Stemming dental disorders

Simon Tran

Thirteen years ago, Simon Tran packed his dentist kit and left Montreal in search of new research opportunities. This summer, Tran returned to Montreal not only with impressive research experience under his belt — a PhD in oral biology from the University of Minnesota, and post-doctoral experience at the National Institutes of Health (NIH) — but also with a new wife.

Claudio Calligaris

"I grew up in Quebec," said Tran. "I knew one day I would return to my family and roots."

Everything seems to have fallen in place for Tran, who was recently appointed to the Faculty of Dentistry. He teaches and practices dentistry at McGill, but most of his time is reserved for pursuing his true passion — research.

Tran is looking at the therapeutical potential of adult stem cells to treat oral health disorders such as loss of salivary glands and periodontal disease. It was originally believed that unlike immature stem cells, adult stem cells could not be reprogrammed to become any cell — once committed to a specific tissue, that was where they would stay (for instance, an adult stem cell in the brain would become a brain cell). Tran, while at the NIH, discovered that this was not true for all adult stem cells. He, with his colleagues, showed that some adult bone marrow stem cells turned into cheek cells.

"This was an exciting find for us," said Tran. "It means that adult stem cells can be harvested and used to replace deficient or missing organs."

He is testing this theory in the mouth. With support from the Canada Foundation for Innovation New Opportunities Fund, he is looking at using stem cells to replace salivary glands that have been destroyed following chemotherapy, or that are non-existent due to a disease called Sjogren's Syndrome. In both cases patients have difficulty swallowing and eating due to the lack of saliva. Tran hopes to seed newly grown salivary cells into the patient's mouths on a thin tube. Eventually, the cells will flourish and secrete the much-needed saliva.

"At the moment there are few treatment options available for these patients, who often have a poor quality of life," said James Lund, McGill's dean of dentistry. "This research may offer them a chance of a normal life."

Tran would also like to use adult stem cells to treat periodontitis, a disease that affects the gums, bones around the teeth and the teeth. Tran is hopeful that stem cells may be used one day to rebuild these affected areas and to restore quality of life for these individuals.

Christine Zeindler