How do I choose the best Root Canal Specialist in London?

I've been dealing with persistent tooth pain for the past few weeks, and my general dentist has recommended that I visit a Root Canal Specialist London for further evaluation. Since this is my first time seeing a specialist, I'm unsure what factors I should consider before booking an appointment. Should I look for additional qualifications, years of experience, patient reviews, or advanced technology like CBCT scans and dental microscopes? Does choosing a specialist improve the chances of saving the tooth compared to a general dentist? I would appreciate any advice, personal experiences, or recommendations from people who have undergone root canal treatment in London.