‘Living legend’ Dr. Ray Bowen retires after 62 years
December 18, 2018
Honored: Dr. Ray Bowen, right, receives the 2014 American Association for Dental Research Distinguished Scientist Award in 2014.
“To me, he is a living legend.”
That’s how Jirun Sun, Ph.D., senior project leader at the ADA Foundation Volpe Research Center, describes Dr. Rafael “Ray” Bowen, who retired in 2018 after 62 years at the ADA. But he’s not legendary because of his service with the Association.
In 1962, Dr. Bowen developed Bis-GMA, a methacrylate monomer used in most modern composite resin restorative materials, while at the ADA Research Unit at the National Bureau of Standards. Bis-GMA has been the most used resin in dental restoration for more than 50 years, transforming the process in dentistry, according to Dr. Sun.
“Through over six decades of his research career, Dr. Bowen has worked on methods for reducing shrinkage in composite materials, protective coatings for tooth and restoration surfaces and glass-ceramic tooth colored restorative materials,” said Drago Skrtic, Ph.D., director of research at the ADA Foundation Volpe Research Center. “He has brought the science of molecular modeling to dental adhesives and has made significant advances in the modeling of dental collagen for the purpose of elucidating the chemically functional groups that may more completely bind to dentin and enamel.”
As a young dentist in private practice in the early 1950s, Dr. Bowen was frustrated with poor-quality direct filling materials and began exploring potential options. He set up a laboratory on his back porch in San Diego, where he had moved after dental school.
“I tried to make a hybrid material using a commercial epoxy resin as an adhesive binder to glue together powdered particles of silica glass or dental porcelain,” Dr. Bowen told the ADA News in 1994.
With continued manipulation of these materials, he managed a breakthrough. “It occurred to me to replace the epoxy group on each end of this same kind of molecule with a methacrylate group,” he said. “It was known that methacrylate groups polymerize rapidly under oral conditions. I hoped that the rest of the molecule would contribute many of the good properties of epoxies that made them so useful in many industrial applications.” His efforts led to the creation of BIS-GMA resin, patented in 1962.
Dr. Bowen joined the ADA staff in 1956 after his first published research paper and presentation at an International Association for Dental Research meeting led to encountering Dr. Robert Nelson of the ADA Research Unit, which evolved to become first the ADA Paffenbarger Research Center and later the ADA Foundation Dr. Anthony Volpe Research Center. There, Dr. Bowen continued his work on composites.
After years of research achievement for the ADA, including development of many other dental materials, Dr. Bowen served as director of the Paffenbarger Research Center in 1983 until 1994. He traded his director duties to become the ADA’s first distinguished scientist in 1994, allowing him to focus again on full-time research.
In the recent years, as the VRC’s Distinguished Scientist, Dr. Bowen worked on design on new dental monomers capable of resisting hydrolytic and enzymatic degradation in harsh oral environment, Dr. Skrtic said.
For his contributions to dentistry he received numerous recognitions, including the ADA Distinguished Service Award in 1999 for his long career of innovative research contributions that have benefited the dental profession and general public.
“I have been fortunate to work with Dr. Bowen for over 10 years,” Dr. Sun said. “I was impressed by his achievement, his knowledge, and his rigor in research. His work inspired many scientists like me to pursue a research and development career in dentistry.”