Preventive dentistry has taken long strides in the direction of eliminating dental diseases. In this endeavour, the caries vaccine has generated a good deal of enthusiasm. This modality of treatment can prevent the occurrence of dental decay on a large scale.
The concept of a vaccine can be visualised primarily with the recognition of mutans streptococci as the key microorganisms in the development of decay. Thus efforts have been directed at preventing its colonization in the oral cavity.
How it works
The basis of a vaccine is that it keeps the patient in a state of readiness such that in case an infection does occur, an immune response which is more rapid and effective can be mounted. Thus, during the first response, memory cells are created, that later remember the earlier attack and respond much more effectively.
The significance of antibodies in the protection against dental decay, lies in the presence of high levels of anti-bodies in the fluid of gums, which have been correlated with low levels of decay.
Routes of administration
The various routes that have been tried out include:
- Oral Route: Considered safer than systemic route.
- Systemic route: This has been tried in monkeys.
- Active gingivo-salivary route: In order to limit the potential side effects, this has been tried in the gums of rabbit and monkeys.
- Active immunization
Various new approaches have been tried out in order to overcome the existing disadvantages.
Passive immunization involves passive or external supplementation of the antibodies. This carries the disadvantage of repeated applications as the immunity conferred is temporary.
Several approaches tried out are:
- Monoclonal antibodies: The topical application in human subjects brought a marked reduction in the implanted dominant microorganism.
- Bovine milk and whey: Systemic immunization of cows with a vaccine leads to the bovine milk and whey containing antibodies. The immune whey brought a reduction in the caries level in a rat model.
This whey was also used in a mouth rinse by Filler et al . This resulted in lower percentage of microbes of plaque.
- Egg-yolk antibodies: The novel concept of using hen egg-yolk antibodies against the microorganisms was introduced by Hamada .
- Transgenic plants: Large scale production is possible as it would be quite cheap.
An Apple a Day…
Researchers are working on ways to inject a protein fragment into fruit, which blocks the plaque dominant microbes, so that cavities and painful visits to the dentist could become a thing of the past.
British scientists at Guys Hospital in London have already isolated a gene and the protein fragment that prevents the bacteria from sticking to the teeth. Professor David James (2000), a plant biotechnologist at the Horticulture Research International in Southern England, is trying to find ways to deliver the protein into the mouth through apples and strawberries.
Though some difficulties are being faced at the present, caries vaccine is certainly a very vibrant issue. The potential implications are enormous and should be pursued with the same vigour as before.