6th Grade · Science · Activity · shared by Luke Morgan
Discover the chemistry of the oral microbiome, pH, and bacteria's role in dental health with this free 6th Grade Science activity.
The pH Battle: Sugar and Your Oral Microbiome
Every time you eat or drink, you are not just feeding yourself; you are also feeding a massive community of microscopic organisms living in your mouth. This community is called your oral microbiome . Scientists use the pH scale to measure how acidic or basic an environment is. A neutral pH is 7.0. If the pH drops below 7.0, the environment becomes acidic. If the pH rises above 7.0, it becomes basic (alkaline).
In a healthy mouth, the pH stays near neutral, which keeps your tooth enamel strong. However, certain bacteria, specifically Streptococcus mutans , can change this balance. When these bacteria consume sugar, they go through a process of fermentation that releases acid as a byproduct. This acid lowers the pH of your mouth, creating an environment that can dissolve the minerals in your teeth.
Researchers recently conducted a controlled scientific investigation to observe how the oral microbiome reacts to different snack varieties. They monitored the plaque pH levels of twenty middle school participants over a duration of forty minutes. At the initiation of the experiment, every student maintained a neutral oral environment of approximately 7.1. One group of students consumed a sugary snack consisting of chocolate and soda. The second group consumed a snack of plain celery and water. The researchers recorded the pH measurements at five-minute intervals to document the fluctuations. Their objective was to determine how rapidly the bacterial community generated acid after being exposed to concentrations of glucose and sucrose. The data collected provides a significant look at the relationship between dietary selections and the chemical equilibrium inside the human mouth.
Experimental Data: Plaque pH Levels After Snacking