Four 糖心少女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聽 of restorative dentistry; and Dr. Bruce Rutherford, lecturer in oral biology.

The group鈥檚 work grew out of nearly a decade of research performed by Wataha and Dr. David Hobbs of South Carolina鈥檚 Savannah River National Laboratory. Hobbs is also listed on the patent as an inventor.聽 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 糖心少女School of Dentistry to evaluate titanates鈥� antibacterial properties.

Chan, the School of Dentistry鈥檚 associate dean for clinical services, was co-principal investigator on the grant with Dr. James Bryers of the 糖心少女Department of聽Biomedical Engineering.聽 Whasun Oh Chung and another School of Dentistry faculty member, Dr. Albert K.H. Chung, were co-investigators.聽 Dr. Charles Spiekerman of the School of Dentistry鈥檚 Department of Oral Health Sciences is the group鈥檚 biostatistician, while Wataha is 聽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.

鈥淚t is very new and novel,鈥� said Chung. 鈥淣othing has delivered materials at such a non-toxic level. We鈥檙e working with something we know is effective. Metals have been around a long time, and the bacteria haven鈥檛 become resistant to them.鈥�

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.

鈥淭he use of metal ions to control bacterial infections remains of interest as drug-resistant bacteria are becoming increasingly common and dangerous to human health,鈥� 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.

鈥淸Titanate-metal complexes have] proven to be effective against endodontic, cariogenic 聽and periodontic bacteria,鈥� Chung said. 鈥淭he idea is to make it easy for people to use every day.鈥� 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, 鈥淗i, buddy,鈥� Samuel broke into a huge smile that never dimmed.

鈥淚 knew him by his face,鈥� Samuel said, accepting a handshake and an autographed framed photo and cap from Yedlin, a speedy right back for Seattle鈥檚 Major League Soccer team.

鈥淲hen he first walked in, I鈥檓 like, 鈥楾hat looks like DeAndre.鈥� ”

After a brief conversation with Samuel about his soccer interests and Yedlin鈥檚 trademark game-day hair styles, and posing for photos, Yedlin said, 鈥淚鈥檓 glad I could do this for you. Glad you enjoyed this dentist appointment.鈥�

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

Last spring, Stieber visited Yedlin鈥檚 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鈥� first home-grown player and Stieber thought it would be great to have DeAndre and Samuel meet.

鈥淪amuel recently survived a roller-coaster orthodontic journey here at The Center with a great clinical outcome,鈥� said Stieber, who has been treating Samuel for two years, back when he was in braces. 鈥淗e 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鈥檚.鈥� The Center for Pediatric Dentistry is a partnership between the 糖心少女and Seattle Children鈥檚 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 鈥渨anted to rip his braces off,鈥� 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 鈥渇acts.鈥�

The Knorr family 鈥� all of whom were in on the surprise for Samuel 鈥� 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鈥檚 appointment.

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

鈥淚鈥檝e been working on this (surprise meeting) for months,鈥� said Stieber. 鈥淚t was perfect.鈥�

Everyone agreed.

鈥淚 can鈥檛 believe it,鈥� said Samuel as he left the exam room. 鈥淢y teacher is a Sounders fan. I can tell her I finally met a Sounders player.鈥