Fillings are great for fixing cavities but certain types might lead to surprising problems in kids.

More than half of American children have had a cavity by age 7. These days, more kids are getting fillings made of a tooth-colored composite instead of silver mercury fillings.

A chemical called BPA which has been linked to health concerns is sometimes used to make these composite fillings.

In a new study, published in the journal Pediatrics, researchers collected treatment data from more than 500 children seen at several community dental clinics.

The children were all 6 to 10 years old at the start of the 5-year trial.

Psychological assessments were made at the beginning and at completion.

The findings:

Composite fillings that contained the material related to BPA were linked to anxiety, depression, social stress, and other problems. These issues weren't linked to mercury fillings, however.

The next time a cavity strikes your child, talk to your dentist about the benefits and possible concerns that may come with different types of fillings.

I'm Dr. Cindy Haines of HealthDay TV, with the news that doctors are reading; health news that matters to you.