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1.
The purpose of this study was to investigate the resistance to dissolution by two home-use fluoride gels on the surface integrity of glass-ionomer, resin modified glass-ionomer, compomer and composite resin restorations. Class V cavities prepared in extracted teeth were restored with a glass-ionomer (Fuji II), a resin modified glass-ionomer (Vitremenr), two compomers (Dyract and F-2000) and a composite resin (Z-100). Groups of five specimens of each material were treated for 24 h with one of the following: (i). distilled water, (ii). neutral fluoride gel and (iii). acidulated phosphate fluoride (APF) gel. Surface degradation of the restorations was studied using standard electron microscopy (SEM), rated according to specific criteria and statistically analysed by the Wilcoxon test (rank sums). Acidulated phosphate fluoride was found to have a significant effect on all examined materials, while minimal effects resulted from the neutral fluoride gel compared with the control group. The effect of home-use fluoride gels on glass-ionomer, compomer and composite resin restorations.  相似文献   

2.
The differences in polishability of modified and conventional glass-ionomers were studied following different polishing procedures. Specimens of conventional glass-ionomer (Fuji II(R)), resin modified glass-ionomer (Vitremer(R)) and compomer (Dyract(R)) were prepared and polished using either Soflex(R) or Enhance(R) discs with either aluminum oxide or poly(acrylic acid) gel as polishing agents. Surface roughness of the specimens was evaluated by profilometric measurements and electron microscopic examination. It was shown that Soflex(R) discs manifest superior polishing effect on glass-ionomers and resin modified glass-ionomers compared to the Enhance(R) system, although no significant differences were found for the compomer specimens. Addition of poly(acrylic acid) gel as a polishing agent reduced surface roughness of conventional glass-ionomer and resin modified glass-ionomer specimens and did not significantly affect the compomer specimens.  相似文献   

3.
The purpose of this study was to determine any inadvertent effects of the neodymium: yttrium-aluminium-garnet (Nd:YAG) laser, air-abrasion, and ortho-phosphoric acid on some conventionally used dental filling materials [amalgam, composite resin, compomer, glass-ionomer cement (GIC), and ceromer], when they were used for purposes of margin etching and assessed according to standard enamel etching parameters using a total of five fillings. The surfaces of the filling materials were polished. One sample from each material group was exposed to laser (at 0.75 J, 15 pps) and air abrasion (with Al-oxide powder, 60 psi) for 2 s and to the 37% ortho-phosphoric acid for 60 s. The exposed materials were examined under Scanning Electron Microscopy (SEM). After laser treatment most specimens showed recrystallized areas, the GIC surface being the most affected. There were some pores and cavities on the amalgam surface following laser treatment. The abraded surfaces showed mechanical abrasions. The acid etchant showed the least effect. During the application of laser or air-abrasion, the adjacent tooth or filling surface must be protected or the dentist must be careful.  相似文献   

4.
OBJECTIVE: Easy handling of materials is essential to the production of good clinical results. The handling properties of a new compomer material and its novel primer/adhesive-dispensing system were tested in clinical use. METHOD AND MATERIALS: Ten general dental practitioners used the new material and dispenser for 3 weeks and completed a questionnaire regarding the handling, esthetics, and ease of use. They were asked to compare the new material to the compomer, resin composite, and glass-ionomer materials normally used in their own practice. RESULTS: The material scored a mean of 4.4 for dispensing convenience on a linear scale of 1 (inconvenient) to 5 (convenient) and 4.6 for ease of use (5 = easy to use, and 1 = difficult to use). The dispensing system achieved a high rating of 4.9 for convenience (5 = convenient, and 1 = inconvenient). CONCLUSION: The new material received ratings that were superior to those of the glass-ionomer and compomer materials normally used by the evaluators and similar to ratings of the resin composite normally used.  相似文献   

