by Sheila Smith Noonan
In dental research, there's triumph in finding a key part of the puzzle, but more often, greater knowledge from eliminating those pieces that don't fit. With a ranking of 16th in research funding among dental schools and new state-of-the-art laboratory facilities at the Dental Research Center (DRC), NJDS researchers are working to put the pieces together.
There are about 40-50 research projects at the school, with subjects ranging from juvenile periodontitis to tissue engineering, according to Dr. E. Dianne Rekow, acting associate dean for Research, Industrial Relations and Professional Development. Aside from their scientific and clinical implications, these studies are having other impacts at NJDS. "As soon as someone becomes involved with research, they never read scientific literature quite the same again," she says. "I've seen a tremendous impact on clinical faculty in how they evaluate new materials. Students who become involved in research projects, such as for the Balbo Expo, may find themselves following a different career path than they had previously envisioned."
Research at NJDS is drawing national attention, both within the dental community and from a corporate perspective. Significantly, there has been an increased collaborative research effort with other institutions. A prime example, says Dr. Rekow, is NJDS's proposed Craniofacial Repair Center of Discovery. This project would involve Princeton University, Rutgers University, and the New Jersey Institute of Technology on basic science, and such institutions as the University of North Carolina and the University of Puerto Rico on behavioral and clinical aspects.
NJDS continues to attract renowned researchers, such as Dr. Van Thompson, co-developer of the Maryland Bridge. He is one of eight researchers at the school who have both a dental degree and a doctor of philosophy. "As dentists, they bring an additional depth of understanding on the clinical impacts of their research," says Dr. Rekow.
The school is home to the DRC, a modern, state-of-the-art basic science research facility equipped for structure/function analysis of lipids, proteins, and nucleic acids. Among the Center's renowned scientists is its first director, Dr. Bronislaw Slomiany, professor of Oral Pathology, Biology and Diagnostic Sciences (OPBDS) as well as Biochemistry and Molecular Biology. His research focuses on analysis of lipids in saliva and mucus secretions and how these lipid-containing secretions relate to oral mucosal diseases. Dr. Amalia Slomiany, professor of Biochemistry and Molecular Biology; Medicine; and OPBDS, has been funded by the NIAAA for the past 16 years. Her studies concentrate on alcohol effects on the glycobiology of mucus secretions. A third scientist, Dr. Chinnaswamy Kasinathan, associate professor of OPBDS, emphasizes tyrosulfated proteins in glandular secretions. His work also is funded by the NIAAA.
Over the past two years, the Center has broadened its focus to include infectious diseases of the oral cavity. The new emphasis enables the DRC to be part of a university-wide focus on infectious disease, explains Dr. Daniel Fine, the Center's recently appointed director. This includes being part of the New Jersey Medical School's Emerging Pathogens group and interaction with its microbiology department. "There's been a rekindling of interest in infectious disease in the medical community, stemming both from the emergence of AIDS and increasing awareness that bacteria are becoming resistant to antibiotics," says Dr. Fine, professor of OPBDS. "Since dental researchers and NJDS have been involved with the study of infectious disease for many years, it was natural for us to participate in university-wide efforts."
Accordingly, juvenile periodontitis is the subject of two studies at the DRC. "From a scientist's viewpoint, juvenileperiodontitis provides an attractive model of infections related to periodontal disease," says Dr. Fine. "It is a relatively rare disease, occurring in about .5 percent of all juveniles ages 12 to 18, but in about 2 percent of African Americans, especially females. The disease is associated with a specific microorganism, Actinobacillus actinomycetemcomitans (Aa), and there appears to be an altered host response to this microbe."
One team of researchers, led by Dr. Fine, is seeking to understand how Aa attaches to teeth; what factors the microorganism contains that enable it to destroy bone and connective tissue; and how it avoids the host defense system and proliferates in the juvenile population.
Dr. Mark Wilson, an internationally known researcher who has recently come to NJDS, has made seminal discoveries about the host response to juvenile periodontitis: Immunoglobulins appear to be excessively produced in this population, particularly among African Americans, and the host defense cells that interact with these bacteria seem to have receptors that do not provide the kind of interaction that would satisfactorily remove the bacteria. "These kids have less cavities, but more periodontal disease, so there seems to be something that is encouraging the growth of Aa. The host may not be clearing the organism as efficiently as it might," says Dr. Fine. "The organism appears to be overtaking the ecological niche in the mouth and favoring the production of periodontal disease, while stymieing caries." Dr. Wilson, professor of OPBDS, also is developing a salivary screening test to identify populations that may be vulnerable to juvenile periodontitis.
Another study at the Center, led by Dr. Narayanan Ramasubbu, an x-ray crystallographer, is examining the functional and structural domains of amylase, an enzyme that interacts with Streptococcus mutans. The hope is to understand how amylase could be modified or how amylase can modify other carbohydrates and proteins that either enhance or reduce the adherence of S. mutans to the enamel surface.
The Center's research is conducted in a new, 6,000-square-foot laboratory that includes a Silicon Graphics computer for image analysis and molecular modeling; an isotope room; a darkroom; and facilities for nucleic acidanalysis. The new lab has been widely admired by corporate researchers visiting the facility.
The new lab, dedicated staff, and intriguing projects all bring momentum to research at NJDS, which fortifies the school as a whole. "Service, scholarship, and education are all key elements to a dental school," observes Dr. Rekow, "and ideally there's a balance between them. Our research program, which has been strengthened substantially, contributes to that balance."