CARIES VACCINE – WHY IT’S FAILED?

DEFINITION

• •     CARIES VACCINE-

Vaccine is an immunobiological substance designed to produce specific protection against a given disease.

WHY VACCINATION AGAINST DENTAL CARIES?

1. Transmissible & infectious nature of dental caries. 2)Discovery & Understanding of immune system.

IMMUNITY

1. Resistance offered by host against any pathogenic microbes.
   1. Natural resistance by the body can be increased by immunization. TYPES OF IMMUNITY
      1. NATURAL.
      1. ACQUIRED.
         1. ACTIVE

1. Natural 2.Artificial
   1. PASSIVE

TYPES OF CARIES VACCINES

Vaccines may be prepared from:

• Live modified organism.
  • Inactivated or killed organism.
  • Extracted cellular fraction, toxoid or combination.
  • Most commonly used vaccine was prepared from heat killed or formalin treated S.mutans. But it induced Heart Cross Reactive Antigens(HCRA) that could damage the heart.

• Repeated s.c.injection of formalin killed S.mutans in freunds

adjuvant were administered adjacent to salivary glands along with installation of S.mutans into parotid gland.

• Resulted  in  formation  of  both  salivary  IgA and  serum  IgG

antibodies.

• Inoculation with similar antigen in site remote from salivary gland were less successful.

PARENTERAL IMMUNIZATION:

• Killed S.mutans were administered to free rats in drinking water for 45 days.
  • Result: Significant reduction in caries
  • Inference:
• Increased level of salivary IgA antibodies to S.mutans [acquired by passive transfer through milk of lactating rats to

their litter]

• IgG antibodies were absorbed by GIT tract of offspring to

enter blood.

• Passive transfer of IgA: direct protection by preventing adherence

of S.mutans to tooth.

• Absorbed IgG: indirect protection affecting tooth via crevicular fluid saliva.

ORAL SUB MUCOUS IMMUNIZATION:

• Cells or cell wall + adjuvant injected under mucosa of buccal sulci of 4 quadrants of mouth.
  • Result: significant reduction in caries(similar to s.c.immunization).
  • Untried route which might lead to some discomfort and possibly complications it has not been pursued energetically.

• People who moderately effected by S.mutans may swallow several

millions of these microorganisms per day without any effect. Reactive with homologous micro organism

CONCLUSION

As per latest evidences researches are happening plenty in the field of caries vaccine. but as caries belong to multifactorial causation pathology vaccine cannot contain all the factors of causation but agent factor /microflora. The host/environmental factors cant be controlled or modified by vaccine hence formation of dental caries. Hence vaccines are not a remedy or a solution for dental caries prevention rather it can be done through proper brushing and regular dental check ups.