RESUMEN
Water delivered through dental unit waterline system(DUWS) is often reported contaminated with microbesdislodged from biofilm that forms within the tubingof a dental chair unit (DCU). ADM: The study aimedat evaluating the sanitary level of DCU water froma teaching dental clinic. Materials: The presence ofpathogenic bacteria which include total coliforms, faecalcoliforms, E. coli, faecal streptococci and P. aeruginosawere determined using conventional microbiologicalmethods while PCR technique was used to identify othermicrobial contaminants. Result: pH of DCU water wasfound slightly acidic at pH 5.4-5.5 and the temperaturewas 23°C. Pathogenic contaminants were absent butthe DCU water was highly loaded with Sphingomonasrhizogenes (17.9%), Sphingomonas dokdonesis(79.5%), Sphingomonas mucosissima (1.1%) andMethylobacterium radiotolerans (1.5%). The high load ofmicrobes that exceeded 200 cfu/ml was of great concernas it failed to meet recommendation set by the AmericanDental Association
RESUMEN
In this study, the effect of beverages (Coke TM, Sprite™, Ribena™, Chrysanthemum tea and mineral water) on the demineralisation of the enamel surface was investigated. Demineralisation was determined by the rate of calcium released from the enamel surface on exposure to the beverages. Calcium was determined using the EDTA titration method. The pH of these beverages was measured using a pH meter and found to be in the acidic range (2.43 to 5.79) while mineral water which served as a control has a pH of 7.00. Ii was found that the rate of calcium released from Coke™(0.76 J..lg/min) showed a significant mean difference from Sprite™ (0.38 J..lg/min), Chrysanthemum tea (0.10 J..lg/min) and mineral water (0.00 J..lg/min)at p< .05, but was however not significantly different from Ribena™. Likewise, Chrysanthemum tea and mineral water also showed statistically no significant mean difference in the released of calcium during the study period. The results obtained in this study indicated that beverages with low pH may pose detrimental effect on the enamel surface which could have clinical implication, especially in people with salivary gland dysfunction or low salivary flow.
