The second most common reason for extraction of root filled teeth is periodontal disease. So it’s important we identify periodontal disease when deciding if we should treat a tooth. Periodontal pockets around teeth can generally be due to three things:
1. Periodontal disease;
2. Vertical root fracture;
3. A sinus tract draining through the PDL.
Usually, a true periodontal pocket will be broad, whereas a pocket due to a root fracture or a draining sinus will be very narrow. We are more likely to find a true periodontal pocket in a patient who suffers periodontal disease in other teeth besides the one we are looking at.
When we do identify a periodontal pocket in a tooth that also has apical periodontitis, we want to know if the periodontal disease is separate to the apical disease. When these two are combined in a perio/endo lesion, the success rate in treating the teeth is lower than when we have separate perio and endo disease. If the pocket is narrow, then it’s important to differentiate between the draining sinus (which may be easy to treat) and the root fracture, which cannot be treated. I usually do this by raising a flap and inspecting the root with the microscope after staining with methylene blue.
In cases where I find a very deep, broad periodontal pocket which I think may be to the apex of the tooth, I place a GP point in the pocket to full length and take a radiograph. If the GP extends to the apex, then I know we have a fight on our hands to save the tooth.
In the comments section, please leave your tips on identifying perio/endo lesions.