title: A comparison study on the flexural strength and compressive strength of four resin-modified luting glass ionomer cements.
abstract: The purpose of this study is to compare the differences in flexural strength and compressive strength between four resin-modified luting glass ionomer cements that are commonly used in clinics. Furthermore, this study investigates the influence of curing mode on the flexural strength and compressive strength of dual-cured resin-modified glass ionomer cements. Initially, flexural strength and compressive strength test specimens were prepared for RL, NR, GCP, and GCC. The RL group and NR group were cured by the light-curing mode and chemical-curing mode. Five specimens were prepared for each test group, and the flexural strength and compressive strength of each were measured. Data were analyzed by one-way ANOVA with SPSS 13.0. Furthermore, the fracture morphology of the flexural specimens was observed by SEM. The result of the mean flexural strength of each group is as follows: the NR light-cured group > NR chemically-cured group > GCP > RL light-cured group > GCC > RL chemically-cured group. More specifically, the flexural strength of the NR light-cured group ((42.903±4.242) MPa) is significantly higher (P<0.05) than those of the other groups, and in addition, the flexural strength of the light-curing mode is significantly higher (P<0. 05) than that of both the NR and RL chemically-cured groups. The result of the mean compressive strength of each group is as follows: GCP > NR chemically-cured group > NR light-cured group > GCC > RL light-cured group > RL chemically-cured group. Although the compressive strengths of the NR and GCP groups are higher than those of the GCC and RL groups, there are no significant differences (P>0.05) between NR and GCP, and no significant differences between GCC and RL. Furthermore, there are no significant differences (P>0.05) between the two curing modes on NR and RL. From the present study, it can be concluded that NR has superior flexural strength and compressive strength compared to the other three materials. Additionally, the curing mode can affect the flexural strength of dual-cured RMGIC because with the light-curing mode, the flexural strength is higher than with the chemical-curing mode. Therefore, light curing is an essential procedure when using dual-cured RMGIC in clinics.
authors.affiliation: Department of Dental Materials, Dental Medical Devices Testing Center, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University, Beijing, China.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Li
authors.affiliation: Department of Dental Materials, Dental Medical Devices Testing Center, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University, Beijing, China.
authors.forename: Hong
authors.initials: H
authors.lastname: Lin
authors.affiliation: Department of Dental Materials, Dental Medical Devices Testing Center, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University, Beijing, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Zheng
authors.affiliation: Department of Dental Materials, Dental Medical Devices Testing Center, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University, Beijing, China.
authors.forename: Xuehui
authors.initials: X
authors.lastname: Zhang
authors.affiliation: Department of Dental Materials, Dental Medical Devices Testing Center, Peking University School and Hospital of Stomatology, Beijing, China.|National Engineering Laboratory for Digital and Material Technology of Stomatology, Peking University, Beijing, China.
authors.forename: Yongxiang
authors.initials: Y
authors.lastname: Xu
mesh_terms: D000268:Adhesiveness; D019245:Compressive Strength; D003738:Dental Cements / Q000737:chemistry*; D055119:Elastic Modulus; D005899:Glass Ionomer Cements / Q000737:chemistry*; D006244:Hardness; D055115:Light-Curing of Dental Adhesives / Q000379:methods*; D008422:Materials Testing; D012117:Resins, Synthetic / Q000737:chemistry*; D055116:Self-Curing of Dental Resins / Q000379:methods*; D013718:Tensile Strength
chemical_list: D003738:Dental Cements; D005899:Glass Ionomer Cements; D012117:Resins, Synthetic
keywords: Resin-modified glass ionomer cements; compressive strength; curing mode; flexural strength; light cured and chemical cured