Chlorhexidine stabilizes the adhesive interface: A 2-year in vitro study
Received 2 July 2009; accepted 24 November 2009.
Abstract
Objectives
This study evaluated the role of endogenous dentin MMPs in auto-degradation of collagen fibrils within adhesive-bonded interfaces. The null hypotheses tested were that adhesive blends or chlorhexidine digluconate (CHX) application does not modify dentin MMPs activity and that CHX used as therapeutic primer does not improve the stability of adhesive interfaces over time.
Methods
Zymograms of protein extracts from human dentin powder incubated with Adper Scotchbond 1XT (SB1XT) on untreated or 0.2–2% CHX-treated dentin were obtained to assay dentin MMPs activity. Microtensile bond strength and interfacial nanoleakage expression of SB1XT bonded interfaces (with or without CHX pre-treatment for 30s on the etched surface) were analyzed immediately and after 2 years of storage in artificial saliva at 37°C.
Results
Zymograms showed that application of SB1XT to human dentin powder increases MMP-2 activity, while CHX pre-treatment inhibited all dentin gelatinolytic activity, irrespective from the tested concentration. CHX significantly lowered the loss of bond strength and nanoleakage seen in acid-etched resin-bonded dentin artificially aged for 2 years.
Significance
The study demonstrates the active role of SB1XT in dentin MMP-2 activation and the efficacy of CHX inhibition of MMPs even if used at low concentration (0.2%).
cDepartment of SAU&FAL, University of Bologna, Bologna, Italy
dDepartment of SUAN, University “Carlo Bo”, Urbino, Italy
eDepartment of Restorative Dentistry, Piracicaba School of Dentistry, University of Campinas, Piracicaba, Brazil
fBandeirante University of São Paulo (UNIBAN), São Paulo, Brazil
gInstitute of Dentistry, University of Oulu and Oulu University Hospital (OUH), Oulu, Finland
hDepartment of Oral Biology and Maxillofacial Pathology, School of Dentistry, Medical College of Georgia, Augusta, GA, USA
Corresponding author at: Department of Biomedicine, Unit of Dental Sciences and Biomaterials, University of Trieste, Via Stuparich 1, I-34129 Trieste, Italy. Tel.: +39 040 3992192; fax: +39 040 3992665.
ABSTRACT