So you would automatically extract an abycessed tooth instead of treating with antibiotics and then doing a root canal treatment?
I should have phrased that differently. If the determination was already made that the tooth was going to be extracted, and the patient had significant swelling and pain, I'd want to get it out as soon as possible. An abscess can vary a lot in severity, but the preferred treatment for a periapical abscess (what people are generally talking about when they say "abscessed tooth") is usually a root canal. With swelling, the main concern is that it will start to affect the airway, but the risk of systemic effects is a concern too. Because these things can flare up pretty quickly, if you know you have a dental abscess and you start having trouble breathing, you need to get to the ER asap.
About antibiotics, their purpose is to prevent the infection from going systemic, and start to reduce the swelling (which is a sign that the infection is starting to affect the soft tissues around the tooth). The source of the infection is inside the tooth, and because the tooth has a relatively limited blood flow, antibiotics don't get into the tooth in significant enough amounts to reduce the infection. The purpose of a root canal is to physically remove the infection and sterilize/seal off the inside of the tooth.
