Mechanical properties and modeling of drug release from chlorhexidine-containing etch-and-rinse adhesives

Rodrigo Stanislawczuk; Alessandra Reis; Pamela Malaquias; Fabiane Pereira; Paulo Vitor Farago; Marcia Margarete Meier; Alessandro D Loguercio

doi:10.1016/j.dental.2014.01.007

Mechanical properties and modeling of drug release from chlorhexidine-containing etch-and-rinse adhesives

Dent Mater. 2014 Apr;30(4):392-9. doi: 10.1016/j.dental.2014.01.007. Epub 2014 Feb 14.

Authors

Rodrigo Stanislawczuk¹, Alessandra Reis², Pamela Malaquias³, Fabiane Pereira³, Paulo Vitor Farago⁴, Marcia Margarete Meier⁵, Alessandro D Loguercio⁶

Affiliations

¹ Department of Restorative Dentistry, Center of Higher Education of Campos Gerais, Ponta Grossa, Brazil.
² Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil.
³ School of Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil.
⁴ Department of Pharmaceutical Sciences, State University of Ponta Grossa, Ponta Grossa, Brazil.
⁵ Department of Chemistry, State University of Santa Catarina, Joinville, Brazil.
⁶ Department of Restorative Dentistry, State University of Ponta Grossa, Ponta Grossa, Brazil. Electronic address: aloguercio@hotmail.com.

PMID: 24529533
DOI: 10.1016/j.dental.2014.01.007

Abstract

Objectives: To evaluate the effects of chlorhexidine (CHX) addition in different concentrations into simplified etch-and-rinse adhesives on the ultimate tensile strength (UTS), water sorption (WS), solubility (SO) and the rate of CHX release over time.

Methods: We added CHX diacetate to Ambar [AM] (FGM) and XP Bond [XP] (Dentsply) in concentrations of 0, 0.01, 0.05, 0.1 and 0.2 wt%. For UTS (n=10 for each group), adhesive specimens were constructed in an hourglass shape metallic matrix with cross-sectional area of 0.8 mm(2). Half of specimens were tested after 24 h and the other half after 28 days of water storage in tension of 0.5 mm/min. For WS and SO (n=10 for each group), adhesive discs (5.8 mm×1.0 mm) were prepared into a mold. After desiccation, we weighed and stored the cured adhesive specimens in distilled water for evaluation of the WS, SO and the cumulative release of CHX over a 28-day period. For CHX release (n=10 for each group), spectrophotometric measurements of storage solution were performed to examine the release kinetics of CHX. We subjected data from each test to ANOVA and Tukey' test (α=0.05).

Results: XP Bond adhesive showed significantly more WS and SO and lower UTS than Ambar. In general, the addition of CHX did not alter WS, SO and UTS of the adhesives. XP showed a higher CHX release than AM (p<0.05) in all concentrations and the final amount of CHX release was directly proportional to the initial CHX concentration added to the adhesives. After 28 days of water storage, approximately 20% of CHX was released from XP and 8.0-12.0% from AM.

Conclusions: Addition of CHX to commercial adhesive is a feasible method to provide a controlled release of CHX over time without jeopardizing WS, SO and UTS of the adhesives.

Significance: Manufacturers should consider adding CHX to commercial adhesives to provide a controlled release of CHX over time.

Keywords: Adhesives systems; Chlorhexidine; Chlorhexidine release; Solubility; Ultimate tensile strength; Water sorption.

MeSH terms

Acid Etching, Dental
Chlorhexidine / chemistry*
Dentin-Bonding Agents / chemistry*
Drug Liberation
Materials Testing
Methacrylates / chemistry*
Solubility
Tensile Strength
Water / chemistry

Substances

Ambar
Dentin-Bonding Agents
Methacrylates
XP-Bond
Water
Chlorhexidine