Final answer:
The Excavator is the tool used to remove coronal pulp tissue and decay from a tooth. Microbes such as Streptococcus mutans contribute to tooth decay by metabolizing sugars and producing acids that erode dental enamel.
Step-by-step explanation:
The instrument used to remove coronal pulp tissue and decay from a tooth is the Excavator. This dental tool is specifically designed for the task of clearing out the soft decay and affected pulp from within the tooth's structure. When caries develop, treatment such as drilling to remove the decayed areas and filling them is fundamental to prevent deterioration. However, when the pulp is involved, the process often escalates to a root canal procedure, where it becomes essential to eliminate the infected tissues completely to prevent the spread of the infection and avoid painful complications like abscesses.
Microbes, especially bacteria, are the main culprits in contributing to tooth decay. The most significant cariogenic species of bacteria responsible for this is Streptococcus mutans. These bacteria thrive on sugars in the foods we eat and release acids that erode the dental enamel, leading to cavities.