The present case series aimed to explore the potential clinical benefits of the application of dental pulp stem cells (DPSCs) in the regenerative treatment of deep intrabony defects. A total of 11 isolated intrabony defects in 11 chronic periodontitis patients were accessed with a minimally invasive flap and filled with DPSCs loaded on a collagen sponge. A tooth requiring extraction for impaction or malpositioning was used as an autologous source for DPSCs. An average clinical attachment level gain of 4.7 ± 1.5 mm associated with a residual mean probing depth (PD) of 3.2 ± 0.9 mm and remarkable stability of the gingival margin was observed at 1 year. Complete pocket closure (PD ≤ 3 mm) was achieved in 63.6% of the experimental sites. Clinical outcomes were supported by the radiographic analysis showing a bone fill of 3.6 ± 1.9 mm.