Thomas Anderson Hunter was born in Dunedin, New Zealand, on 10 February 1863, the son of Scottish parents Mary Sim and her husband, Alexander Hunter, an engineer. He trained under the apprentice dentist system with Alfred Boot, one of Dunedin's most successful dentists. Already in practice by the age of 17, Hunter registered in May 1881. He travelled as far as Invercargill and Lawrence, where he and Boot spent much time repairing the damage wrought by rough tooth-pullers. Hunter also worked with Boot, Frank Armstrong and other progressive Dunedin dentists to help provide extra instruction for their younger colleagues and so raise standards. But the situation remained hopeless, with the first attempt to establish a dental association in 1889–90 proving a failure. Standards of training and practice remained low and quackery was still commonplace into the new century.
The cause of progressive dentistry only advanced from 1903 when Hunter and other Dunedin dentists won the support of the Liberal MHR for Caversham, T. K. Sidey. They persuaded Sidey that standards could only be improved if dentists were trained to university level and entrance criteria into their profession were tightened. Sidey's new Dentists Act was passed in 1904, the second New Zealand Dental Association was established in 1905 to oversee its implementation and the Dental School was established at the University of Otago in 1907. It was based in Dunedin, reputedly because Hunter and others had persuaded Premier Richard Seddon that the city had the climate most suited to scholarly endeavour. Hunter helped see through these developments as second president of the NZDA. He also made clear his commitment to the new training institution by guaranteeing £1,000 to ensure that the Dental School was built.
Reform took time and Hunter and the NZDA still had a problem with unqualified dentists gaining entry to the profession. However, H. P. Pickerill, as foundation director of the Dental School, insisted that the highest standards were maintained, and with the backing of Hunter and the NZDA he ensured that New Zealand dentistry developed independently of the dominance of the medical profession or dental mechanics. Meanwhile, Hunter gained in remuneration and status; by 1903 he resided in the élite area of Heriot Row and in 1905 he was vice president of the exclusive Dunedin Club.
When soldiers were recruited for the First World War, about 60 per cent of men had to be sent for dental repairs. Hunter, as chairman of the executive council of the NZDA, proposed in June 1915 that a civilian corps be established to perform work at cost. This scheme, under the guidance of Hunter and Pickerill, proved so useful that a full New Zealand Dental Corps was established in November 1915. Hunter was placed in charge of its operation and given the rank of lieutenant colonel. He worked mainly from New Zealand but travelled to Britain in late 1916 to oversee the establishment of dental units on the western front. He insisted that the corps remain independent from the New Zealand Medical Corps. For his efforts he was later promoted to the rank of colonel.
Hunter's experiences in the Dental Corps persuaded him that something dramatic had to be done to improve the dental health of future generations. Once he was appointed to the post of director of the new Division of Dental Hygiene within the revamped Department of Health, he proposed his solution of establishing a school dental nurse service, which was to constitute his greatest contribution to the development of New Zealand dentistry.
Hunter was a close friend of child health reformer Truby King, who had initiated the Plunket nursing system. Greatly admiring the work of these nurses, he based his dental nursing proposal on this model. He argued that women were better suited than men to working with children, and added that such a scheme would be far cheaper than training more dentists. Pickerill and others expressed concern that standards of dental care and the development of the dental profession would be undermined, but Hunter won the day because the cheapness of the scheme appealed to politicians.
His initiative helped to keep women out of dentistry until the 1970s: its emphasis on women's traditional role and the provision of a job between school and marriage proved popular. Hunter promoted the service with enthusiasm and got it away to a sound start. He was knighted in 1946 for his work as foundation director and celebrated by donating £1,000 to the Dental School for research purposes.
Three years before he retired, on 6 September 1927 at Trentham, Thomas Hunter married Greta Ewen; he was 64 and she was 24 years his junior. He died at Heretaunga at the age of 95 on 29 December 1958, survived by his wife. His long career in dentistry had seen major advances in dental care and a shift from the apprentice system to full professionalisation. His dental nursing scheme later influenced developments in more than 15 countries. Latter-day opinion of its worth is divided and some believe that Hunter wanted to keep women out of the mainstream of the dental profession. However, he can be credited with introducing a novel and distinctive experiment in public health care which became an integral part of the New Zealand childhood experience.