6th Grade · Science · Reading Passage · shared by Luke Morgan
Explore the science of dental health, including mouth bacteria, plaque, and cavities, with this free 6th Grade Science reading passage.
Inside your mouth, a tiny world exists where millions of microscopic creatures live and work together every single day. This busy environment is filled with different types of bacteria that grow on the surfaces of your white teeth. When these bacteria stick together, they form a sticky, clear layer of film that scientists call plaque . While some of these tiny organisms are helpful, others can cause problems if they grow too large in number. Understanding how these different groups interact helps us keep our smiles healthy and our breath smelling fresh and clean.
One of the most famous residents of this sticky film is a bacterium known as Streptococcus mutans. This specific type of bacteria loves to eat the sugars that are left behind after you enjoy a sweet snack. As it eats, it produces a strong acid that slowly wears away the hard outer layer of your teeth. Over time, this constant acid attack creates small holes that we recognize as painful cavities or permanent tooth decay. Because it thrives in sugary environments, this bacterium is often considered the main villain in the story of dental health.
Fortunately, another resident named Streptococcus salivarius acts as a friendly neighbor that helps protect your mouth from damage. This bacterium is naturally found in high numbers on the tongue and the soft tissues inside your cheeks. Unlike its harmful cousin, this helpful organism does not produce the dangerous acids that lead to holes. Instead, it works to maintain a healthy balance by taking up space and resources that the bad bacteria need.
These two types of bacteria are constantly locked in a silent competition for survival within the crowded space of your mouth. They both need a place to live and a steady supply of nutrients to grow and create new colonies. When…