Optimizing papillary incision design in molar periodontal regenerative therapy: A case study.

[BACKGROUND] While the simplified papilla preservation flap is commonly recommended in the molar region, it may not be optimal when blood flow and microsurgical visibility are considered. This case study aimed to evaluate the relationship between surgical visibility and interdental incision designs in the molar region and to propose a decision-making framework for interdental papilla incision design based on the extent of flap elevation and blood supply.

[METHODS] Three cases of periodontal regenerative therapy in the molar regions were performed using different flap designs: extended flap with circumferential defect (3 mm depth) and minimally invasive surgical technique (MIST) and modified MIST (M-MIST) with combination defects (4 mm depth), both incorporating interdental incision designs with a buccal or palatal shift. Clinical parameters and radiographic outcomes were assessed at baseline and 6 months postoperatively.

[RESULTS] The initial probing pocket depths of 10, 9, and 8 mm were reduced to 4, 4, and 3 mm, respectively, with radiographic evidence of bone-filling in all cases. Cases using MIST and M-MIST demonstrated superior primary healing compared with the extended flap case. Interdental incision designs with a buccal or palatal shift improved visibility and operability during microsurgery in molar regions.

[CONCLUSIONS] This case study showed that buccal- or palatal-shifted interdental incision designs were effective for molar periodontal regenerative therapy under operating microscopes. The decision-making process for interdental incision designs should consider the inter-root distance as well as the extent of flap elevation and its impact on blood supply.

[KEY POINTS] Buccal- or palatal-shifted interdental incision designs using an appropriate flap design can be successfully applied to molar regions. Microscope-enhanced visibility with buccal- or palatal-shifted interdental incision designs improves surgical precision and accessibility. Preservation of the blood supply is crucial for optimal wound healing.

[PLAIN LANGUAGE SUMMARY] Successful periodontal regenerative therapy in molar regions requires adequate surgical access and preservation of the interdental papilla. Although various minimally invasive techniques are available, accessing deep bone defects in molar regions while maintaining blood supply to the papilla remains challenging. In this context, interdental papilla incision designs that shift the incision line to the buccal or palatal aspect-such as the papilla preservation technique, modified papilla preservation technique, and triangle papilla access approach-are considered to contribute to improved visibility in periodontal regenerative therapy in the molar region using the operating microscope (OM). Building on this, the present case study proposes a new decision-making framework for interdental papilla incision design, with an emphasis on enhancing visibility under the OM and considering the anatomical relationship between flap design and blood supply.