Japanese researchers have developed a groundbreaking drug that can regrow teeth. The drug targets a protein that inhibits tooth growth and has shown promising results in mice and ferrets.

And it’s not.” The box was opened. What he saw inside — two yellowed teeth from a long-dead mastodon — stirred in Dr. Harris a thrill he hadn’t felt in years. “I was crazy excited ...

But after picking them up, it became clear they were something much rarer: giant fossil teeth. The homeowner—who, according to the Associated Press, wishes to remain anonymous—alerted the ...