Joby Peter1, S. Rupesh2, G. Mohan3, D. K. Sugumaran4, S. Thayumanavan5, N. Venugopal Reddy6, Arun Prassad Rao7, R. Krishnnakumar8
INTRODUCTION:
ROLE OF GENETICS IN CARIES PREVENTION: The use of genetic engineering to prevent caries has led to the down of a new era in caries prevention. Once successfully tested on human models, use of such modalities as genetic manipulation, genetic modification or recombinant technology may have the potential to revolutionize the whole mode of caries prevention. The various approaches that have been taken in this direction are (Fig. 1):-Altering the cariogenic flora:
1. Genetically modified foods.
2. Gene alterations.
ALTERING THE CARIOGENIC FLORA: Microorganisms play a vital role in the causation of dental caries. Among them s. mutans (a spherical bacterium) that thrives on the organic film that coats the tooth surfaces and produces the enzyme lactate dehydrogenase, plays the lead role.
In rat experiments, scientists found that a type of bacteria called lactobacilluszeas, could be genetically modified to produce antibodies to attach the themselves to the surface of s.mutans. Such bacteria are known as ‘Genetically modified good Bacteria’. The antibodies produced by them grab the free floating s. mutans in saliva and give them a „Kiss of death???.
Hillman [2002] used recombinant DNA technology to create a strain of s. mutans [BCS3-L1] that lacks the lactate dehydrogenase gene. This harmless effector strain is permanently implanted in the host that kills conventional caries producing s.mutans without harming other bacteria. The BCS3-L1 replacement therapy for the prevention of dental caries is an example of biofilm engineering that offers the potential for highly efficient, cost effective augmentations of conventional prevention strategies.
Dr. Lawrence of the National Institute of Dental and craniofacial research prefers the concept of replacing s.mutans with a species engineered to rebuild both surface. Another approach that has been tried is the use of a strain of s.mutans engineered to increase the production of urease, which converts urea to ammonia to create conditions conductive to enamel re mineralization.
