NATCHEZ — It is popular to say the family business is in the blood, but for the O’Brien family it is actually in the enamel.

Three generations of the O’Brien family have followed the same path to become dentists — a tradition that began when William T. O’Brien Jr. completed dental school and set up a practice in Natchez shortly thereafter.

O’Brien, now 94, practiced dentistry for 44 years in Natchez beginning in 1946. For many years his office was set up in his downtown house, where he balanced his life as a dentist with his life as a father to six children.

Now the O’Brien family legacy is being carried on by his son Dr. Tommy O’Brien and grandchildren Dr. Brennan O’Brien and Bridget O’Brien Henson.

Brennan O’Brien completed dental school in May and Bridget O’Brien Henson is in her fourth year of dental school.

Tommy O’Brien’s wife Barbara is also a registered dental hygienist.

Today, as the family celebrates Father’s Day together, it is a sure bet the topic of teeth will come up, but the focus will likely be on carrying on the tradition of compassionate dentistry started with William O’Brien.

When William O’Brien began dental school in 1941 he never thought he would begin a family legacy that would be going strong nearly 70 years later.

Instead, he wanted a career that would be rewarding personally and professionally, and he found that at a shoe store in his hometown on the Mississippi Gulf Coast.

“I was talking to a gentleman who was a dentist there, and he was telling me about it,” William O’Brien recalled. “I guess you could say he talked me into being a dentist.”

After that chat, he enrolled in classes for one year at Ole Miss before transferring to Loyola University in New Orleans for one year of pre-dentistry education and then entered dental school in 1941.

“Back then you were taught to do dentistry standing up,” O’Brien said. “Doing that for 40 years can be hard on your old body.”

But the physical pain that came from standing, stooping and bending over patients for long hours, never deterred O’Brien from continuing to practice. It was, he said, the relationships he built with patients that kept him practicing.

“Having a dental office in my house, everyone knew I was there,” he said. “If someone had a toothache or something in the middle of the night, they’d just come over to the house and ring the bell.”

And O’Brien always answered and always helped.

It was that side of the job that really stuck with O’Brien’s son, Tommy O’Brien.

“Seeing how he built relationships with patients really influenced my decision to enter the field,” he said. “Now that I’ve had my practice, my patients aren’t patients anymore. They are like an extension of my family.”

Natchez, in a way, is lucky to be the home of the O’Brien dental legacy. When looking for a place to set up his practice, William O’Brien just started driving with his wife.

“We just traveled north,” he said. “We stopped here off of (U.S. 61), and I talked to Dr. Gaudet and he said the town could really use another dentist. I started here and never thought about leaving.”

Growing up in right outside his dad’s office door, Tommy O’Brien was able to get an up close look at his dad’s practice, but what he remembers most from that time was how nice it was having his dad around the house.

“Coming home from school, he was always there,” Tommy O’Brien said. “He always made a point to be at whatever activities we were doing in our childhood. I don’t think at the time I realized what a luxury it was to have his office right there.”

But for William O’Brien there was never a question about balancing his home life and his work life — it was a decision he made from the first day he opened his home office.

“When I was at home I closed the door to the office and never looked back,” he said.

While growing up, the dentist office was mostly a child-free zone, but once Tommy O’Brien entered dental school he did get a little hands-on training.

“There was one instance where I needed a gold inlay for one of my teeth and dad actually let me make it in the lab and then he cemented it in,” Tommy O’Brien said.

Sitting in the modern office of Tommy O’Brien, William O’Brien said much has changed since his days of dentistry. He said during his practice there were no rolling stools or extra hands.

“We learned to do it all on our own, and even after assistants came around, I still just kept doing it all,” he said. “I guess I was stuck in my ways.”

For Tommy O’Brien there is no doubt about his father’s influence in his career choice and no greater dentist he’d rather emulate.

And it seems he is having that same effect on his own children.

Bridget O’Brien Henson said she was undecided for a while about her career, but the pull to dentistry was too strong to ignore.

“I’ve always been interested in art and the fact that dentistry has many aspects of art to it was really appealing,” she said. “I am very proud to be following in the footsteps of my (father and grandfather).”

For Bridget Henson, her professional path is following her father’s and grandfather’s almost step-for-step.

After completing dental school, she will enter the U.S. Navy and serve as a Navy dentist, just as her father and grandfather did.

“They were both stationed on bases in the Philippines,” she said. “Unfortunately, there aren’t bases there now so I can’t be stationed there as well.”

Brennan O’Brien, who will soon begin a dental residency in Baton Rouge, said he knew he would be following his father and grandfather.

“In high school and maybe before I knew I wanted to pursue dentistry,” he said. “Dad never tried to persuade me or dissuade me, but seeing him coming home from the office and how rewarding it was for him, there was never much doubt that I would do this, too.”

And now that Brennan has completed dental school, he knows he has a trusted source for advice.

“There is no other dentist that would give me as honest or thorough advice than my dad,” he said. “I’d trust no other dentist as much as I trust my dad.”