5.
Shear bond strength of six restorative materials   总被引:1,自引:0,他引:1  
The purpose of this study was to determine and compare the shear bond strength of a conventional glass-ionomer cement, a resin modified glass-ionomer, a composite resin and three compomer restorative materials. Dentin of the occlusal surfaces from sixty extracted human permanent molars were prepared for shear bond strength testing. The specimens were randomly divided into six groups of 10 each. Dentinal surfaces were treated according to the instructions of manufacturers for each material. Each restorative material was placed inside nylon cylinders 2 mm high with an internal diameter of 3 mm, which were placed perpendicular to dentin surfaces. Shear bond strengths were determined using an Universal Testing Machine at crosshead speed of 0.5 mm/min in a compression mode. Conventional glass-ionomer, Ketac-Molar aplicap showed the lowest mean shear bond strength 3.77+/-1.76 (X +/- SD MPa) and the composite resin, Heliomolar showed the highest mean shear bond strength 16.54+/-1.65 while the mean bond strength of Fuji II LC was 9.55+/-1.06. The shear bond strengths of compomer restorative materials were 12.83+/-1.42, 10.64+/-1.42 and 11.19+/-1.19 for Compoglass, Hytac and Dyract respectively. ANOVA revealed statistically significant differences in the mean shear bond strengths of all groups (P<0.001). No statistically significant difference was found between the three compomer materials (P>0.5). Ketac-Molar and composite resin showed statistically significant difference (P<0.0005). The mode of fracture varied between materials. It is concluded that the compomer restorative materials show higher shear bond strength than conventional glass-ionomer and resin modified glass-ionomer, but less than composite resin. The fracture mode is not related to the shear bond strengths values.  相似文献   

6.
This study compared the amount and pattern of fluoride release from a new glass-ionomer-based material (nano-ionomer) with other restorative materials and correlated the surface area to volume of nano-sized filler with its capacity to release fluoride in the powder, more quickly increasing the fluoride. The materials evaluated were a nano-ionomer (Ketac N 100), a conventional glass-ionomer cement (GC Fuji II), a resin-modified glass ionomer cement (GC Fuji II LC), a compomer (Dyract F) and a fluoride-releasing resin composite (Tetric N Flow). A resin composite (Synergy Flow) served as the control. Ten specimens were fabricated from each of these materials using a customized metal mold. The fluoride release was measured every 24 hours for the first seven days, and on days 14, 21 and 28, a combination fluoride ion—selective electrode connected to an ion analyzer. The data was analyzed by one-way ANOVA and Tukey HSD test (p=0.05). An initial fluoride “burst effect” was seen with all of the materials, except for the control and compomer. The conventional glass-ionomer cement showed the highest fluoride release on the first three days. The nano-ionomer showed the maximum release of fluoride for the remaining days. A low constant level of fluoride release was seen from the compomer and fluoride-releasing resin composite throughout the study period.  相似文献   

7.
The effect of dental restorative materials on dental biofilm   总被引:6,自引:0,他引:6  
To investigate the arrangement of biofilms formed in vivo, volunteers wore splints with slabs of six different dental materials inserted to collect smooth surface plaque. After 5 d of undisturbed plaque accumulation, the specimens were vital stained and analyzed by the confocal laser scanning microscopy (CLSM) to evaluate the percentage of vital biofilm microflora (VF percentage). Further parameters were the area of the specimens covered by plaque (surface coating; SC, %) and the height of the biofilms (BH, pm). The metals amalgam and gold, the compomer, as well as the glass-ionomer cement harboured an almost entirely dead biofilm (VF <8%). Resin composite led to vitality values between 4 and 21%, while a very thin biofilm on ceramic revealed the highest vitality values (34-86%). SC varied from 6% on glass-ionomer cement to 100% on amalgam. BH reached its highest value on amalgam and gold of 17 and 11 microm, respectively, while heights of between 1 and 6 microm were found on the ceramic, resin composite, compomer and the glass-ionomer cement. Within their limits, the present findings indicate that amalgam, gold, compomer and glass-ionomer cement exert an influence against the adhering biofilm. No general relationship could be established between the different parameters VF percentage, SC percentage and BH (microm).  相似文献   

8.
OBJECTIVE: The objective of this study was to determine the cytocompatibility of 5 different extracts of resin-based restorative materials (2 resin-modified glass ionomer cements, 1 compomer, and 2 composite resins) on human pulp cells. STUDY DESIGN: Set specimens from 2 resin-modified glass-ionomer cements (Fuji II LC and Fuji IX), 1 compomer (Dyract), and 2 composite resins (Tetric and Superfil) were eluted with culture medium for 2 and 5 days. The effects of resin-based restorative materials on human pulp cells were evaluated with cytotoxicity and mitochondrial activity assays. RESULTS: The results showed that the eluates from resin-modified glass-ionomer, compomer, and composite resins were cytotoxic to primary human pulp cells. In addition, Superfil, Fuji IX, and Tetric demonstrated an inhibitory effect on mitochondrial activity of human pulp cells. It was found that composite resin Superfil was the most toxic restorative material among the chemicals tested. CONCLUSION: The influence of the cytotoxicity depended on the materials tested. Compomer or light-curing resin-modified glass ionomer may initially react more favorably to pulp cells.  相似文献   

