Based on symptoms. The treatment is based on your symptoms and the result of tests done by your dentist. If the tooth is somewhat cold sensitive, then it may not need root canal. If pain lingers, after cold stimuli, and throbs, and/ or is sensitive to heat, then a root canal is probably needed.
Depends. Pulpitis can be reversible or irreversible. Reversible pulpitis can often be treated with a sedative filling, followed by a permanent filling. Occasionally just removal of the cause of pulpitis is enough for symptoms to resolve. Irreversible pulpitis requires root canal treatment or extraction.
RCT or extraction. Root canal or extraction.
Depends on whether. It is reversible or irreversible pulpitis. The former can often be relieved with an occlusal adjustment / palliative treatment. The latter required endodontic therapy (root canal therapy).
Depends. Pulpitis means inflammation of the tooth pulp (nerve) causing tooth to hurt. It can be reversible or irreversible. Reversible pulpitis can be eliminated by removing the cause. Adjusting a new filling/crown that is too high or wearing a night guard to prevent grinding will stop pulpitis. Irreversible pulpitis is when the pulp is too sick to heal itself and a root canal or extraction is required.