Here are the 4 maxillary molars that I treated in my practice today. 3 are second molars and 1 first molar. All teeth had 4 canals. 3 of the teeth had mb1 join mb2. One had 2 separate canals. All the cases were done in 1 visit. All teeth had self cure resin cores placed in the same visit to prevent coronal leakage and prevent tooth loss.
Many patients , once they are out of discomfort , will delay the placement of crowns
leaving temporary fillings in endo treated teeth for more than a 2-4 weeks is not a good practice. My protocol is once the patient is anesthetised, apply rubber dam, remove decay, and any undermined tooth structure. Make my access into the chamber (if one exists) identify all canals, extend my coronal access into the canals to create straight line access to the canals. Use full strength bleach and 17% EDTA as irrigants. I use typically 20 ml of bleach for each canal and 5 ml of EDTA for each canal.
I typically use the irrigants between each file. I use NITI rotary instruments for bulk shaping of the canal and a lot of hand .02T hand instruments to fine tune the apical perparations. 
I use electronic Apex locator to determine the length of the canals. Of course, sometimes I take graphs/cone fit images to verify length and more so to rule out additional anatomy in the canals. So I like to call them working wire images than working length images.
Once the canals are fully shaped, I fit tapered cones usually .08T tapered cones. Once the canals are dried, I use paperponts to verify my length and then trim the cones to the final lengths. Warm vertical obturation is the choice of my obturation. I use Touch N Heat to do a down pack to at least 4-5 mm from the apex and then back fill with Obtura gun. Then clean off the chamber with alcohol, EDTA and then etch, bond and retore with self cure or dual cure resin and very often amalgam all under the rubber dam.
The whole procedure , once the rubber dam goes on, to it comes off, is done under a microscope. This allows the treatment to be done very precisely, find all the canals through the chamber calcifications, deep exploration of the canal spaces for deep splits, removing separated instruments, bypassing the ledges. The overall quality of the treatment improves significantly if the scope is used for the whole procedure. Quaity endodontics takes time, commitment and an attitide for excellence.
The results will speak for themselves when these criteria are met. No one does a perfect case every time, but consistency can be achieved if these principles are followed.
