Silver nanoparticles Dental materials – What’s new?

Silver nanoparticles are starting to be used in dental materials of all sorts.  Well experimentally, anyway.  There has been a bit of an uptick in research being put out and most of it looks very promising.  Silver particles are already being used as antimicrobial agents for wound dressing, cardiac prostheses, and bone prostheses.  Dental composite resins, tissue conditioners, acrylic resins, and mouth rinses are some of the products that contain silver zeolite.

How do silver nanoparticles (AgNPs) work and are they safe?

Silver nanoparticles work by destroying bacterial basement membranes and increasing permeability when in direct contact.  Silver produces antibacterial effects by interacting with various proteins.  Since AgNPs are  toxic, the major issue is keeping the levels of silver ions released to a minimum.  Another issue is maintaining the materials desired properties.  Ideally a product would contain a high enough concentration to inhibit bacterial growth, but not release silver ions at all.  Our diets have a natural amount of silver in the range of 7µg Gibson 83 up to a range of 20-80µg reference.

Silver nanoparticles in orthodontics

AgNPs were added to the acrylic of removable retainers and the resulting Streptococcus mutans colonies dropped by 40%. Farhadian 2016 AJO-DO

Silver nanoparticles in endodontics

SDF (Silver Diamine Fluoride) could be used as an interappointment dressing, however the tooth will likely stain black so needs to be a molar.  Hiraishi JOE 2010 Furthermore mixing AgNPs with tradional CaOH gives even better results. AlGazlan JOE 2022

AgNP effective as dressing but not as irrigant Wu 2014 JOE

Using silver nanoparticles in a rinse solution appears to be similar in effectiveness as NaOCl. Gonzalez-Luna 2016 J Nanomaterials

Silver nanoparticles dental materials generic

Dental sealants with silver nanoparticles (AgNPs)

Silver zirconium phosphate (AgZrPO4) in dental resins significantly inhibits S. mutans. Thaweboon 2016

Dental resins with AgNPs

The addition of β-AgVO₃ can provide acrylic resins with antibacterial activity but reduces their impact strength.  de Castro 2016 JPD

Dental adhesives with AgNPs

Single Bond Universal holds up better under thermocycling and has excellent antibacterial activity. Wang JPD 2022

Alginate materiel with AgNPs

Adding AgNPs to irreversible hydrocolloid impression materials resulted in superior antimicrobial activity without adversely affecting their properties. Ginjupalli JPD 2016.  Seems like of all the dental materials containing silver nanoparticles, this one sounds the most promising.

Denture liner material with AgNPs

Modification of soft liner materials with silver nanoparticles results in a material that should be capable of preventing colonization of Candida albicans.  Chladek 2011 Int J Mol Sci.  The same author is clearly looking at perfecting this product.  In addition to his first article, he later published results testing acceptable concentrations that would not effect properties. Chladek 2013 Int J Mol Sci.  Also, Nam 2011 J Adv Pro did similar work to Chladek’s first study.

Maxillofacial prosthesis with silver nanoparticles

Chong JPD 2022 shows that it is effective in silicone as a antimicrobial.

Silver nanoparticles dental materials – A match waiting to happen?  We’ll see!!

Other nanoparticles used in dentistry that we might make a blog about.

Quaternary ammonium polyethyleneimine (QPEI) in resin for antimicrobial effect.

• It will not leach out or impact mechanical properties. Beyth Biomaterials 2006
• QPEI will maintain it’s bacterial properties even after polishing the resin.  Pietrokovski JPD 2016