From Extraction to Cryobanking: Which Critical Process Parameters Genuinely Improve DPSC Production?

Background

Advanced therapy medicinal products (ATMPs) require strict control of critical process parameters (CPPs) to ensure manufacturing efficiency. The relative impact of donor systemic factors, such as vitamin D status, versus technical process parameters on dental pulp-derived stem cell (DPSC) production remains unclear.

Methods

In this prospective observational study, 250 adults undergoing extraction of impacted mandibular third molars were included. Dental pulp was processed under a standardized SOP using different preparation methods and enzyme conditions. Primary endpoints were serum 25(OH)D concentration and cell yield; secondary endpoints included number of passages and cryovials.

Results

Mean 25(OH)D concentration was 30.1 ± 14.5 ng/mL and was higher in supplemented individuals (38.2 ± 14.0 vs. 25.6 ± 12.7 ng/mL; p < 0.0001) but was not associated with cell yield (ρ = 0.14, p = 0.168) or passages (ρ = 0.07, p = 0.406). In contrast, process parameters showed strong effects: scissor preparation resulted in a substantially higher yield than mechanical methods (median 5.00 vs. 1.00 million cells; p = 3.6 × 10-13), and type II collagenase was independently associated with a higher yield (+2.04 million cells; p = 0.026). The number of passages was the strongest predictor of yield (β = 2.28 million per passage; p < 10-26). Post-thaw viability remained high (mean 90.1% and range 81-98%).

Conclusions

Manufacturing efficiency of DPSCs is primarily determined by critical process parameters, particularly preparation method, enzyme selection, and passage control, whereas donor vitamin D status did not significantly influence outcomes under the studied SOP. These findings highlight process standardization as the key driver of reproducible ATMP manufacturing.