and antibacterial activity. The results show that HMWCh is modified by a rise in pH (7.0) and ionic strength. The induced conformational changes lead to the formation of rigid meshes capable of aggregating and entrapping S. mutans. This process is associated to the properties of HMWCh. LMWCh gave rise to smaller aggregates that exhibited a comparatively reduced interaction capacity. The MIC for HMWCh was 0.5 g

and evidenced the bacteriostatic action of the aggregates. We conclude that HMWCh would exert an inhibitory effect on the process of specific adsorption of S. mutans to saliva-coated hydroxiapatite beads.

A comparative study in vivo of the therapeutic effect of triclosan, hexetidine and chitosan.

The present clinical study was performed to comparatively assess the therapeutic effect of Low and High Molecular Weight Chitosan (LMWCh and HMWCh), hexetidine, triclosan. Plaque index, saliva buffering capacity and bacteriological controls for S. mutans and lactobacilli, were performed. The plaque and bacterial indices revealed statistically significant differences between groups. Buffering capacity was similar using, hexetidine, and triclosan, whereas it was maximum in 100% of the patients in the LMWCh and HMWCh groups. Only 0.5% HMWCh induced low activity of S. mutans in 100% of the patients and caused complete inhibition of lactobacilli growth. No changes were observed in the profile of salivary proteins. The present clinical study confirms the therapeutic efficacy of the chitosan as a bacteriostatic agent.

A comparative study in vivo of the therapeutic effect of triclosan, hexetidine and chitosan

The present clinical study was performed to comparatively assess the therapeutic effect of Low and High Molecular Weight Chitosan (LMWCh and HMWCh), hexetidine, triclosan. Plaque index, saliva buffering capacity and bacteriological controls for S. mutans and lactobacilli, were performed. The plaque and bacterial indices revealed statistically significant differences between groups. Buffering capacity was similar using, hexetidine, and triclosan, whereas it was maximum in 100

of the patients in the LMWCh and HMWCh groups. Only 0.5

HMWCh induced low activity of S. mutans in 100

of the patients and caused complete inhibition of lactobacilli growth. No changes were observed in the profile of salivary proteins. The present clinical study confirms the therapeutic efficacy of the chitosan as a bacteriostatic agent.

A comparative study in vivo of the therapeutic effect of triclosan, hexetidine and chitosan.

The present clinical study was performed to comparatively assess the therapeutic effect of Low and High Molecular Weight Chitosan (LMWCh and HMWCh), hexetidine, triclosan. Plaque index, saliva buffering capacity and bacteriological controls for S. mutans and lactobacilli, were performed. The plaque and bacterial indices revealed statistically significant differences between groups. Buffering capacity was similar using, hexetidine, and triclosan, whereas it was maximum in 100

of the patients in the LMWCh and HMWCh groups. Only 0.5

HMWCh induced low activity of S. mutans in 100

of the patients and caused complete inhibition of lactobacilli growth. No changes were observed in the profile of salivary proteins. The present clinical study confirms the therapeutic efficacy of the chitosan as a bacteriostatic agent.