A new resin-bonded retrograde filling material.

Department of Conservative Dentistry, Asan Medical Center, Ulsan University, Seoul, Korea.
Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology (Impact Factor: 1.5). 11/2009; 108(5):e111-6. DOI: 10.1016/j.tripleo.2009.07.020
Source: PubMed

ABSTRACT This study determined the physical properties and cytotoxicity of a novel root-end filling material (NRC).
NRC is a powder and liquid system. The liquid is composed of hydroxyethylmethacrylate, benzoyl peroxide, toluidine, and toluenesulfinate. And the powder is made of calcium oxide, calcium silicate, and triphenylbismuth carbonate. The setting time, compressive strength, and pH change of NRC and gray and white mineral trioxide aggregate (MTA) were determined according to ISO standardization. MC3T3-E1 cells were cultured on NRC and white MTA for determining MTT scores. The absorbance of formazan was measured at 570 nm with a spectrophotometer. The MTT assay was performed in triplicate and repeated in 2 cultures. One-way analysis of variance was used to determine statistical differences in physical properties and MTT assay (P < .05).
Mean setting time of materials tested were: NRC 12.5 +/- 0.3 minutes, gray MTA 345.5 +/- 96.2 minutes, and white MTA 318.0 +/- 56.0 minutes. After 24 hours, the mean compressive strengths were: NRC, 21.6 +/- 5.5 MPa, gray MTA: 7.7 +/- 3.3 MPa, and white MTA, 18.9 +/- 3.2 MPa. The pH of the test materials were: NRC 12.0, gray MTA 12.2, and white MTA 11.9. There were no statistically significant differences in compressive strength and pH between white MTA and NRC. The compressive strength of gray MTA was significantly lower than white MTA and NRC (P < .05). The setting time of NRC was significantly lower than white and gray MTA. In MTT assay, both NRC and white MTA were not cytotoxic to MC3T3-E1 cells.
It was concluded that the setting time, compressive strength, pH, and initial biocompatibility results of NRC are favorable for a root-end filling material.

  • [Show abstract] [Hide abstract]
    ABSTRACT: This study examined whether 4-methacryloxyethyl trimellitate anhydride/methylmethacrylate-tri-n-butyl borane (4-META/MMA-TBB) resin can be used with mineral trioxide aggregate (MTA) to overcome MTA's shortcomings. The biologic reactions of the mixture of MTA powder and 4-META/MMA-TBB resin (MTA/4-META) and its potential in clinical applications were also investigated. MTA powder was mixed with 4-META/MMA-TBB resin instead of water at the appropriate proportions determined by a series of studies prior to this experiment. MTA powder mixed with sterile water was used as control. The setting time, compressive strength, pH, and dye leakage of MTA/4-META and MTA were assessed by Gilmore apparatus, universal mechanical testing machine, pH meter, and methylene blue penetration method, respectively. Cytotoxicity also was evaluated by MTT assay with MC3T3-E1 cells. The setting time of MTA/4-META was significantly lower than that of MTA: 11.2 ± 0.8 minutes versus 318 ± 56.0 minutes, respectively (P < .05). The mean compressive strength of MTA/4-META after 24 hours was significantly higher than that of MTA: 57.4 ± 11.6 MPa versus 18.7 ± 3.0 MPa, respectively (P < .05). MTA/4-META showed significantly less leakage than MTA (P < .05). The initial pHs for MTA and MTA/4-META at 2 hours were 10.73 ± 0.95 and 10.08 ± 0.13, respectively, and reached plateaus of 10.92 ± 0.31 and 10.54 ± 0.39 at 24 hours, respectively. The pH of MTA was higher than that of MTA/4-META in the entire period, but the differences were only significant up to 48 hours (P < .05). MTA and MTA/4-META both showed no cytotoxicity. 4-META/MMA-TBB resin as a mixing vehicle of MTA powder can improve the setting and handling properties of MTA and may maintain or improve its other biophysical properties.
    Oral Surgery, Oral Medicine, Oral Pathology, Oral Radiology, and Endodontology 07/2011; 112(5):e6-11. · 1.50 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: New resin cement (NRC) has been developed as a root repairing material and the material is composed of organic resin matrix and inorganic powders. The aim of this study was to compare the rat subcutaneous tissue response to NRC and mineral trioxide aggregate (MTA) cement and to investigate the tissue toxicity of both materials. Sixty rats received two polyethylene tube-implants in dorsal subcutaneous regions, MTA and NRC specimens. Twenty rats were sacrificed respectively at 1, 4 and 8 wk after implantation and sectioned to 5 µm thickness and stained with Hematoxylin-Eosin (H-E) or von-Kossa staining. The condition of tissue adjacent to the implanted materials and the extent of inflammation to each implant were evaluated by two examiners who were unaware of the type of implanted materials in the tissues. Data were statistically analyzed with paired t-test (p < 0.05). In specimens implanted with both NRC and MTA, severe inflammatory reactions were present at one wk, which decreased with time. At eighth wk, MTA implanted tissue showed mild inflammatory reaction, while there were moderate inflammatory reactions in NRC implanted tissue, respectively. In NRC group, von-Kossa staining showed more calcification materials than MTA group at eighth wk. It was concluded that the calcium reservoir capability of NRC may contribute to mineralization of the tissues.
    Restorative dentistry & endodontics. 11/2012; 37(4):194-200.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The purpose of a root-end filling is to establish a seal between the root canal space and the periradicular tissues. As root-end filling materials come into contact with periradicular tissues, knowledge of the tissue response is crucial. Almost every available dental restorative material has been suggested as the root-end material of choice at a certain point in the past. This literature review on root-end filling materials will evaluate and comparatively analyse the biocompatibility and tissue response to these products, with primary focus on newly introduced materials.
    Restorative dentistry & endodontics. 08/2013; 38(3):119-127.