Each year for her vacation, Karen Miller, a staff dentist at Penn's Dental Care Center, heads down to tropical Brazil for two weeks.

Instead of soaking up rays on the beaches of Rio, though, she provides dental care for orphans and the poor in the northeastern coastal city of Fortaleza.

Miller is part of a team of dentists that practice "missionary dentistry" -- the provision of free dental care to those in need. As the term suggests, the dentists work through arrangements with a church -- in this case, the First Presbyterian Church of Fortaleza, which provides housing and local transportation for the dentists.

Miller's involvement in missionary dentistry extends back to her days as a University of Maryland dental student. After her postgraduate residency at Penn, she spoke with a friend, Therese Brennan (now in the Department of Oral Surgery at the Dental School), who had heard about her work and had the opportunity to become involved in the Brazilian project. In 1994, they together organized the trip.

Each year, Miller said, "We travel to places where we can gather kids who couldn't afford dental care." The dentists perform routine care -- fillings, extractions and infection control.

While the procedures performed are routine, she added, "the challenge of this kind of dentistry is the compromised conditions " -- working in the tropics in mobile clinics where "climate control" means opening a window and with equipment designed principally for easy transport.

The dentists also faced a more unusual challenge: convincing the locals that an all-female dental team could run an entire clinic. "So far, our teams have been all-female," Miller said, "which is interesting because the Brazilians would always ask 'Who's in charge?' and we'd say 'We are.' They found it surprising at first, because Brazil is a male-oriented culture."

Miller plans to return to Fortaleza next January, and will take "anyone who's willing to work and is interested in coming." Anyone interested may call Miller at the Dental Care Center, 898-4615.