Root canal on 2nd pre-molar right before first molar, would a rubber dam be necessary?

Root canal.: In the United States, any root canal surgery or procedure of any kind requires to this day a rubber dam to be in compliance with the "standard of care". This is more of a court room decision then a patient care decision. In any lawsuit involving a root canal treated tooth, the first question the prosecuting attorney will ask is "did you use a rubber dam?" if no, then the case goes no further.

YES: Standard of care not withstanding, it simply makes sense. You need protection from the instruments possibly landing in your mouth/throat should there be a problem, and protection from the chemistry used to debride and cleanse the canal. The tooth needs to be protected from the bacterial saliva to ensure optimum results. Also, isolation for maximum vision critical.

Necessary & required: To perform root canal therapy without a rubber dam is to render care that falls below the standard of care.