Effect of a novel quaternary ammonium methacrylate polymer (QAMP) on adhesion and antibacterial properties of dental adhesives.
This study investigated the resin-dentin bond strength (μTBS), degree of conversion (DC), and antibacterial potential of an innovative adhesive system containing a quaternary ammonium methacrylate polymer (QAMP) using in situ and in vitro assays. Forty-two human third molars were flattened until the dentin was exposed and were randomly distributed into three groups of self-etching adhesive systems: Clearfil™ SE Bond containing 5% QAMP (experimental group), Clearfil™ Protect Bond (positive control) and Clearfil™ SE Bond (negative control). After light curing, three 1 mm-increments of composite resin were bonded to each dentin surface. A total of thirty of these bonded teeth (10 teeth per group) was sectioned to obtain stick-shaped specimens and tested under tensile stress immediately, and after 6 and 12 months of storage in distilled water. Twelve bonded teeth (4 teeth per group) were longitudinally sectioned in a mesio-to-distal direction to obtain resin-bonded dentin slabs. In situ DC was evaluated by micro-Raman spectroscopy. In vitro DC of thin films of each adhesive system was measured using Fourier transform infrared spectroscopy. In vitro susceptibility tests of these three adhesive systems were performed by the minimum inhibitory/minimum bactericidal concentration (MIC/MBC) assays against Streptococcus mutans, Lactobacillus casei, and Actinomyces naeslundii. No statistically significant difference in μTBS was observed between Clearfil™ SE Bond containing 5% QAMP and Clearfil™ SE Bond (p>0.05) immediately, and after 6 and 12 months of water storage. However Clearfil™ Protect Bond showed a significant reduction of μTBS after 12 months of storage (p=0.039). In addition, QAMP provided no significant change in DC after incorporating into Clearfil™ SE Bond (p>0.05). Clearfil™ SE Bond containing 5% QAMP demonstrated MIC/MBC values similar to the positive control against L. casei and A. naeslundii and higher than the negative control for all evaluated bacterial strains. The use of QAMP in an adhesive system demonstrated effective bond strength, a suitable degree of conversion, and adequate antibacterial effects against oral bacteria, and may be useful as a new approach to provide long-lasting results for dental adhesives.
Postgraduate Program in Dentistry, Department of Dentistry, State University of Ponta Grossa, Paraná 84030-900, Brazil. yasminemendes@hotmail.com.
Yasmine M
YM
Pupo
Laboratory of Pharmaceutical Products, Postgraduate Program in Pharmaceutical Sciences, Department of Pharmaceutical Sciences, State University of Ponta Grossa, Paraná 84030-900, Brazil. pvfarago@uepg.br.
Paulo Vitor
PV
Farago
Laboratory of Pharmaceutical Products, Postgraduate Program in Pharmaceutical Sciences, Department of Pharmaceutical Sciences, State University of Ponta Grossa, Paraná 84030-900, Brazil. jessicabem@hotmail.com.
Jessica M
JM
Nadal
Multi-user Laboratory, State University of Ponta Grossa, Paraná 84030-900, Brazil. luziachaves4@hotmail.com.
Luzia C
LC
Simão
Laboratory of Clinical Microbiology, Department of Clinical and Toxicological Analysis, State University of Ponta Grossa, Paraná, 84030-900, Brazil. esmerino@uepg.br.
Luís Antônio
LA
Esmerino
Postgraduate Program in Dentistry, Department of Dentistry, State University of Ponta Grossa, Paraná 84030-900, Brazil. osnaramgomes@uol.com.br.
Osnara M M
OM
Gomes
Postgraduate Program in Dentistry, Department of Dentistry, State University of Ponta Grossa, Paraná 84030-900, Brazil. gomesjoaocarlos@uol.com.br.
João Carlos
JC
Gomes
D000190:Actinomyces / Q000187:drug effects; D003188:Composite Resins / Q000737:chemistry / Q000494:pharmacology; D055117:Curing Lights, Dental; D001840:Dental Bonding; D003738:Dental Cements / Q000737:chemistry* / Q000494:pharmacology; D006801:Humans; D007780:Lacticaseibacillus casei / Q000187:drug effects; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry*; D008826:Microbial Sensitivity Tests; D011108:Polymers / Q000737:chemistry*; D000644:Quaternary Ammonium Compounds / Q000737:chemistry*; D013295:Streptococcus mutans / Q000187:drug effects; D013499:Surface Properties; D013718:Tensile Strength; D013997:Time Factors
D003188:Composite Resins; D003738:Dental Cements; D008689:Methacrylates; D011108:Polymers; D000644:Quaternary Ammonium Compounds