Milena Cadenaro1, Luca Fontanive2, Chiara Ottavia Navarra2, Pietro Gobbi3, Annalisa Mazzoni4, Roberto Di Lenarda2, Franklin R Tay5, David H Pashley5, Lorenzo Breschi4. 1. Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, I-34129 Trieste, Italy. Electronic address: mcadenaro@units.it. 2. Department of Medical Sciences, University of Trieste, Piazza dell'Ospitale 1, I-34129 Trieste, Italy. 3. Department of Earth, Life and Environment Sciences (Di.STeVA), University of Urbino, Campus Scientifico Enrico Mattei - Via Ca' Le Suore 2/4, I-61029 Urbino (PU), Italy. 4. Department of Biomedical and Neuromotor Sciences, DIBINEM, University of Bologna, Via San Vitale 59, I-40125 Bologna, Italy. 5. Department of Oral Biology, Georgia Regents University, College of Dental Medicine, Augusta, GA, USA.
Abstract
OBJECTIVES: 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) has been shown to cross-link dentin type I collagen. Increased cross-linking usually elevates the glass transition temperature of polymers. The aim of this study was to evaluate the cross-linking reaction promoted by EDC in different aqueous concentrations by measuring the thermal denaturation temperature (Td) of human dentin collagen. METHODS: The Td of dehydrated collagen and of insoluble dentin matrix collagen immersed in 0.5M or 1M EDC aqueous solution for different treatment times was obtained using a Differential Scanning Calorimeter (DSC). Specimens were also analyzed by Energy Dispersive X-Ray Spectroscopy. RESULTS: EDC-treated dentin collagen showed a significantly higher Td than the untreated specimens when immersed in either 0.5M EDC or 1M EDC for 10min or longer (p<0.05). EDC-treated dentin collagen showed an increase of sulfur and chloride, not detectable in EDC-untreated dentin specimens. Conversely, the relative amount of carbon, nitrogen and oxygen was not modified by treatments. SIGNIFICANCE: EDC-treated dentin collagen showed a higher Td than the untreated control at all tested concentrations and immersion times. A higher Td can be considered an indirect indicator of a more resistant and highly cross-linked collagen network. More data are needed to confirm these results.
OBJECTIVES:1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (EDC) has been shown to cross-link dentin type I collagen. Increased cross-linking usually elevates the glass transition temperature of polymers. The aim of this study was to evaluate the cross-linking reaction promoted by EDC in different aqueous concentrations by measuring the thermal denaturation temperature (Td) of human dentin collagen. METHODS: The Td of dehydrated collagen and of insoluble dentin matrix collagen immersed in 0.5M or 1M EDC aqueous solution for different treatment times was obtained using a Differential Scanning Calorimeter (DSC). Specimens were also analyzed by Energy Dispersive X-Ray Spectroscopy. RESULTS:EDC-treated dentin collagen showed a significantly higher Td than the untreated specimens when immersed in either 0.5M EDC or 1M EDC for 10min or longer (p<0.05). EDC-treated dentin collagen showed an increase of sulfur and chloride, not detectable in EDC-untreated dentin specimens. Conversely, the relative amount of carbon, nitrogen and oxygen was not modified by treatments. SIGNIFICANCE: EDC-treated dentin collagen showed a higher Td than the untreated control at all tested concentrations and immersion times. A higher Td can be considered an indirect indicator of a more resistant and highly cross-linked collagen network. More data are needed to confirm these results.
Authors: Zihou Zhang; Dylan Beitzel; Hessam Majd; Mustafa Mutluay; Arzu Tezvergil-Mutluay; Franklin R Tay; David H Pashley; Dwayne Arola Journal: Dent Mater Date: 2017-09-21 Impact factor: 5.304