title: Physical properties of self-, dual-, and light-cured direct core materials.
abstract: The objective of this study is to evaluate flexural strength, flexural modulus, compressive strength, curing temperature, curing depth, volumetric shrinkage, water sorption, and hygroscopic expansion of two self-, three dual-, and three light-curing resin-based core materials. Flexural strength and water sorption were measured according to ISO 4049, flexural modulus, compressive strength, curing temperature, and curing depth according to well-proven, literature-known methods, and the volumetric behavior was determined by the Archimedes' principle. ANOVA was calculated to find differences between the materials' properties, and correlation of water sorption and hygroscopic expansion was analysed according to Pearson (p < 0.05). Clearfil Photo Core demonstrated the highest flexural strength (125 ± 12 MPa) and curing depth (15.2 ± 0.1 mm) and had the highest flexural modulus (≈12.6 ± 1.2 GPa) concertedly with Multicore HB. The best compressive strength was measured for Voco Rebilda SC and Clearfil DC Core Auto (≈260 ± 10 MPa). Encore SuperCure Contrast had the lowest water sorption (11.8 ± 3.3 µg mm(-3)) and hygroscopic expansion (0.0 ± 0.2 vol.%). Clearfil Photo Core and Encore SuperCure Contrast demonstrated the lowest shrinkage (≈2.1 ± 0.1 vol.%). Water sorption and hygroscopic expansion had a very strong positive correlation. The investigated core materials significantly differed in the tested properties. The performance of the materials depended on their formulation, as well as on the respective curing process.
authors.affiliation: Medical Faculty, Centre of Dentistry, Department of Operative and Preventive Dentistry and Endodontics, Heinrich-Heine-University, Moorenstr. 5, Geb. 18.13, 40225 Düsseldorf, Germany.
authors.forename: Stefan
authors.initials: S
authors.lastname: Rüttermann
authors.forename: Ian
authors.initials: I
authors.lastname: Alberts
authors.forename: Wolfgang H M
authors.initials: WH
authors.lastname: Raab
authors.forename: Ralf R
authors.initials: RR
authors.lastname: Janda
mesh_terms: D000042:Absorption; D000327:Adsorption; D017438:Bisphenol A-Glycidyl Methacrylate / Q000737:chemistry; D055598:Chemical Phenomena; D003188:Composite Resins / Q000737:chemistry*; D019245:Compressive Strength; D003764:Dental Materials / Q000737:chemistry*; D017220:Dentin-Bonding Agents / Q000737:chemistry; D055119:Elastic Modulus; D006801:Humans; D055115:Light-Curing of Dental Adhesives; D008422:Materials Testing; D008689:Methacrylates / Q000737:chemistry; D018583:Pliability; D011092:Polyethylene Glycols / Q000737:chemistry; D058105:Polymerization; D011109:Polymethacrylic Acids / Q000737:chemistry; D011140:Polyurethanes / Q000737:chemistry; D019279:Resin Cements / Q000737:chemistry; D055116:Self-Curing of Dental Resins; D013314:Stress, Mechanical; D013499:Surface Properties; D044366:Transition Temperature; D014867:Water / Q000737:chemistry; D017155:Wettability
chemical_list: C469237:Clearfil Core; D003188:Composite Resins; D003764:Dental Materials; D017220:Dentin-Bonding Agents; D008689:Methacrylates; C509715:MultiCore Flow; D011109:Polymethacrylic Acids; D011140:Polyurethanes; D019279:Resin Cements; C529053:rebilda DC; D014867:Water; C074669:Clearfil Photo Bond; C029824:urethane dimethacrylate luting resin; C020946:triethylene glycol dimethacrylate; D011092:Polyethylene Glycols; D017438:Bisphenol A-Glycidyl Methacrylate