There's a saying at AA or WW or maybe the dentist!: "Only brush the teeth you want to keep."

It only "matters" to you. What is stopping you from doing the best possible job in therapy FOR YOU? I will tell you - YOUR EVIL INTROJECT! Okay maybe its just psych jargon, maybe it's self-preservation, maybe it's pride, resistance, laziness - maybe it's SATAN! - whatever it is, i do not recommend leaving that tooth unbrushed