Abstract:The development of oral biofilm consisting of early settlers and late settlers in the presence and absence of sucrose using a simulated mouth model was investigated. The experiments were carried out by growing the early settlers' biofilm consisting of Strep. mitis and Strep. sanguinis and late settlers' biofilm of Strep. mutans in the simulated mouth system. Experiments using three different nutrient conditions (A, B and C) were carried out. In A, sterile saliva was used as the nutrient source in which the early settlers were suspended and pumped into the simulated mouth system and allowed to grow for 24 hrs. In B, 1% of BHI broth was added to the sterile saliva three times a day at 6 hrs interval to demonstrate the effect of glucose on the development of the biofilms. In C, the 1% BHI was supplemented with 1% sucrose in order to show the effect of glucose in the presence of sucrose on the development of the biofilm. The experiments were subsequently repeated with the late settlers. In all the experiments, A serves as the control where the nutrient source is minimal. The data collected were analyzed using Student t-test. From the results obtained, it was observed that both glucose and sucrose enhanced the development of early and late settlers' biofilms. The growth of late settlers' biofilm however, was found to be significantly higher in the presence of sucrose (93x10 6 CFU mL¯1) compared to glucose (66x10 6 CFU mL¯1) with a p value <0.05.

Saliva collection is non-invasive and less stressful when compared with blood collection. Extensive studies on saliva has been carried out and the use of saliva as a biological sample in clinical diagnosis and for monitoring hormones, drugs and pollutants and viruses has been recommended. The complexities associated with saliva such as proper collection device and strict standardisation of a number of factors which include time of collection, types of saliva and storage made it less favourable to blood.