salicylates and butyl-phthalyl-butyl-glycolate

Variation in the components of soft lining materials, i.e. the size of polymer particles, the ethyl alcohol content of the liquids and the type of plasticizer, were investigated with respect to their effects on the growth and colonization of Candida albicans. Inhibitory effects on fungal growth and/or acid production were found to vary depending upon the components of soft lining materials. In particular, two plasticizers, benzyl benzoate (BB) and benzyl salicylate (BS), significantly decreased the growth rate, whereas the size of polymer particle had little effect on fungal growth. Ethyl alcohol content of liquid significantly affected the fungal growth and/or acid production depending upon the plasticizer used. For instance, in the case of BS, the antifungal effect was related to ethyl alcohol contents, whereas a reverse effect was observed with benzyl n-butyl phthalate (BBP). Further examination using scanning electron microscopy revealed that Candida blastospores colonized lining materials in the following two ways depending on the plasticizers used. On the BS and dibutyl phthalate (DBP) specimen, the blastospore of this yeast associated loosely, whereas, in the case of BB, BBP and butyl phthalyl butyl glycorate (BPBG), fungal blastospore tightly and invasively colonized onto the specimens. These results clearly demonstrated a relationship between components of soft lining materials and fungal growth and colonization.

Topics: Analysis of Variance; Antifungal Agents; Benzoates; Biofilms; Candida albicans; Denture Liners; Dibutyl Phthalate; Ethanol; Hydrogen-Ion Concentration; Methacrylates; Phthalic Acids; Plasticizers; Salicylates; Spores, Fungal; Statistics, Nonparametric; Wettability

An evaluation has been made of the soft polymer gel systems of the type used as prosthodontic short-term denture-lining materials. The purpose of the study was to determine the effect upon gel strength and gelation time produced by variations in the composition of the plasticizer liquids. Poly(ethylmethacrylate) co-polymers were mixed with combinations of ethyl alcohol and the esters dibutyl phthalate (DBP), butylphthalyl butylglycolate (BPBG), and benzyl salicylate (BS). The relative rate of gelation of plasticizer polymer compositions was obtained by means of a reciprocating rheometer. The gelation rate was found to increase rapidly with an increase in the ethyl alcohol content. Significantly shorter gelation times were also found with liquids containing the lower-molecular-weight esters. A linear relationship was found between the ethyl alcohol content and the log of the gelation time. The higher-molecular-weight esters produced the strongest gel. A linear relationship was found between the gelation (log) times and the seven-day puncture strength. The ratio of polymer to plasticizer liquid was found to have a very significant influence upon the puncture strength and gelation time. Molecular weight or molecular volume of the ester plasticizers was found to have a greater influence on gel formation than the cohesive energy parameter. The strong polar bonding of ethyl alcohol was found to have a significant influence on both the rate of gel formation and the subsequent gel strength. The data indicate that controlled variations in the characteristics of plasticity and gel strength of dental soft polymer systems can be made to suit different clinical prosthodontic requirements.

Topics: Chemical Phenomena; Chemistry, Physical; Dibutyl Phthalate; Ethanol; Gels; Hydrogen Bonding; Methylmethacrylates; Plasticizers; Polymers; Rheology; Salicylates; Stress, Mechanical; Time Factors