Physicochemical, Mechanical and Biological Characterization of a PCL/PLA-Based Biocomposite for Potential Dental Post Applications in Primary Teeth

Early childhood caries frequently affects maxillary anterior primary teeth, and their rehabilitation remains a clinical challenge due to the lack of suitable resorbable intracanal posts. This study aimed to develop and characterize a biodegradable polymer-ceramic biomaterial for potential application in primary tooth rehabilitation. Polycaprolactone (PCL) and polylactic acid (PLA) composite filaments (50:50), reinforced with 20 wt.% α-tricalcium phosphate and 5 wt.% zirconia, were produced using two different processing routes involving a Noztek Touch and a Brabender Plasti-Corder extruder. The developed biocomposites obtained by single extrusion with a Brabender Plasti-Corder exhibited good ceramic distribution in the polymeric matrix but exhibited lower mean compressive modulus values (155.98 MPa vs. 258.44 MPa), which were not statistically significant. The composite biomaterial showed degradation under alkaline conditions, whereas only limited mass loss was observed under acidic conditions and in hydrogen peroxide, with minimal mass loss in distilled water. These composites showed favorable biocompatibility with dental pulp stem cells, although no antimicrobial activity was observed. Furthermore, the incorporation of zirconia may contribute to radiopacity for radiographic monitoring. These findings support the potential of the developed composite biomaterial as a candidate biodegradable intracanal post for pediatric restorative dentistry applications.