9.
The objectives of this investigation were (1) to develop a sensitive laboratory system that simulates the physiological and clinical conditions of a prepared human tooth in order to facilitate the determination of the bonding and sealing efficacies of restorative dental materials and (2) to conduct experiments with two dentin bonding agents, two posterior composite resin restorative materials (hybrid and microfilled), and a glass-ionomer type II filling material. The system functioned well and provided data to indicate that, after margination, the two posterior composite resin restorative materials performed equally and both performed better than the glass-ionomer filling material; none of the materials provided a perfect seal immediately after insertion, although some restorations demonstrated perfect seals from 16 hours to 28 days after placement; the seal of the glass-ionomer material improved after 28 days of storage in buffer solution; each successive step in the respective composite resin procedures improved the seal except in one case for the microfilled resin.  相似文献   

10.
Yu H  Li Q  Attin T  Wang Y 《Operative dentistry》2010,35(6):634-640
This in vitro study evaluated the effects of a resin coating on the microleakage of Class V restorations due to bleaching. One-hundred and sixty Class V cavities were randomly restored with one of four different restorative materials (n = 40): a compomer (Dyract AP), a conventional glass-ionomer cement (Ketac Molar Easymix), a resin modified glass-ionomer cement (Fuji II LC) and a resin composite (Filtek Z350). For each kind of material, 40 restorations were divided into four subgroups: bleached with resin coating (group BC), bleached without resin coating (group B), immersed in artificial saliva with resin coating (group SC), immersed in artificial saliva without resin coating (group S). In groups B and BC, the specimens were bleached with 10% carbamide peroxide gel for eight hours daily, while groups SC and S were stored in artificial saliva instead. After 28-day treatment, all the samples were subjected to a dye penetration test using the multiple-sectioning technique. In addition, one more test was performed to investigate the color difference between the coated and uncoated tooth surface after bleaching. There was a statistically significant increase in cervical microleakage in the group B specimens of Fuji II LC and Ketac Molar Easymix compared to their respective control specimen (group S). These effects on microleakage were not found in the bleached specimens with resin coating (group BC). There was also no visually-detectable color difference between the coated and uncoated tooth surface. In conclusion, resin coating is an effective method for avoiding the bleaching-induced microleakage of glass-ionomer cement.  相似文献   

11.
The present study was carried out to compare the marginal microleakage of some newer materials viz. a flowable composite, an injectable resin modified glass-ionomer and a compomer in Class I cavities of 30 non carious primary molars. After 0.5% basic fuchsin dye penetration and sectioning, the teeth were studied under stereomicroscope. The results obtained revealed that flowable composite showed significantly lower microleakage (p<0.05) as compared to injectable resin-modified glass ionomer and compomer. However, no significant difference was observed when injectable resin modified glass-ionomer cement was compared to compomer. This concludes that flowable composite materials adhere better to the primary teeth than resin modified glass ionomer and compomer.  相似文献   

12.
Yu H  Li Q  Hussain M  Wang Y 《Journal of dentistry》2008,36(4):261-267
OBJECTIVES: The purpose of this study was to evaluate the effects of a home bleaching gel containing 15% carbamide peroxide on the surface microhardness of four tooth-colored restorative materials in situ. METHODS: Four types of tooth-colored restorative materials, including a nanocomposite resin (Filtek Z350), a packable composite resin (Filtek P60), a polyacid-modified composite (Dyract AP), and a glass-ionomer cement (Ketac Molar Easymix), were used in this study. Each material was divided into two groups equally (n=18): bleaching group and control group. Thirty-six Chinese volunteers were recruited and stone casts were constructed for their upper jaws. Two of the four types of restorative materials were randomly selected and mounted on the first or second molar of the cast for each subject. With respect to each material selected, two specimens from each group were put at a random side. Then custom-fabricated trays containing specimens were fabricated. The participants wore the tray in the daytime, and applied the bleaching gel for the side containing specimens of bleaching group during the night. Surface microhardness measurements were obtained on the top surface of each sample on the different time periods. RESULTS: There was a statistically significant increase in the surface microhardness of Ketac Molar Easymix due to the exposure to 15% carbamide peroxide, while it produced a significant decrease for Dyract AP. Following immersing in saliva without bleaching agent, Ketac Molar Easymix showed a significant increase in surface microhardness. CONCLUSIONS: The effects of 15% carbamide peroxide on surface microhardness were material dependent. Immersing in saliva produced a surface hardening effect of glass-ionomer cement.  相似文献   

