SERVICE FOR A SMILE - Visiting a middle school, a national nonprofit group and 12 local dentists provide free cleanings to children who can't afford routine dental care

Christina's Smile shows up on the faces of students like Genesis Sandoval.

The 8-year-old and other children received free cleanings, fillings and tooth extractions through Christina's Smile Children's Dental Clinic -- in a 48-foot semitrailer parked at Heritage Middle School in West St. Paul.

Volunteer dentists and their assistants expect to help improve the teeth of 80 District 197 students Wednesday and today. The benefits of proper oral hygiene will follow students into the classroom this fall, where health can affect learning the most.

"It's hard for kids to go to school when they're not taken care of," said Julie Ching, who teaches eighth-grade Spanish at Heritage. "This opportunity is a luxury for many families."

The families using Christina's Smile, a nonprofit founded by an Austin, Texas, dentist, are often more worried about paying rent, putting dinner on the table and paying bills on time, so visiting a dentist can become an afterthought for these families, said Ching, who helped organize the clinic.

Genesis saw a dentist more than a year ago and showed up at Christina's Smile with her 10th cavity.

"Would you like bubble-gum or regular toothpaste?" asked Dr. Darcy Rindelaub's assistant, as she prepared to clean Genesis' teeth. Lying still on a sea-blue reclined chair with her hands tightly clasped above her cargo pants, Genesis chose bubble gum as her flavor.

"They tried to kill my cavity," said Genesis, who attends Garlough Elementary. "I'm sure I'll feel better tomorrow."

Dental insurance is too expensive for Genesis' family. Her father does roofing and her mother occasionally cleans homes. Even the cheaper rates at the University of Minnesota's dental clinic are too pricey for regular visits.

More dentists should volunteer their skills to help needy children, said Dr. Richard Garza, who started the nonprofit and named it after his deceased daughter, Christina.

Garza, who will visit 22 cities nationwide this year, said Christina's Smile averages $25,000 worth of dental work a day. The 12 dentists volunteering in West St. Paul, the only stop in Minnesota, will contribute to the nearly $13 million in work done since the program's inception in 1990.

But finding volunteers can be hard. Christina's Smile is typically a three-day program, but there were only enough volunteers for two days in West St. Paul, Garza said.

For Dr. Michelle Meiser, volunteering meant shutting down her Coon Rapids clinic for most of the day.

"The atmosphere is fun here," Meiser said. "You're helping kids who need it the most."

Today's schools are concerned about students' overall health. Sick students fall behind, and schools lose money for each day a student misses school. More than 51 million school hours are lost each year to dental-related illness, according to a 2000 U.S. Department of Health and Human Services study. The same study reports that tooth decay is one of the most common chronic childhood diseases -- five times more common than asthma.

The sterile, plastic smell of a "normal" clinic lingered in the air at the three dental stations lined up in the narrow trailer. It was quiet except for the beeping machines, the swooshing of water being sucked out of patients' mouths and metal scratching against enamel.

Genesis said she hopes to see a dentist sooner rather than later the next time around, even though the bubble- gum toothpaste tasted like rotted onions.

"I was scared they would poke something, but now I feel a lot better," she said.