I knew a kid in high school who was missing his front tooth. He had to wear a retainer with a fake tooth, and that looked real, but sometimes he would take it out and have a massive whole in the front of his mouth. He was made fun of. A few years later I bumped into him in college and he had a permanent replacement tooth and it looked 100% natural. I assume boxers can just get the same, done. A permanent denture, or whatever the term may be, for whatever tooth was knocked out.
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