Collaborations with Dr. Sheng Zhang
- Dr. Jimmy Chan
- Apr 4
- 4 min read
Updated: Apr 5
While in Auckland, I was fortunate enough to work with my good friend, Dr. Sheng Zhang, from Dental Artistry. We performed many joint surgeries together to manage a plethora of complex endodontic and periodontic problems.
In this blog, we will explain one of these joint cases.
A patient presented with a painful tooth (46) and persisting thermal sensitivity that did not resolve after initiation of root canal treatment. Upon further investigation, there was an undiagnosed grade 2 furcation defect due to an enamel projection towards the furcation and a missed radix canal.
After explaining to the patient that endodontic treatment alone will not resolve his issues and the pain that the he was experiencing was due to the accumulation of debris at furcation site.
The treatment plan offered to him was to complete his endodontic treatment by me and Dr. Zhang to perform guided tissue regeneration at the furcation. He accepted the treatment plan.
The radix canals are often missed and are difficult to negotiate. The trick is to use the buccal pit as the reference point and use small size K files like 6, 8 and 10 only. The canals were then prepared to a size 25 4%. The canals were then disinfected and medicated with calcium hydroxide.
He was reviewed a month later and he reported that the pain still comes and goes but his thermal sensitivity has resolved. His tooth was not tender to percussion and associated periapical tissues are not tender to palpation. Furthermore, there is no development of a periapical radiolucency on the follow up radiograph. Thus, I am confident that my root canal treatment was successful despite the persisting pain. (Root canal treatment can only control the contents of root canal spaces). His root canal treatment was thus completed and referred on to Dr. Zhang for the GTR.
From the basic sciences, periodontal tissues will not attach to enamel, thus forming a platform for biofilm to grow and eventually cause bone loss around the enamel projection. This will then allow material to accumulate inside the furcation causing inflammation and pain (His persistent pain problem). The enamel projection was then removed with a diamond tip ultrasonic and smoothen with hand instruments.
After the enamel projection has been removed, a connective tissue graft was harvested from the palate to be used as a "membrane". The reason being the seal around the furcation is crucial in GBR procedures as we do not want the bone graft material placed inside the furcation to be infected after flap closure. The CT graft acts as a living membrane that can protect the influx of saliva and bacteria.
Upon completion of filling the space with bone graft, the harvested CT graft was then placed over to cover the bone graft-Emdogain mixture acting as a biological barrier.
Once the graft is attached firmly, a muscle release was performed to to reapproximate the flap.
After 1 week, the appearance is concerning. However, if we think about it scientifically, what is going on, it is actually predictable. The CT graft was harvested from the palate, they will revascularize to the surrounding tissues, the graft is doing its job to protect the furcation.
The flap that was placed above(CT graft) allows the connective tissue to merge with the CT graft. THe old keratinised tissue will shed and new keratinisesd gingiva will form. Thus, we expect that after some more time the of keratinized tissue to emerge over the old attached gingiva.
After 1 month the tissue appearance improved no secondary infection of the graft. And the junctional epithelium starts to form at the furcation. Thus the advise is to not probe the area for at least 6 months. After six months....
His pain and swelling around the area is gone. He is satisfied with the results.
The crown was done by another favorite dentist of mine in Auckland, Dr. Sara Stockham. I cannot emphasis enough that a well sealing crown is as important as the root canal itself. GP is a terrible material to be placed inside root canal spaces. But this is the standard we all agree is good. Thank you SARA for the beautiful crowns and protecting my work always.
Successful treatment often times requires collaboration with other clinicians. I am grateful to have friends like Sheng and Sara who make me a better operator.