Final answer:
Caries are caused by acid-producing bacteria such as Streptococcus mutans, Lactobacillus, Leuconostoc, and Actinomyces species that ferment sugars in the mouth. Streptococcus mutans is the most significant cariogenic species. Regular oral hygiene can prevent the overgrowth of these bacteria and the formation of plaque.
Step-by-step explanation:
The acid-producing bacteria that cause caries include a variety of species, with Streptococcus mutans being the most significant. These bacteria metabolize sugars from food, such as sucrose, into glucose and fructose. Glucose is used to strengthen the biofilm structure, while fructose undergoes fermentation to produce acids like lactic acid. These acids, over time, demineralize the tooth enamel and dentin, leading to caries.
Additionally, other bacteria such as Lactobacillus, Leuconostoc, and Actinomyces species are also involved in the production of acid through lactic acid fermentation. Regular oral hygiene and dental care can prevent dental caries by limiting the growth of these bacteria and removing plaque before it hardens into tartar.