https://aap.onlinelibrary.wiley.com/doi/abs/10.1002/JPER.20-0288
Aslan S, Buduneli N, Cortellini P. 2020.  J Periodontol. doi: 10.1002/JPER.20-0288.

Aim:
Evaluation of the clinical applicability of the entire papilla preservation (EPP) technique in the regenerative treatment of isolated deep intrabony defects using collprotect® membrane and cerabone®.

Material/Methods:
Fifteen healthy, non-smoker patients with one isolated deep intrabony defect each (baseline probing depth (PD): 9.03±1.62 mm; clinical attachment level (CAL): 11.16±1.81 mm) were treated with guided tissue regeneration. Surgical access to the defect occured by a single buccal vertical incision with an interdental tunnelling flap. Following removal of granulation tissue, the intrabony defect was filled with cerabone®. The collprotect® membrane was trimmed and placed under the intact defect-associated papilla with palatal positioning suture. Microsurgical sutures were used for primary closure.

Results/ Conclusion:
All 15 sites presented uneventful healing at 1 week post-op. Any adverse effects, such as haematoma, pain, discomfort, oedema, and additional painkiller intake were recorded. During the study period, all sites showed 100% primary closure without membrane exposure in the early wound healing phase. At 1-year follow-up, an average CAL gain of 5.86±1.28 mm, PD reduction of 6.1±1.47 mm, and minimal increase in gingival recession of 0.23±0.62 mm were observed.
This novel surgical technique, that keeps the interdental papilla intact, seems promising to provide optimal biomaterial protection and healing conditions, even when a collagen barrier and bone substitutes are applied.