SAN DIEGO -- Brushing at least twice a day is the best way to keep your child's teeth clean. But there are steps you can take to keep them from getting too dirty in the first place. They include fluoride varnishes and dental sealants.

Flo Clarke was looking for a dental treatment for her two girls, Sascha and Solange. She cannot afford to take her girls to their regular dentist for these expensive options, so she signed up for a free clinic held at Southwestern College.

Clarke said she has tried everything to keep her girls' mouths healthy, but admits, it can be a challenge.

"My youngest daughter, unfortunately, has my teeth," Clarke said. "There are a lot of 'nooks and crannies' in there and she has an enormous sweet tooth, so she does have two cavities."

At the clinic, a dental hygienist varnished Sascha and Solange's teeth with fluoride, to help harden the enamel.

The girls also had a several teeth sealed, to protect the biting surfaces. The hygienist explained the sealant is a plastic covering that fills the top of the teeth so food can't get trapped, allowing cavities to start.

For Clarke, the opportunity to get sealants and fluoride varnishes for her daughters was worth the wait at the busy clinic.

"It's not an absolute measure against cavities but it definitely is a very wise thing to do as far as preventative measures," Clarke said.

The next free dental clinic at Southwestern College is coming up this spring.