Health Risk Of Dental Unit Waterline System To Dental Patients ' An Issue Of Concern

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

effect of psidium guajava and piper betle extracts on the morphology of dental plaque bacteria

It has been reported that the aqueous extracts of Psidium guajava and Piper betle leaves showed anti-plaque activities during the early stages of dental plaque formation. The aim of the study was to elucidate if such anti-plaque activities involve any ultra-structural changes to the morphology of three early dental plaque bacteria, Streptococcus sanguinis, Streptococcus mitis and Actinomyces sp. Pure cultures of the bacteria were suspended in BHI medium and treated with the test herbal extracts at the sub-lethal concentrations. The growth mixtures were incubated at 37°C. At the logarithmic growth phase [t1], aliquots of 1 ml of the growth mixtures were fixed and used in the preparation of specimens for SEM studies. Ultra-structural alterations to the morphology of the treated cells noted were compared to those of the cells cultured under untreated conditions. Following exposure of the bacteria to the two test herbal extracts, profound ultra-structural changes to their morphology were observed. The observed structural or morphological alterations could attribute to the bacteria being less active in performing normal physiological metabolic functions and thus rendering them less efficient to multiply. The changes noted included [i] reduced sizes of the bacteria, and [ii] majority cells at the non-dividing state as compared to those cultured under controlled conditions. This study has shown anti-plaque effects of aqueous extract of both P. betle and P. guajava

The Effect of Beverages On The Release of Calcium From The Eanmel Surface

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.