Antimicrobial photodynamic active biomaterials for periodontal regeneration

Objective: Biomaterials for periodontal regeneration may have insufficient mechanical and antimicrobial properties or are difficult to apply under clinical conditions. The aim of the present study was to develop a polymeric bone grafting material of suitable physical appearance and antimicrobial photodynamic activity. Methods: Two light curable biomaterials based on urethane dimethacrylate (BioM1) and a tri-armed oligoester-urethane methacrylate (BioM2) that additionally contained a mixture of beta-tricalcium phosphate microparticles and 20 wt% photosensitizer mTHPC (PS) were fabricated and analyzed by their compressive strength, flexural strength and modulus of elasticity. Cytotoxicity was observed by incubating eluates and in direct-contact to MC3T3-E1 cells. Antimicrobial activity was ascertained on Porphyromonas gingivalis and Enterococcus faecalis upon illumination with laser light (652 nm, 1 x 100 J/cm(2), 2 x 100 J/cm(2)). Results: The compressive strength, flexural strength and elastic modulus were, respectively, 311.73 MPa, 22.81 MPa and 318.85 MPa for BioM1 + PS and 742.37 MPa, 7.58 MPa and 406.23 MPa for BioM2 + PS. Both materials did not show any cytotoxic behavior. Single laser-illumination (652 nm) caused total suppression of P. gingivalis (BioM2 + PS), while repeated irradiation reduced E. faecalis by 3.7 (BioM1 + PS) and 3.1 (BioM2 + PS) log-counts. Significance: Both materials show excellent mechanical and cytocompatible properties. In addition, irradiation with 652 nm induced significant bacterial suppression. The manufactured biomaterials might enable a more efficient cure of periodontal bone lesions. Due to the mechanical properties functional stability might be increased. Further, the materials are antimicrobial upon illumination with light that enables a trans-mucosal eradication of residual pathogens. Crown Copyright (C) 2018 Published by Elsevier Inc. on behalf of The Academy of Dental Materials. All rights reserved.