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Bacterial biofilms associated with implants remain a significant source of infections in dental, implant, and other healthcare industries due to challenges in biofilm removal. Biofilms consist of bacterial cells surrounded by a matrix of extracellular polymeric substance (EPS), which protects the colony from many countermeasures, including antibiotic treatments. Biofilm EPS composition is also affected by environmental factors. In the oral cavity, the presence of sucrose affects the growth of Streptococcus mutans that produce acids, eroding enamel and forming dental caries. Biofilm formation on dental implants commonly leads to severe infections and failure of the implant. This work determines the effect of sucrose concentration on biofilm EPS formation and adhesion of Streptococcus mutans, a common oral colonizer. Bacterial biofilms are grown with varying concentrations of sucrose on titanium substrates simulating dental implant material. Strategies for measuring adhesion for films such as peel tests are inadequate for biofilms, which have low cohesive strength and will fall apart when tensile loading is applied directly. The laser spallation technique is used to apply a stress wave loading to the biofilm, causing the biofilm to delaminate at a critical tensile stress threshold. Biofilm formation and EPS structures are visualized at high magnification with scanning electron microscopy (SEM). Sucrose enhanced the EPS production of S. mutans biofilms and increased the adhesion strength to titanium, the most prevalent dental implant material. However, there exists a wide range of sucrose concentrations that are conducive for robust formation and adhesion of S. mutans biofilms on implant surfaces.
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Chemoselective Coatings of GL13K Antimicrobial Peptides for Dental Implants
Dental implant−associated infection is a clinical challenge which poses a significant healthcare and socio−economic burden. To overcome this issue, developing antimicrobial surfaces, including antimicrobial peptide coatings, has gained great attention. Different physical and chemical routes have been used to obtain these biofunctional coatings, which in turn might have a direct influence on their bioactivity and functionality. In this study, we present a silane−based, fast, and efficient chemoselective conjugation of antimicrobial peptides (Cys−GL13K) to coat titanium implant surfaces. Comprehensive surface analysis was performed to confirm the surface functionalization of as−prepared and mechanically challenged coatings. The antibacterial potency of the evaluated surfaces was confirmed against both Streptococcus gordonii and Streptococcus mutans, the primary colonizers and pathogens of dental surfaces, as demonstrated by reduced bacteria viability. Additionally, human dental pulp stem cells demonstrated long−term viability when cultured on Cys−GL13K−grafted titanium surfaces. Cell functionality and antimicrobial capability against multi−species need to be studied further; however, our results confirmed that the proposed chemistry for chemoselective peptide anchoring is a valid alternative to traditional site−unspecific anchoring methods and offers opportunities to modify varying biomaterial surfaces to form potent bioactive coatings with multiple functionalities to prevent infection.
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- Award ID(s):
- 2011401
- PAR ID:
- 10506830
- Publisher / Repository:
- Pharmaceutics
- Date Published:
- Journal Name:
- Pharmaceutics
- Volume:
- 15
- Issue:
- 10
- ISSN:
- 1999-4923
- Page Range / eLocation ID:
- 2418
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.3390/pharmaceutics15102418
