Just because dental caries show up with plaque and tartar in no way means that plaque and tartar are causing the caries. These are the mechanism our body uses to protect our teeth from unbalanced oral bacteria. Just like the microbiome of the gut, we have one in our mouth. Removing plaque and tartar does not stop caries.

Caries are initiated by direct demineralization of the enamel of teeth due to lactic acid and other organic acids which accumulate in dental plaque. What is tartar?

Heavy staining and calculus deposits exhibited on the lingual surface of the mandibular anterior teeth, along the gumline

Tartar is a form of hardened dental plaque. It is caused by precipitation of minerals from saliva and gingival crevicular fluid in plaque on the teeth. This process of precipitation kills the bacterial cells within dental plaque.