People who have their teeth scraped and cleaned had lowered their heart attack and stroke risk by 24 and 13 per cent respectively, compared to those who never had a dental cleaning. These findings are based on a Taiwanese study of a database of more than 100,000 people who underwent dental cleaning and were followed for an average of seven years. Scientists considered tooth scaling frequent if it occurred at least twice or more in two years; occasional tooth scaling was once or less in two years. "Protection from heart disease and stroke was more pronounced in participants who got tooth scaling at least once a year," said Emily (Zu-Yin) Chen, cardiology fellow at the Veterans General Hospital in Taipei, Taiwan, who co-authored the study. Professional tooth scaling appears to reduce inflammation-causing bacterial growth that can lead to heart disease or stroke, she said, according to a Veterans Hospital statement. The study included more than 51,000 adults who had received at least one full or partial tooth scaling and a similar number of people matched with gender and health conditions who had no tooth scaling. None of the participants had a history of heart attack or stroke at the beginning of the study, under the Taiwan National Health insurance data base, the source of the information used in the analysis. In a separate study, researchers found a big difference in heart and stroke risk based on the number of remaining teeth. Anders Holmlund, Centre for Research and Development of the County Council of Gavleborg, Sweden, and senior consultant (specialized dentistry) studied 7,999 participants with periodontal (gum) disease and found people with fewer than 21 teeth had a 69 per cent increased risk of heart attack compared to those with the most teeth. A higher number of deepened periodontal pockets (infection of the gum around the base of the tooth) had a 53 per cent increased risk of heart attack compared to those with the fewest pockets.