FUTURE OFDENTISTRYu Assessment of fluoride exposure.
uInformation management systems to store and
evaluate data on the bacterial challenge, salivary status,
fluoride exposure, history of caries, and other risk fac-
tors, as a basis for planning a rational treatment proto-
col for the individual patient.
uIdentification of specific genes or genetic markers
that are associated with increased risk for severe,
extensive caries.
Dental Caries Prevention and Management
New and improved dental products and antibac-
terial agents are on the horizon. Products that more
effectively deliver fluoride and that provide antibacter-
ial action at the same time will prevent dental caries:
u The wider use of sealants in combination with
other preventive measures will occur.
u Chlorhexidine is currently the only antibacterial
agent that effectively kills mutans streptococci.
Lactobacilli are resistant to chlorhexidine; thus,
other treatments will be necessary to reduce or
eliminate them.
u Slow-release fluoride products are also likely to
become widely utilized.
u Antibacterial agents attached to antibodies that
react with the surfaces of cariogenic bacteria will
likely be developed.
u Products will be developed to supplement saliva's
function and protective components.
u Plant-derived genetically engineered antibodies
such as sIgA are currently under development as
a tool for inhibiting colonization of specific car-
iogenic bacteria.
Products incorporating specifically targeted anti-
bacterial agents will become available for use in the
dental office and most likely by prescription in the
home environment. Such products could also be
utilized in targeted community programs for reduc-
ing dental caries in populations and for blocking the
transfer of infection from the caregiver to the child.
Both positive and negative interactions occur
between different species of bacteria inhabiting the
same ecosystem. This provides the basis for a novel
approach to preventing microbial diseases called
"replacement therapy." In this approach, a harm-
less effector strain is permanently implanted in the
host's microflora. Once established, the presence of
the effector strain prevents the colonization or out-
growth of a particular pathogen.
To prevent dental caries in the future, replace-
ment therapy will involve construction of an effec-
tor strain derived from a clinical S. mutansisolate.
Recombinant DNA technology will be used to
delete the gene encoding lactate dehydrogensome
making it entirely deficit in lactic acid production
(Hillman et al, 2000). Because of its strong colo-
nization properties, a single application of the effec-
tor strain to patients should result in its permanent
implantation and development of indigenous, dis-
ease-causing S. mutansstrains over time. Thus,
replacement therapy for the prevention of dental
caries is an example of biofilm engineering that
offers the potential for a highly efficient, cost-effec-
tive augmentation of conventional preventive strate-
gies. Attendant concerns are the compatibility of the
engineered organism with the normal flora, the abil-
ity of the organism to successfully colonize the oral
cavity, and the regulatory issues related to safety of
the new organism (Mandell, 1996).
There has been considerable interest in the devel-
opment of a caries vaccine (Smith and Taubman,
1997; and Russell et al, 1999). These studies have
considered the importance of humoral immunity in
the caries process. Concerns have been raised about
the safety of newly introduced vaccines and the rel-
ative effectiveness compared to other preventive
approaches. Vaccines based on systemic inoculation
are unlikely to be approved. Rather, approaches
that may be more practical are based on mucosal
immunization and production of salivary IgA anti-
body to mutans streptococci and passive immuniza-
tion. Furthermore, the use of such a vaccine would
likely be limited to high-risk individuals, i.e. patients
with persistent xerostomia (Mandell, 1996).
Laboratory studies have shown that specific laser irra-
diation can alter the surface mineral of the enamel and
make it highly resistant to subsequent acid dissolution
(Featherstone et al, 1998). Consequently, carbon diox-
ide lasers with specific laser characteristics designed for
this purpose, and potentially Er:YAG and Er:YSSG
lasers, could be used to treat specific areas in caries-sus-
ceptible individuals to inhibit caries progression. Ideally,Dental and Craniofacial Research