A group of 37 doctors, nurses and technicians, many from the Yale School of Medicine or Yale-New Haven Hospital, put a smile on the faces of about 150 children in rural Thailand last month.

The team of anesthesiologists, plastic surgeons and their support crew, working with the California-based group Interplast, went to Thailand late last month to operate on children with birth defects such as cleft palettes and lips, drooping eyelids, deformed ears and untreated burn scars.

Although the medical school and Yale-New Haven did not sponsor the trip, they did provide the team with supplies, sterilized equipment and other provisions.

Many of the participants have previously taken part in surgery trips to developing nations, and said, although demanding, the trip was rewarding.

“The best part for me was when I got to present the governor of Thailand with money that Wallingford Elementary School children raised, which amounted to about $212,” John Tangredi, the trip’s head nurse, said. “Then I took it directly to principals of schools and made sure it went to the children of Thailand.”

Yale-New Haven plastic surgeon Stefano Fusi said the most meaningful part of his trip was in the operating room.

“The most important aspect to trips like these is seeing the children,” Fusi said. “It is by far the most rewarding part.”

The Thai medical infrastructure, as in many developing countries, does not allow for all children to have their birth defects fixed at a young age. Fusi said health care and services like reconstructive surgery are not widely available to indigenous people, such as those that he and his team operated on.

The children were picked for surgery based on age and gravity, and the cases with highest priority usually involved younger patients and more severe defects. The most severe cases may be brought to the United States in the future for further treatment.

This trip had been planned since last May, well before last December’s deadly tsunami. Although the focus of the trip was providing care to indigenous children with birth defects, five of the participants, including Tangredi, had the opportunity to devote some time to the tsunami victims.

“We gave 70 poor families enough money, raised here at Yale, to eat for four months,” Tangredi said. “You can’t imagine what the scene looked like — a town so wiped out by the wave, it was barely there.”

The next surgery trip will be to Honduras next May.