Surgical treatment for severe endodontic-periodontal lesion: A case report with 2-year follow-up.

Background: Various surgical techniques have recently been developed for periodontal tissue regeneration, especially those do not involve any incisions in the interdental papillae at the regeneration site. These techniques have significant advantages for obtaining clinical attachment gain with least amount of gingival recession, however, may also have disadvantages such as limited field of surgical view, difficulty in debridement, and limited access only from the buccal side. This case report addresses a 2-year follow-up with a novel surgical approach to achieve periodontal regeneration that overcomes these limitations: the flexible tunnel technique (FTT).

Methods: In a 66-year-old patient, in an enclosing infrabony defect extending to the root apex on the palatal side, which appeared to be an endodontic-periodontal lesion on tooth #5, four vertical incisions and a periosteal releasing incision were performed in order to make the interdental papillae easier to translocate over the abutment teeth, which led to obtain clearer operative field. After debridement, the enamel matrix derivative was applied to the root surface and the infrabony defect was filled with deproteinized bovine bone mineral. The flaps were relocated, and simple interrupted sutures were performed.

Results: One year later, pocket closure and improvement of bone defects were observed without gingival recession. After confirmation with improved mobility, a full zirconia crown was placed. During 2-year follow-up, periodontal tissue was maintained well without any complication.

Conclusions: The FTT can be used to approach endodontic-periodontal lesions and infrabony defects extending to the root apex without incision of the interdental papillae.

Key points: A more accessible tunnel technique can be performed by using four vertical incisions. If the tooth is abutment, interdental papillae can be flexible to translocate due to this tunnel technique with vertical incisions. Ensuring root surface debridement, application of regenerative materials, and wound stability are the keys to this regenerative procedure. The patient needs to understand the risks associated with the proposed periodontal regenerative surgery and the prognosis of tooth.

Plain language summary: Various surgical techniques have been developed recently to help regenerate the tissues that support teeth, especially methods that avoid making cuts in the gum tissue between the teeth at the treatment site. However, these techniques may have some drawbacks, such as limited visibility during surgery, difficulty cleaning the area, and access only from the outer side of the teeth. This case report addresses a 2-year follow-up of a new surgical method aimed at overcoming these challenges: the flexible tunnel technique (FTT). In a deep bone defect extending to the tip of the tooth root on the roof side, four vertical cuts and a cut to stretch the gum were made to allow better access. After cleaning the area, an enamel matrix derivative was applied to the root surface and filled with deproteinized bovine bone mineral. The area was then closed with simple stitches. After 2 years, the pocket was closed, and the bone defect improved. The FTT may be a useful technique for restoring the support structures around teeth in deep bone defects extending to the root tip without cutting the gum tissue between the teeth.