Dental pulp polyps contain stem cells comparable to the normal dental pulps

Area of Science:

• Dental regenerative medicine
• Stem cell biology
• Oral pathology

Background:

• Few studies have explored stem cell isolation from pathologically injured dental tissues.
• Pulp polyps, resulting from chronic hyperplastic pulpitis, represent a unique pathological dental tissue.
• Investigating stem cells in pulp polyps could reveal novel therapeutic sources.

Purpose of the Study:

• To assess the feasibility of isolating stem cells from pulp polyps.
• To characterize the isolated cells and compare them to healthy Dental Pulp Stem Cells (DPSCs).
• To determine if pulp polyp-derived cells meet the criteria for Multipotent Mesenchymal Stromal Cells (MSCs).

Main Methods:

• Pulp polyp tissues were enzymatically digested to harvest single cells for culture.
• Isolated cells were induced to differentiate into adipocytes and osteoblasts.
• Flow cytometry was used to analyze cell surface markers (CD90, CD73, CD105, CD45, CD14).
• Colonigenic efficacy and population doubling time were compared to DPSCs.

Main Results:

• Cells isolated from pulp polyps showed spindle-shaped morphology and successfully differentiated into adipocytes and osteoblasts.
• These cells expressed MSC markers (CD90, CD73, CD105) and were negative for hematopoietic markers (CD45, CD14).
• While normal DPSCs had higher colony-forming efficiency, pulp polyps yielded a comparable total number of stem cells per sample due to larger tissue size.

Conclusions:

• Cells isolated from pulp polyps fulfill the minimal criteria for MSC definition.
• Pulp polyps can serve as a potential source of stem cells, acquired non-invasively.
• This finding expands the understanding of stem cell reservoirs in pathological dental tissues.