Speaker 1: Welcome to brain Stuff from house stuff works dot com
Speaker 1: where smart Happens hi Immercial Brain with today's question, what
Speaker 1: is a cavity in a tooth and why do they
Speaker 1: drill it? There are three parts to any tooth. There's
Speaker 1: the outer very hard enamel. There's the inner much softer denton,
Speaker 1: which is like ivory, and then there's the core pulp,
Speaker 1: consisting of nerves and blood vessels. When you get plaque
Speaker 1: on your teeth, what you're getting is a film of bacteria.
Speaker 1: These bacteria stick to your teeth, and one of the
Speaker 1: things they do is create acid as a byproduct of
Speaker 1: their metabolism. The acid can eat through the enamel of
Speaker 1: the tooth and cause a cavity, that's a hole through
Speaker 1: the enamel. Once the acid breaks through the enamel, bacteria
Speaker 1: invade the denton and can start to eat through it
Speaker 1: fairly quickly if they make it to the pulp. That
Speaker 1: is when you get a tooth infection, and then you
Speaker 1: need a root canal. When a dentist drills a tooth,
Speaker 1: what he or she is doing is shaping and opening.
Speaker 1: The first reason to do this is to make sure
Speaker 1: that all the rot in the denton is completely removed.
Speaker 1: The second reason is to create a shape to which
Speaker 1: the filling can bond and feel completely. For more on
Speaker 1: this and thousands of other topics, does it how stuff
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