Organisms involved in pit and fissure caries:: (A) Streptococcus mutans., (B) Lactobacillus., (C) Actinomyces., (D) All of the above.
Answer is D. Pit & fissure caries in initiated by a wide variety of organisms like S. mutans, Lactobacillus and Actinomyces species as they colonize in these retentive areas. However, only S.mutans (very significantly) & S. salivarius (by chance) have been proved to colonise smooth surfaces.