A 30-year-old man, Zhang Binsheng, from the city of Harbin in China, went to the hospital last week after suffering from a severe case of blocked nose for three months.
He was shocked to discover that the blockage was caused by his own long-missing tooth which was knocked out during an accident when he was 10 years old.
The strange growth, called an intranasal retained tooth, can be caused by physical damage or developmental problems.
Having a tooth growing in one's nostril is rare and thought to affect somewhere between 0.1 per cent and one per cent of the population.
Mr. Zhang had two teeth knocked out of him in 1999 as a child after falling from the third floor of a mall. He said he only managed to find one broken tooth after the accident.
About three months ago, Mr. Zhang came down with a cold and his nose was blocked.
His condition was so serious he had trouble breathing and could not sleep properly at night.
He went to seek medical advice.
During an X-ray check, doctors noticed a shadow 'with high density' at the back of his nasal cavity.
Dr. Zhou Bin, a director at the department, suspected that the tooth had been uprooted during the accident and pushed into Mr Wang's nostril by the impact of the fall, it had then somehow managed to root and grow in the patient's nose.
Mr Wang's doctor-in-charge, Guo Longmei, said because the tooth belonged to the man, his nose had not rejected the 'foreign object', leading it to go unnoticed for two decades.
Medics removed the tooth, which measured nearly one centimeter (0.4 inches) long, from Mr Wang's nose in a 30-minute surgical operation last Friday.