A former dentist in the U.S. has pleaded guilty to fraud for using paper clips instead of stainless steel posts in root canals.Michael Clair will be sentenced next Monday after pleading guilty last week in a Massachusetts court to a variety of charges, including defrauding a government health program of $130,000, assault and battery, illegally prescribing prescription drugs and witness intimidation.Authorities say instead of stainless steel posts for root canals, he used sections of paper clips — which can cause pain and even infection — in an effort to save money.Attorney General Martha Coakley says paper clips can sometimes be used temporarily, but the 53-year-old Clair used the paper clips as a permanent fix.