ABSTRACT
Objective To evaluate the effects of marginal adaptation with different materials on restoring dental wedge-shaped defects. Methods From January 2016 to July 2016,80 patients with 172 wedge -shaped defect teeth in Stomatological Hospital of Haishu District were chosen and randomly divided into three groups accord-ing to random number table method,26 patients with 55 defect teeth were treated with Fuji glass ionomer( group A) , 23 patients with 59 defect teeth were treated with Carey charismatic light-cured composite resin( group B) ,and the other 31 patients with 58 defect teeth were treated with beautifil flow plus reinforced polymer F03(group C). Marginal adaptation of three groups of different materials of the teeth were measured. Results The micro -leakage depth among the three groups had statistically significant difference(H=7. 036,P=0. 035). The micro-leakage depth of group A,B and C were (1. 10 ± 0. 05) mm,(0. 96 ± 0. 05) mm,(0. 78 ± 0. 06) mm,respectively. There was statisti-cally significant difference among the three groups(F=22. 371,P=0. 005). Conclusion The marginal adaptation of beautifil flow plus reinforced polymer F03 is superior to FujiⅡglass-ionome and Charisma composite resin,and has benefits for treatment of wedge-shaped defects.
ABSTRACT
The purpose of this study was to evaluate the color stability of light cured composite resins according to the resin matrices. Three kinds of resin matrices such as Bis-GMA (Venus® Diamond; VD), Silorane (FiltekTM P90; P90), and Ormocer (Admira; Ad) were selected. Each of them were used to prepare 30 specimens. The initial CIE L*a*b* values were measured by means of a Spectrophotometer (NF999, Nippon Denshoku, Japan). For accelerated aging process, the specimens were immersed in a circulating water bath with distilled water at 60℃. Spectrophotometric analyses were made after immersion of 8, 16, 24, 41 days and the color difference (ΔE*) was calculated. The L* value increased compared with initial L* value. VD had the greatest L* value change and Ad had the smallest L* value change (p<0.05). Ad had the greatest a* value change and VD had the smallest a* value change (p<0.05). The b* value of P90 increased steadily in positive value (+)(p<0.05). ΔE* of Ad had the smallest value and that of P90 had the greatest change with time. According to this study, the value of light cured composite resins was increased with water sorption and color of those changed into greenish and yellowish. And according to the evaluation of color stability, Ad with Ormocer as resin matrices had the best color stability with time in oral environment and P90 with Silorane as resin matrices had the lowest color stability with time. And VD had the greatest initial ΔE*.
Subject(s)
Aging , Baths , Bisphenol A-Glycidyl Methacrylate , Composite Resins , Diamond , Immersion , Organically Modified Ceramics , Silorane Resins , WaterABSTRACT
302 teeth with wedge-shaped defect in 168 patients were restored by SDR(smart dentin replacement,n =112),glass ionomer (n =98) and light-cured composite resin(n =92) respectively.12 to 15 month follow-up showed the success rate was 96.2％,84.8％ and 86.2％ respectively(P ＜ 0.01).SDR is an ideal material in restoring wedge-shaped defect.
ABSTRACT
OBJECTIVES: This study investigated the effects of the color components of light-cured composite resin before and after polymerization on degree of conversion (DC) and biaxial flexural strength (FS). MATERIALS AND METHODS: Four enamel shades (A1, A2, A3, A4) and two dentin shades (A2O, A3O) of Premisa (Kerr Co.) and Denfil (Vericom Co.) were evaluated on their CIE L*, a*, b* color components using the spectrophotometer before curing, after curing and at 7 day. The DC of same specimens were measured with Near-infrared spectrometer (Nexus, Thermo Nicolet Co.) at 2 hr after cure and at 7 day. Finally, the FS was obtained after all the other measurements were completed at 7 day. The correlations between each color component and DC and FS were evaluated. RESULTS: The light-curing of composite resin resulted in color changes of Premisa in red-blue direction and Denfil in green-blue direction. The DC and FS were affected by product, time and shade (3-way ANOVA, p < 0.05) and product and shade (2-way ANOVA, p < 0.05), respectively. Premisa only showed a significant correlation between the DC and CIE a* component - before and after polymerization (Pearson product moment correlation, p < 0.05). The FS of Premisa showed significant negative correlations with CIE a* and CIE b* components. CONCLUSIONS: The DC and FS of the light-curing composite resin were affected by the color components of the material before and after polymerization.
Subject(s)
Dental Enamel , Dentin , Polymerization , PolymersABSTRACT
OBJECTIVES: The purpose of this study was to determine whether pH and time has any influence on the degradation behavior of composite restoration by analyzing the leached monomers of dental composites qualitatively and quantitatively after storage in acetate buffer solution as a function of time using high performance liquid chromatography (HPLC) / mass spectrometer. MATERIALS AND METHODS: Three commercial composite restorative resin materials (Z-250, Heliomolar and Aeliteflo) with different matrix structure and filler composition were studied. Thirty specimens (7mm diameterx2mm thick) of each material were prepared. The cured materials were stored in acetate buffer solution at different pH (4, 7) for 1, 7 and 45days. As a reference, samples of unpolymerized composite materials of each product were treated with methanol (10 mg/ml). Identification of the various compounds was achieved by comparison of their mass spectra with those of reference compound, with literature data, and by their fragmentation patterns. Data were analysed statistically using ANOVA and Duncan's test. RESULTS: 1. Amounts of leached TEGDMA in Aeliteflo were significantly larger than those of UDMA in Z-250 and Heliomolar at experimental conditions of different storage time and pH variation (p 0.05).