For Harvard School of Dental Medicine (HSDM) student Ryan Lisann, completing one of the last requirements of his four-year D.M.D. program — a three-month externship at Charles River Community Health Center in Brighton — was an experience that will shape his career.

“I’m really passionate about education and wanting to work with kids, so getting to work in a community health setting and treating pediatric patients confirmed the path I want to take,” Lisann said.

“Seeing patients arrive at a clinic, particularly young children, with a mouth full of cavities is incredibly disheartening. It’s clear that education is part of the solution.”

Lisann hopes to use early childhood dental education to address disparities in oral health and fill gaps in care to lessen the need for fillings. After graduation, while his peers go on to residency programs and dental practices around the country, Lisann plans to work part time and pursue a master’s degree in education before applying for a pediatric dentistry residency.

On a recent Friday at Charles River Community Health Center, Lisann was treating 10-year-old Diego. Speaking reassuringly in Spanish to the young Venezuelan, Lisann explained the procedure he would be using to fill two cavities.

“The biggest thing is building trust,” Lisann said. “Many kids we treat here are seeing a dentist for the first time.”

The center serves a large number of recent immigrants from Central America. During his externship, Lisann spoke in Spanish to better connect with patients. He also developed techniques to build children’s confidence once they’re in his chair, like counting down and focusing on deep breathing before Lisann uses a needle to administer a shot of anesthetic. He tells Diego the sensation will be like a quick mosquito bite and asks him to give a thumbs-up to let him know he’s OK.

Fourth-year HSDM students like Lisann complete a community-based general dentistry externship to expand their perspective of oral health delivery systems, and build on their medical and dental knowledge by providing care in a community setting. Besides Charles River Community Health Center, other HSDM externship sites include Boston Health Care for the Homeless, Brookside Community Health Center, Community Health Center of Cape Cod, The Dimock Center, Edith Nourse Rogers Memorial Veterans Hospital, Harvard Street Neighborhood Health Center, Lynn Community Health Center, Mattapan Community Health Center, and the VA Boston Healthcare System.

A young boy and his dentist.
Harvard School of Dental Medicine student Ryan Lisann with his young patient, Diego.

Once on site, students collaborate with community dentists to develop treatment plans and treat underserved populations. HSDM students spend 12 weeks in each externship, twice the typical six-week externship at other dental schools, which gives them time to build a closer connection to the patients, dentists, and staff at the sites.

“We love working with HSDM students,” said dental director Janice Cho at Charles River Health. (She is also a lecturer at the School.) “We look forward to having the externs rotate through the health center as they bring a positive energy and provide compassionate care to patients who need it the most,” she said.

Charles River Community Health Center serves the communities of Allston, Brighton, and Waltham by providing comprehensive, coordinated care. The center’s roots are in Allston-Brighton, where it was first established as the Joseph M. Smith Community Health Center more than 35 years ago. Dental services have been offered since the beginning, and HSDM students have been part of dental care at the center for nearly 20 years.

“The aim of Charles River Community Health is to provide a dental safety net experience that externs hopefully enjoy, learn and grow from,” said Cho.

“There’s such a great need for community dental care in the U.S.,” Lisann said. “This experience has taught me so much and opened my eyes to areas where I can have the most impact.”