by Greg Thompson

Hyun-Duck Nah, DMD, MSD, PhD, shares her passion for craniofacial research

Take away the technological trappings, and Hyun-Duck Nah, DMD, MSD, PhD, believes that the core of the profession is less about moving teeth and more about changing lives. Faced early on with the case of a young boy with a serious overbite, she saw the power of orthodontics. “I did not just change his teeth—I changed him,” says Nah, who now serves as research director and associate professor in the Department of Plastic and Reconstructive Surgery in the University of Pennsylvania School of Medicine at The Children’s Hospital of Philadelphia.

Years ago, as a newly minted dental school graduate out of Seoul National University in Korea, the 24-year-old Nah set out for America to continue her education. With an impressive resume, she had her pick of colleges, and eventually settled on Case Western Reserve University (CWRU) in Cleveland. The decision was anything but random—Nah wanted to study under Donald Enlow, PhD, the former acting dean and Thomas J. Hill Distinguished Professor Emeritus from CWRU’s School of Dental Medicine, and author of the Handbook of Facial Growth, a tome still used in orthodontic education.

While Enlow was not an orthodontist, he was a world-renowned biologist and expert in craniofacial development. “I was always fascinated by how the face grows and develops,” says Nah, also an adjunct clinical associate professor in the Department of Orthodontics at Philadelphia-based Temple University. “I had braces when I was young, and it had an impact on me. I went to dental school to be an orthodontist from the get-go, and I wanted to study craniofacial growth, and that was where my heart was.”

After earning her orthodontic degree at CWRU (in addition to a DDS in Korea and a DMD at the University of Pennsylvania), Nah continued with her PhD education at the University of Connecticut. Despite the existence of several PhD/DMD combination programs, the additional doctorate is still somewhat rare. Among a pool of 250 graduates per year, Nah says it is reasonable to expect only about five or fewer to also put in the extra work for the PhD.


Name: Hyun-Duck Nah, DMD, MSD, PhD

Specialty: Orthodontics/Craniofacial Biology Research

Years in academics and practice: 17

Days in private practice per week: 1

Web site:


  • Research director and associate professor, Department of Plastic and Reconstructive Surgery, University of Pennsylvania School of Medicine, The Children’s Hospital of Philadelphia;
  • Adjunct clinical associate professor, Department of Orthodontics, Temple University, Philadelphia;
  • Co-chair of the Doctors’ Scientific Program for the AAO’s 2010 Annual Session;
  • Member of the AAO Council of Scientific Affairs;
  • Member of the planning and awards review committee for the American Association of Orthodontists Foundation; and
  • President-elect of the Craniofacial Biology Group, International Association for Dental Research.

The relatively low number reflects a nationwide shortage of orthodontic educators that has been an issue for at least the last decade. Most new orthodontists seek the higher compensation and added patient interaction of private practice, and those who opt for academics often encounter challenges they never imagined.

Accentuating the Academic

As cochair of the Doctors’ Scientific Program for the American Association of Orthodontists’ (AAO) 2010 Annual Session in Washington, DC, Nah hopes to address what she calls the “slow drainage” of professors from universities across the country. While she is responsible for just one section of a large conference, Nah hopes it will raise awareness and at least help to retain the educators who are already in the classroom. “It can be challenging to be in an academic institution, because there are a lot of demands,” laments Nah, who also knows the rigors of private practice as a 1-day-per-week orthodontist at Chester Springs Orthodontics PC, Newtown Square and Exton, Pa, a business she runs with her husband, K. Robert Cederquist, DDS, PhD. “At this year’s annual meeting, we will have a workshop to encourage educators and show them how to stay and be successful in academics. It is just one afternoon session, but I felt strongly about it. We are going to invite all junior faculty in all orthodontic departments to come and share their issues. We are doing this because orthodontic education is at risk, because we are losing more and more professors.”

For private practitioners looking to go from small business owner to university professor, Nah recommends staying in front of the technology curve, because staying up to date can be difficult for orthodontists in the thick of the daily grind. Seeking out part-time teaching stints is also a great way to connect with students. In addition to his full-time practice, Nah’s husband does exactly that—lecturing on facial growth and development to dental students at the University of Pennsylvania.

Invited by session organizers for her considerable scientific credentials, Nah hopes to bring an evidence-based practice philosophy to all facets of this year’s science track. With the help of Stephanos Kyrkanides, DDS, MS, PhD, who is a professor and chairman in the Department of Orthodontics and Pediatric Dentistry at the State University of New York, Stony Brook, School of Dental Medicine as well as cochair of the Doctors’ Scientific Program, Nah decided that attendees will no longer find a separate section on evidence-based practice. Instead, all speakers will present content that is based on evidence. “Speakers will be preparing their materials in a different way with that in mind,” Nah says. “Dr. Kyrkanides and I want more science behind all the topics. This is a continuation of a trend that we are implementing.”

