A study suggests that curbing the routine use of preventive antibiotics before dental work may have contributed to a rise in heart valve infections in England.

Some dental procedures can let bacteria from the mouth enter the bloodstream, travel to the heart and cause an infection. It used to be routine to give people at high risk for this problem a single antibiotic pill just before dental work, but concerns about overuse of antibiotics led British regulators to end this practice in 2008.

The study found that heart infections rose afterward, but it does not prove that fewer antibiotics is the reason.

In the U.S., patients at highest risk of heart complications still get preventive drugs before dental work.

The study was discussed Tuesday at an American Heart Association conference.