How can its presence be detected?

     There are methods for determining how well you are taking care of your teeth. Two of these methods are very useful. If you would like to assess your plaque status in a quick and easy manner, we recommend disclosing tablets. If you want to test your susceptibility to developing dental caries, the Snyder Test is the way to go. This method will require more time and access to lab equipment. Follow the sets of instructions below to assess your oral status today.

Disclosing Tablets (for the non-scientist)

Disclosing tablets contain a harmless red dye which is attracted to the plaque on your teeth.  The material that is dyed upon chewing is referred to as the pellicle, a glycoprotein deposit derived from salivary components that adhere to the tooth surface. It is the formation of the pellicle that constitutes the first step in plaque formation. This method has been used by dentists for years to help patients see their problem areas in toothbrushing. Plaque areas will turn red upon chewing the tablet. The special two-toned feature found in some tablets  colors old plaque blue and new plaque red, allowing one to see where they failed to brush thoroughly.

                                                    1) Chew a disclosing tablet for 60 seconds, swishing the saliva in your mouth
                                                     2) Spit and raise
                                                     3) Brush your teeth, removing the dye
                                                     4) Chew another tablet and repeat first and seconds steps
                                                     5) Observe blue and red areas and consider these areas when trying to improve your technique in the future

The Snyder Test (for the scientist)

     The Snyder Test is used to test the rate of acid production in the mouth, which indicates your susceptibility to dental caries. The test bases this conclusion on the assumption that Lactobacillus is responsible for the formation of caries. Bromo cresol green is the indicator and the pH is adjusted to 4.8, which is unsuitable for most bacteria other than Lactobacillus. As growth occurs in the tubes, the pH lowers and the broth exhibits a color change to yellow. The faster the change in color, the more concentrated the presence of Lactobacillus in your saliva.

The following ingrediants were added to an Erlenmeyer flask of de-ionized water, bringing the volume to 0.5 L.
        *10.0 g Agar
        *10.0 g Lactose
        *10.0 g Tryptose
        *2.5 g NaCl
        *10.2 ml Bromocresol green

 The solution is gently heated to a boil and then autoclaved for 15 minutes at 13 psi pressure-118 C. The agar is then distributed into 10.0ml sterile test tubes and the agar is then cooled to a temperature of 50 - 48 C using a thermometer. The agar is then inoculated with a sputum sample is added to the agar and covered with a sterile stopper. The medium is then incubated at 37 C at an initial pH of 4.8 + or ­ 0.2 for 72 hours.

A change in color represents a change in pH below 4.8 and the presence of Lactobacilli

Snyder Test color changeSnyder test extreme change

                                                                         Early color change to light green    Extreme color change after 24 hours

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