Which bacteria is primarily responsible for tooth decay?

The bacteria primarily responsible for tooth decay is Mutans streptococci. This group of bacteria, particularly Streptococcus mutans, plays a crucial role in the development of dental caries (tooth decay) due to their ability to metabolize sugars and produce acid as a byproduct. The acid produced by these bacteria can demineralize the enamel, leading to cavities over time.

Streptococcus mutans is commonly found in the oral cavity and thrives in environments with high sugar concentrations. Its adhesive properties also allow it to form biofilms, particularly in dental plaque, which contributes to the progression of tooth decay. Understanding the role of these bacteria is essential for developing effective preventive measures against caries.

Other bacteria mentioned, such as Lactobacillus casei, while involved in the caries process, do not initiate decay as effectively as Mutans streptococci. Staphylococcus aureus is more associated with infections outside of dental health, and Porphyromonas gingivalis is primarily linked to periodontal disease rather than tooth decay. Thus, the significance of Mutans streptococci in tooth decay is well documented in dental research and education.