Double-sided Entire Papilla Preservation (DEPP) technique was designed to allow access into a bone defect without compromising the integrity of papilla, when the defect extends to palatal/lingual side. This case-series study aimed to evaluate the clinical and radiographic outcomes of periodontal regenerative therapy using DEPP technique for intrabony defects. DEPP was performed with two vertical incisions on both the buccal and palatal sites to access the bone defect. After debridement, recombinant human fibroblast growth factor 2 or enamel matrix derivatives were used in combination with carbonate apatite (CO3Ap) or deproteinized bovine bone mineral (DBBM) to treat the defect. Periodontal parameters were evaluated at baseline, 6, and 12 months postoperatively. Values for clinical attachment level (CAL) and probing depth (PD) were statistically significantly improved compared with baseline at 6 months (P < 0.05) and 12 months (P < 0.01) following surgery. At 12 months, the mean PD reduction was 5.0 ± 1.4 mm and CAL gain was 5.3 ± 1.8 mm. According to the Composite Outcome Measure, the outcomes of the treated sites were considered ‘successful’. This case series demonstrates that DEPP can be effectively combined with regenerative therapy for intrabony defects, yielding favorable clinical outcomes with minimal surgical complications.