Prof Thomson is the primary supervisor of Lyndie Foster Page, Jonathan Broadbent, and Jennifer Doss, who will gain PhDs in dentistry today.
This is the first time any Otago dentistry staff member has been the main supervisor of three people gaining doctorates at the same ceremony.
It might also be the first time this has happened in any Otago University discipline.
About 580 graduands in health sciences, including dentistry, medicine and physiotherapy, will graduate in person at the Dunedin Town Hall at 3pm today.
This is the university's largest health sciences graduation, well up on the previous record, 565 in December 2008.
A record 66 people will also graduate with a doctorate, either in person or in absentia, at today's ceremony - well up from 34 last year.
Prof Thomson said it was "very satisfying" to see three people he had supervised completing doctorates in dental public health.
"I'm very proud of these outstanding young researchers," he said.
All three researchers had been "under the pump", facing many pressures and challenges before successfully completing their research.
Ms Foster Page, now a senior lecturer at the Otago school, and Mr Broadbent, a research fellow at the school, had both undertaken full-time work while carrying out their doctoral research, he said.
Miss Doss, a Malaysian-born researcher, whose research on aspects oral cancer in Malaysia involved travel to far-flung health centres, also had child-care responsibilities while studying.
She was supported by Otago University's inaugural Sulaiman Daud postgraduate scholarship.
University graduate research services director Dr Charles Tustin said today's graduation records reflected not only the university's overall student roll growth, but also an increasingly "research-intensive" approach.
About 1250 people were enrolled for Otago doctoral study this year, up from 1000 in 2007, he said.
Prof Thomson said there had been "an element of luck" in his supervisory record, given that the three researchers had begun their different projects about the same time and had opted to graduate at the same ceremony.
The doctoral trio yesterday praised Prof Thomson for his friendly and accessible approach.
Mr Broadbent said he was a "super supervisor" who had played a "key" role.
