Broken tooth provides the key to solving the riddle of Hatshepsut

In the end it was a tooth that clinched Egypt's biggest find of the century. Zahi Hawass, head of the Supreme Council of Antiquities, announced to the world yesterday that he had positively identified a mummy found in a tomb in the Valley of the Kings as that of Queen Hatshepsut.

He described the discovery as "the most important find in Egypt's Valley of the Kings since the discovery of Tutankhamun in 1922".

Hatshepsut came to power in about 1479BC after the death of her husband and half-brother Thutmose II. Her husband's son by a concubine, Thutmose III, was too young to rule, so Hatshepsut, the "foremost of noble ladies" (the meaning of her name), ruled as co-regent for about 22 years. But she was far from being a mere stand-in. She proved a forceful and ambitious ruler, one of the great builders of ancient Egypt and the ruler who did more than anyone else to make her country the wealthy kingdom it had become by the reign of Tutankhamun, more than a century later.

When she died in middle age, she left a magnificent mortuary temple, Deir el-Bahri, near the entrance of the Valley of the Kings, composed of a stepped series of colonnades. But her mummy was missing from it. Now Dr Hawass claims to have built on the efforts of the pioneering Egyptologist Howard Carter and found proof positive that a mummy found in a completely different place is that of Hatshepsut.

In 1903, in a tomb in the Valley of the Kings known as KV60, Carter found two sarcophagi, each of which contained the mummy of an unknown woman. One of the two was said to be Hatshepsut's wet nurse, the other was unidentified. Seventeen years later Carter went on to discover the tomb of Hatshepsut - but the two sarcophagi inside were empty.

Two months ago Dr Hawass went back to the KV60 sarcophagi and took them to Cairo's Egyptian Museum. He used CT scans to produce detailed three-dimensional images of the mummified women and compared them with the known physical traits of the queen, as preserved in numerous contemporary paintings.

Dr Hawass says earlier accounts of the two female mummies confused their roles and identities. One of the two had her right arm clasped over her breast - leading the Egyptologist Elizabeth Thomas to suggest many years ago that this might be the missing queen, as this is a posture often adopted by Egyptian royalty. But Dr Hawass claims that the mummy found in this posture is in fact the queen's wet nurse.

The crucial piece of evidence was a box containing a broken tooth, inscribed with the queen's name. Professor Yehya Zakariya, an orthodontics expert, checked the tooth against all possible Hatshepsut mummies and found that it fitted perfectly into a cavity in the upper jaw of the fatter of the two mummies from KV60. Hatshepsut was a fat woman who probably suffered from diabetes and liver cancer.

"The identification of the tooth with the jaw can show this is Hatshepsut," Dr Hawass told a press conference at the museum. "A tooth is like a fingerprint. It is 100 per cent definitive. It is 1.80cm [wide], and the dentist took the measurement and studied that part. He said he found it fit exactly 100 per cent with this part."

One Egyptologist, who declined to be named, told Reuters he was not totally convinced. "It's an interesting piece of scientific deduction which might point to the truth," he said.

Dr Hawass said he was doing DNA studies on the mummy.

In the past century Hatshepsut's image has been transformed from wicked stepmother, usurping the throne from her stepson Thutmose III (who after her death went to considerable lengths to destroy her memory), to feminist icon. She was the first female ruler in history to dominate her nation as securely as any male, enabling Egypt to recover from the disastrous Hyskos occupation, winning several wars, and sending trade missions to the land of Punt, now part of Eritrea.

But as a new exhibition at the Museum of Egyptian Antiquities in Turin reveals, she emerged from a society in which women were already accorded high status. Dr Sara Caramello, an Egyptologist at the museum, explained: "Women in her society were never treated as inferiors."