1. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Mouthwash Dental Plaque: A Microbial Biofilm

2. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Introduction Oral Biofilms and Plaque The BIG Picture Mouthwash’s Fave Five 2 Q: What is a Biofilm? A: Well organized community of microorganisms protected by a matrix, usually formed under fluid conditions. Oral Biofilms and Plaque

3. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Introduction Oral Biofilms and Plaque The BIG Picture Mouthwash’s Fave Five 3 Plaque is a form of biofilm Dental plaque consists of many bacterial species, but the most dominant are S. sanguis, and S. mutans. Q: How is plaque formed? A: By the WEAK attachment of these bacterial species to salivary glycoproteins that form on the surface of your teeth. Oral Biofilms and Plaque

4. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Introduction Oral Biofilms and Plaque The BIG Picture Mouthwash’s Fave Five 4 An enzyme on the surface of S. mutans called glycosyl transferase, uses dietary sugars (mainly sucrose), and forms extracellular sticky polymers of glucose (AKA, plaque). Oral Biofilms and Plaque

5. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Introduction Oral Biofilms and Plaque The BIG Picture Mouthwash’s Fave Five 5 Basic Properties of Biofilms are: Consists of many microcolonies These microcolonies have different environments, and they send out nutrients, waste, and oxygen to each other through fluid channels They love low pH environments Most microorganisms in biofilms are resistant to antibiotics. Not good! Oral Biofilms and Plaque

6. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Introduction Oral Biofilms and Plaque The BIG Picture Mouthwash’s Fave Five 6 Oral Biofilms and Plaque

7. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia The BIG Picture Introduction The BIG Picture Mouthwash’s Fave Five 7 Lets try to target what it loves! Can we create a neutral environment? Or better, use inhibitors of acid production? EX: Flouride, which increases resistance to enamel demineralization and promotes remineralization. How do we control plaque?

8. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Mouthwash’s “Fave Five” Introduction The BIG Picture Mouthwash’s Fave Five 8 1.A device that can produce fluorides. 2.A device that maintains the pH of a healthy mouth, base production. 3.Vary the oxygen concentration, redox agents such as methylene blue inhibits the growth of gingivitis forming bacteria. 4.Produce the wintergreen scent, or even better, different smelling scents. 5.The test dummy. Just kidding! Five projects for our Fave Five:

9. 5/8/08Caltech iGEM Meeting #3 Presentation by Robert Ovadia Sources Introduction The BIG Picture Mouthwash’s Fave Five 9 1.Overman, Pamela R. Biofilm. Journal of Contemporary Dental Practice Volume 1, No. 3, Sumer Issue 2000. 2.Marsh, Philip D. Dental plaque as a biofilm and microbial community - implications for health and disease. BMC Oral health. 10 July 2006. 3.Marsh, Philip D. Dental Plaque as a Microbial Biofilm. Caries Research 2004;38:204-211 4.Enamel picture from Wikipedia.