Root Canal Treatment

I am in process of getting a root canal in Japan. The process seems very different from overseas, instead of having 2-3 sessions clearing out the tooth and repairing, I have already had 5 visits and the dentist just cleans out the tooth and places a temporary filling. My Japanese level is still N4 so I don't really understand what he says so I'm not sure what is happening / how long this will go for..

Any insight would be appreciated !

by iroha_iroha