How George Washington’s Bad Teeth Helped Win the Revolutionary War

As he aged, George Washington gradually lost his teeth. Throughout his life, he consulted a variety of dentists to provide dentures for him.
In 1781, General Washington commanded the army watching over New York City, then occupied by the British. General Cornwallis was then campaigning in the South. For a brief time, a French fleet and army would be available to assist the Americans, so Washington and the French General Rochambeau planned to jointly march to Virginia to attack Cornwallis. At the end of this campaign, Washington scored his greatest victory by forcing Cornwallis to surrender at Yorktown.
Washington’s bad teeth helped the Americans win that battle at Yorktown.
While he remained encamped outside of New York City, the British captured a packet of Washington’s letters. One of them was a letter to a dentist in Philadelphia. Washington mentioned that he would probably not be able to come to Philadelphia and asked the doctor to send him a tooth scraper.

Washington would not be able to come to Philadelphia because he would be fighting in Virginia. But General Clinton, the British commander in New York City, interpreted the letter to mean that Washington would remain encamped outside of New York City. John L. Smith, Jr. writes in the Journal of the American Revolution:

After verifying that the intercepted mail was real and not a set-up, the British Army commander in America, Sir Henry Clinton, became convinced that Washington and his army was going to stay put the Hudson Highlands north of New York City. Clinton let his guard down.
Little did Clinton know that just after Washington had written the tooth-scraping letter, both Washington and Rochambeau began planning the Franco-American armies’ movement down to Virginia – down to meet General Cornwallis at Yorktown for the siege that basically ended the Revolutionary War.

A webpage maintained by Mount Vernon confirms this claim.