“This was a very complex study and we were surprised to see these outcomes, because when the standard therapy works so well, it creates a ‘ceiling effect’ whereby it is difficult to improve further,” says Professor Iain Chapple of the Periodontal Research Group at the University’s School of Dentistry, which led the study. “It is difficult to assess the size of the additional clinical benefit, because these patients were well nourished, and had the highest quality standard therapy anyhow. We are very interested in what the effects will be in people who are nutritionally depleted, and in those who do not or cannot access high quality gum care.”