Four 91̽��School of Dentistry faculty members have received a patent for a new way of using titanium-based materials to fight oral bacteria.

The patent culminates several years of work in which the group studied a novel class of substances called titanates and peroxotitanates, which can inhibit bacterial growth when bound to metal ions. These titanates could be incorporated into a gel or a solution that would be applied by a dentist after a procedure such as a root canal or a filling. The application could reduce the chances of infection or tooth decay at that site.

Titanates could also be used in bandages, skin gels, mouthwashes and toothpaste to limit bacterial growth, said Dr. Whasun Oh Chung, research associate professor of oral health science, who works on this new antibacterial agent. The others are Dr. Daniel Chan and Dr. John Wataha, both professors  of restorative dentistry; and Dr. Bruce Rutherford, lecturer in oral biology.

The group’s work grew out of nearly a decade of research performed by Wataha and Dr. David Hobbs of South Carolina’s Savannah River National Laboratory. Hobbs is also listed on the patent as an inventor.  Their studies formed the basis for a four-year, $1.5 million federal grant by the National Institute of Dental and Craniofacial Research to the 91̽��School of Dentistry to evaluate titanates’ antibacterial properties.

Chan, the School of Dentistry’s associate dean for clinical services, was co-principal investigator on the grant with Dr. James Bryers of the 91̽��Department of Biomedical Engineering.  Whasun Oh Chung and another School of Dentistry faculty member, Dr. Albert K.H. Chung, were co-investigators.  Dr. Charles Spiekerman of the School of Dentistry’s Department of Oral Health Sciences is the group’s biostatistician, while Wataha is  a consultant. Hobbs helped secure the grant.

Metals have long been known to have antibacterial properties, said Whasun Oh Chung, but, when used in concentrations high enough to be effective, they also carry a risk of toxic side effects. What makes the work with titanates promising, she said, is that the therapeutic benefits are achieved with less risk of toxicity.

“It is very new and novel,” said Chung. “Nothing has delivered materials at such a non-toxic level. We’re working with something we know is effective. Metals have been around a long time, and the bacteria haven’t become resistant to them.”

That is also an important consideration at a time when growing bacterial resistance to antibiotics places greater urgency on the need to find antimicrobial alternatives, she noted.

“The use of metal ions to control bacterial infections remains of interest as drug-resistant bacteria are becoming increasingly common and dangerous to human health,” Chung said.

Aside from their uses in the mouth or other topical applications, titanates could even be used in narrowly targeted treatments for internal organs, she said.

Titanates could also be used in dental or medical materials and devices, she said, including suture material, catheters, shunts, and dental fillings. They could even show up in toothpastes and mouthwashes some day, she said.

“[Titanate-metal complexes have] proven to be effective against endodontic, cariogenic  and periodontic bacteria,” Chung said. “The idea is to make it easy for people to use every day.” At the same time, Wataha cautioned that the practical or clinical benefits have yet to be conclusively demonstrated for the new patent-related application.

The researchers are now conducting human trials and expect to finish this spring, Chung said. However, she declined to predict when titanates might be approved for general use.

Twelve-year-old Samuel, who has cerebral palsy, is a huge soccer fan. As Yedlin entered the dental operatory room and said, “Hi, buddy,” Samuel broke into a huge smile that never dimmed.

“I knew him by his face,” Samuel said, accepting a handshake and an autographed framed photo and cap from Yedlin, a speedy right back for Seattle’s Major League Soccer team.

“When he first walked in, I’m like, ‘That looks like DeAndre.’ ”

After a brief conversation with Samuel about his soccer interests and Yedlin’s trademark game-day hair styles, and posing for photos, Yedlin said, “I’m glad I could do this for you. Glad you enjoyed this dentist appointment.”

The idea for the surprise visit, which took place just before Thanksgiving, was hatched by Samuel’s dentist, third-year 91̽��pediatric dental resident Jane Stieber, who enlisted the help of Linda Yedlin, administrator for the 91̽��Department of Pediatric Dentistry and DeAndre’s grandmother.

Last spring, Stieber visited Yedlin’s office and noted the many newspaper photos of DeAndre, who recently came third in voting for MLS Rookie of the Year and made the MLS all-star team this year. Yedlin explained her connection to the Sounders’ first home-grown player and Stieber thought it would be great to have DeAndre and Samuel meet.

“Samuel recently survived a roller-coaster orthodontic journey here at The Center with a great clinical outcome,” said Stieber, who has been treating Samuel for two years, back when he was in braces. “He lived in an orphanage in China until age 8 and has two adopted sisters from China with special needs who are treated by our dentists at Seattle Children’s.” The Center for Pediatric Dentistry is a partnership between the 91̽��and Seattle Children’s hospital. It has particular expertise in treating children with special needs, including a clinic for children with autism.

The initial appointments were tough for Samuel, who “wanted to rip his braces off,” said Stieber. When she found out Samuel loved soccer, she started reading up on the Sounders, hoping to earn his trust. Samuel became so comfortable with their conversations that he started correcting her “facts.”

The Knorr family – all of whom were in on the surprise for Samuel – includes parents Cheri and Gregg, and sisters Sarah, 9, and Hannah, 10. Brothers Joshua, also 12, and Andrew, 15. who are soccer players and Sounders fans in their own right, persuaded their mom to take them along to Samuel’s appointment.

Samuel has played in the TOPSoccer program, designed for children with disabilities. Now he plays FIFA video games daily.

“I’ve been working on this (surprise meeting) for months,” said Stieber. “It was perfect.”

Everyone agreed.

“I can’t believe it,” said Samuel as he left the exam room. “My teacher is a Sounders fan. I can tell her I finally met a Sounders player.”