Whether they come from the classroom, the clinic, or both, Nah hopes the educators of tomorrow will shine at this year’s AAO Annual Session, which takes place April 30 to May 4. With some of the well-known “stars” of the profession announcing retirement or getting closer to it, she and Kyrkanides decided it was time to give some of the younger orthodontists a chance at the spotlight.

In pondering these future stars, Nah acknowledges that there may be a vacuum felt at the top while new speakers develop the necessary reputation to pack lecture halls. “We must start to look for new talents, so we are giving opportunities to young orthodontists who have earned a chance by doing an excellent job,” Nah says. “We are cultivating some of the new generation who will shape the profession, and putting them into the main circle. Some of the well-established names declared that they are retiring this year. We still hope they will stick around, but in the national forum, it will be fantastic to give some young people a chance to become future speakers. It’s a chance we are taking, but I think it’s important.”

“Orthodontic education is at risk, because we are losing more and more professors,” Nah says.

In a nod to an ever-changing technological environment, each day of the session will be packed with hands-on courses. “When the new technology comes in, it requires a steep learning curve,” Nah explains. “Practicing orthodontists are typically outside of the learning environment, and sometimes they have a difficult time catching up. It is extremely important for AAO to be the place where orthodontists can go where they do not have to pay a lot of money or ultimately go somewhere else.”

Making Faces

While private-practice owners concentrate on day-to-day challenges, Nah hopes to directly test hypotheses born from clinical problems in the laboratory and lay the foundation for new technologies that can be applied to patient care. One specific aspect of Nah’s research is to investigate how the macroscopic process of craniofacial growth and development is determined at the molecular and cellular levels. This endeavor requires not only a basic science approach, but also knowledge pulled from clinicians who take care of patients with various craniofacial malformations—including orthodontic problems.

With 22 bones in the skull, all interconnected through sutures and joints, it is no small task. Specifically, Nah is interested in how these interdependent mechanisms work together to develop the face. “This means that a gene involved in the fate of a cranial suture, remote from jaw bones, could have a significant impact in the development of malocclusion—and it does,” Nah posits. “It is important that the structure in the top of our head forms normally to get a good dental occlusion. It goes all the way down to the genes, DNA, and proteins. This is a passion in my research.”

Ultimately, that research is built around the strengths of clinical practices at the University of Pennsylvania hospital and the Children’s Hospital of Pennsylvania. “The other side of my research is to develop innovative therapies for craniofacial and dental disorders, using cell- and gene-mediated approaches and tissue engineering,” Nah adds. “Examples of ongoing studies are to design an artificial bone construct that easily assimilates into real bone and grows with a patient with cleft palate, or a dental implant with engineered periodontal ligaments to allow orthodontic tooth movement in young patients with missing permanent teeth.

“Dental implants as they are now can’t be used in children, because once the implant is anchored, it can’t grow with the bone,” Nah continues. “As the bone grows, it slowly becomes submerged into bone, causing more problems. Children with missing teeth have deficient bone growth, which leads to a lot of problems later on. We need a way to add functional periodontal ligaments on dental implants, so that we can move those implants using orthodontic appliances to help the problem of missing permanent teeth—particularly for a patient with few teeth or no teeth. I am seeing more of these patients because I am in an environment where people are coming in with these serious problems.”

From Science Fiction to Clinical Fact

In her youth, Nah learned to love science by reading science fiction books. She has spent the last 17 years on the research front, and her cutting-edge work at the cellular and genetic level mirrors just how far technology and medicine in general have come. From a cultural standpoint, the profession has also progressed. After all, Nah was only the second woman to graduate from Case Western’s orthodontic residency program. “I had to come all the way from Korea to fill the second female slot at Case Western,” she says with a chuckle. “But all this is rapidly changing. In dental schools now, there are often more female students than male students. In Korea, where I am from, it was definitely a male-dominated profession. When I came here, I was actually surprised that there were a lot of female dental students.”

Nah’s research includes designing “an artificial bone construct that easily assimilates into real bone and grows with a patient.”

Fueling this trend is a realization that orthodontics is truly a lifestyle profession. Practitioners rarely have to be on call, and emergencies are rare. “Certain specialties, such as orthodontics, go well with a lifestyle,” Nah acknowledges. “This is attractive for women coming up.”

For Nah, the academic lifestyle has proven to be exceptionally busy, particularly in the past few years. It all leaves little time for hobbies. Instead, when she can grab some free time, she says, “My husband and I love to hang out with our two children. One just graduated from college, and the other is a senior in high school.”

Eventually, the countless hours writing grants, editing manuscripts, and peering over microscopes come back to cases such as the adolescent with the class II malocclusion that Nah treated so long ago. Before treatment, Nah reports that the boy rarely opened his mouth. He was extremely shy, had long hair and large spectacles, and his face could scarcely be seen. “In less than 2 years, you would not have recognized him,” Nah says. “Beyond just his teeth, his attitude changed, and I will never forget that. He got rid of his glasses, and he spoke with confidence and a smile. Orthodontics is much more than superficial, and it is truly a blessing to be in this profession.”

Greg Thompson is a contributing writer for Orthodontic Products. For more information, contact