A dual-scale micro/nanofibrous PLGA scaffold fabricated by co-electrospinning for regenerative endodontic procedures

The unpredictability of blood clots as natural scaffolds in regenerative endodontic procedures (REPs) has driven the search for synthetic alternatives with reproducible properties. This study aimed to develop and characterize a dual-scale micro/nanofibrous poly(lactic-co-glycolic acid) (PLGA) scaffold fabricated by co-electrospinning and evaluate its physicochemical and biological suitability for REPs under lipopolysaccharide (LPS)-induced inflammatory conditions.

A 7.5% (w/v) PLGA solution was co-electrospun using distinct parameters (flow rate and needle-to-collector distance) to generate a dual-scale fiber architecture. Physicochemical characterization included water uptake, in vitro degradation, and morphological analysis by scanning electron microscopy (SEM). Biological properties were evaluated using human apical papilla cells (APCs). Metabolic activity (Alamar Blue), mineralization (Alizarin Red S), and cell adhesion/morphology (SEM) were assessed in the presence or absence of LPS to simulate an inflammatory environment.

The co-electrospun scaffold showed a hierarchical structure with interconnected micro and nanofibers. Water uptake reached 147.4% within 24 h and increased gradually thereafter. The scaffold showed a biphasic degradation profile-slow initial degradation (21.5% over 28 days) followed by accelerated loss (63.1% at day 45). Hydration induced fiber swelling and pore remodeling. The scaffold supported APC adhesion, spreading, and metabolic activity over 72 h. Under LPS stimulation, APCs maintained metabolic activity and showed robust mineralization potential after 21 days, comparable to the positive control.

The co-electrospun PLGA scaffold showed physicochemical properties compatible with tissue ingrowth and supported APCs function under inflammatory conditions. By providing a controlled microenvironment, it represents a potential scaffold design for future REPs.