John Albert Pedler was a professor of oral medicine and pathology and head of the department of oral diagnosis in the faculty of dentistry at the University of Toronto, Canada. He was born in Wood Green, north London on 30 December 1920, the son of Samuel Pedler, a clerk in the architects’ department of London County Council, and Ada Blanche Pedler née Palmer. He began training as a dentist in 1937 at the age of 16 and qualified with his BDS in 1941. He was a house surgeon at the London Hospital and then, from August 1942 to 1947, a dental officer in the dental branch of the Royal Air Force. Following his demobilisation, he completed his medical training and gained his MRCS LRCP in 1950. From 1950 he was a senior registrar at the London Hospital’s dental school and, from 1951, a senior lecturer in dental pathology at the London Hospital medical college. In 1961 he moved to Toronto, Canada, as a professor of oral medicine and pathology at the University of Toronto. He was also dental surgeon in chief at Toronto General Hospital, where he was described as ‘the architect of hospital dentistry in Toronto and at Toronto General Hospital in particular’. Working with the department of cardiac surgery and cardiology, he introduced dental screening for all pre-surgery patients to identify bacteria and gingivitis, which could lead to post operation infections and fatalities: deaths due to infections were successfully reduced to zero. In his private practice he gave free services to the financially insecure and provided treatments and procedures to patients with haemophilia. Pedler died peacefully in Sunnybrook Hospital, Toronto, on 2 February 2018 aged 97. Predeceased by his wife Joan (née Steedman) in 2008 and his daughter Trisha, he was survived by his son, Trevor, and daughter, Carole, four grandchildren, Shauna, Jessica, Michael and Christine, and two great grandchildren, Luke and James.