Purpose: This study aimed to compare the regenerative potential of bone marrow derived mesenchymal stem cells (BM-MSCS) and breast milk derived mesenchymal stem cells (BrM-MSCS) as pulp capping materials versus to calcium hydroxide (CaOH) at different time intervals. Materials and Methods: 66 middle aged female rabbits were divided into 3 groups according to the pulp capping material (n=22) each group was subdivided into 2 groups according to the assessment time; at 2 weeks and 4 weeks. Group I: rabbits were treated with calcium hydroxide as control. Group II: rabbits were treated with bone marrow mesenchymal stem cells loaded on fibrin gel. Group III: rabbits were treated with breast milk derived mesenchymal stem cells loaded on fibrin gel. Histological examination was performed using light microscope to assess the effect of different pulp capping materials on pulpal regeneration at different time intervals. Data was collected, tabulated and statistically analysed. Results: At two weeks as well as four weeks time intervals, there was a statistically significant difference between different pulp capping materials in percentage of rabbits numbers with different pulpal regeneration. There was a statistical significant increase in percentage of rabbits numbers with complete pulpal regeneration treated with stem cells groups.