Step 2 – Access Opening
Please see the diagram at the end of the section as a guideline for access openings. It is also important to check the angulation of your bur from different views to ensure that you are remaining within the outline of the tooth and have determined the proper long axis. REMEMBER to draw the long axis on the tooth you are going to access with a U-Mark pen. You can also look at the bitewing and estimate the level at which your bur should enter the pulp chamber.
There are 3 cardinal steps to access openings:
1. Outline deep in dentin to assess orientation and center the access.
2. Expose the pulp (the largest canal on multi-rooted teeth)
3. Unroof and refine
Begin accessing your tooth by using an endo access bur or diamond bur. Keep in mind your ideal access form mimics the occlusal surface and is always centered. Establish a straight-line access to all canals. If the access was done at a previous appointment, remove all the temporary material to prevent accidental blockage of canals during the procedure.
Clinic Tip: Do not be alarmed if you see some heme…this is normal, especially if the tooth is still somewhat vital.
Step 3 – Refine Access Opening
Do any refinement and final unroofing of the chamber with a tapered diamond or your Endo Z bur. Remember to use only circumferential prepping or a pull stroke when doing this to prevent gouging or a perforation. Locate your canals and be sure you have easy visibility of all canal orifices. Do not hunt for canals and destroy critical dentin structure. Faculty will always help you locate canals when you are at the proper depth.