Electrospun poly(l-lactide) nanofibers coated with mineral trioxide aggregate enhance odontogenic differentiation of dental pulp stem cells

A combination of bioceramics and nanofibrous scaffolds holds promising potential for inducing of mineralization in connective tissues. The aim of the present study was to investigate the attachment, proliferation and odontogenic differentiation of dental pulp stem cells (DPSC) on poly(l-lactide) (PLLA) nanofibers coated with mineral trioxide aggregate (MTA). Polymeric scaffolds were fabricated via the electrospinning method and their surface was coated with MTA. DPSC were isolated from dental pulp and their biological behavior was evaluated on scaffolds and the control group using MTT assay. Alkaline phosphatase (ALP) activity, biomineralization and the expression of odontogenic genes were analyzed during odontogenic differentiation. Isolated DPSC showed spindle-shaped morphology with multi-lineage differentiation potential and were positive for CD73, CD90 and CD105. MTA-coated PLLA (PLLA/MTA) exhibited nanofibrous structure with average fiber diameter of 756 +/- 157 nm and interconnected pores and also suitable mechanical properties. Similar to MTA, these scaffolds were shown to be biocompatible and to support the attachment and proliferation of DPSC. ALP activity transiently peaked on day 14 and was significantly higher in PLLA/MTA scaffolds than in the control groups. In addition, increasing biomineralization was observed in all groups with a higher amount in PLLA/MTA. Odontogenic-related genes, DSPP and collagen type I showed a higher expression in PLLA/MTA on days 21 and 14, respectively. Taken together, MTA/PLLA electrospun nanofibers enhanced the odontogenic differentiation of DPSC and showed the desired characteristics of a pulp capping material.

Automated summary

The combination of bioceramics and nanofibrous scaffolds shows potential for inducing mineralization in connective tissues. The study investigated the behavior of dental pulp stem cells (DPSC) on mineral trioxide aggregate (MTA) coated poly(l-lactide) (PLLA) nanofibers, showing enhanced odontogenic differentiation with desired characteristics for pulp capping materials.