13.
The effect of 3 percent, 11 percent, and 16 percent carbamide peroxide bleaching solutions and 35 percent hydrogen peroxide bleaching gel on microleakage of Class V composite resins, resin modified glass ionomer cements, and compomer restorative materials together with corresponding (if indicated) fourth/fifth generation bonding agents was evaluated using previously extracted human teeth. Five groups of Class V cavity preparations were placed in enamel of the facial surfaces of 200 teeth. Groups A through D included 40 restorations each (4 different restorative materials and their accompanying bonding agent multiplied by 10 teeth) treated with 3 percent, 11 percent, and 16 percent carbamide peroxide bleach and 35 percent hydrogen peroxide bleach. Group E included 40 restorations without treatment of bleach and stood as the control. The restorative materials included were: Fuji II LC resin modified glass ionomer cement, Helioprogress composite resin/-Heliobond adhesive system, Aelitefil composite resin/Allbond 2 adhesive and Dyract compomer material/Prime & Bond adhesive system. Bleaching agents included were Rembrandt 3 percent peroxide gel, Perfecta 16 percent carbamide peroxide gel, White & Brite 11 percent carbamide peroxide solution and Superoxyl 35 percent hydrogen peroxide gel. All teeth were thermally stressed for 100 cycles and microleakage were assessed by dye penetration. The results were tabulated using Analysis of Variance (ANOVA) testing procedures. The Aelitefil composite resin material behaved the least favorably (relative to microleakage) compared to the other materials when exposed to various concentrations of dental bleaching agents.  相似文献   

14.
This study determined the effect of pH on the surface texture of commonly used posterior glass-ionomer based/containing restorative materials. The materials evaluated included a compomer (Dyract AP), a giomer (Beautifil) and two highly viscous glass ionomer cements (Fuji IX and Ketac Molar). A resin composite (Esthet-X) was used for comparison. Forty-two specimens (3-mm wide x 3-mm long x 2-mm deep) were made for each material. The specimens were divided into six groups and conditioned in the following solutions at 37 degrees C for one week: Citric acid (pH 2, 3, 4, 5 and 6) and distilled water (pH 7). After conditioning, the surface roughness (Ra, microm) of each specimen was measured using a surface profilometer (Surftest, Mitutoyo Corp, Tokyo, Japan). Data was analyzed using one-way ANOVA and Scheffe's test at a significance level of 0.05. The effects of pH on the surface texture of glass-ionomer based/containing restoratives were material dependent. Ra values ranged from 0.02 microm to 0.15 microm and 0.03 microm to 4.40 microm for pH 7 and 2, respectively. With the exception of the composite, the surface roughness of all materials evaluated was significantly affected by acids of low pH. The surface texture of highly viscous glass ionomer cements deteriorated significantly when conditioned in solutions of low pH, which makes them more susceptible to clinical failure.  相似文献   

15.
OBJECTIVE: The aim of this in vitro study was to evaluate the tensile bond strength values between polyacid-modified resin composite ("compomer") and resin composite materials under different conditions. METHOD AND MATERIALS: There were five experimental groups in the study. In group A, resin composite was placed directly on polyacid-modified resin composite surfaces. In group B, bonding agent was applied to polyacid-modified resin composite surfaces and then resin composite was placed on the compomer. In group C, compomer specimens were stored for 1 week and then resin composite was placed directly on these aged compomers. In group D, compomer specimens were again stored for 1 week, and then the bonding agent and resin composite were applied to the compomer surfaces. In group E, the surfaces of aged (1 week) compomers were roughened before the bonding agent was applied and the resin composite was placed on the prepared surfaces. A statistical analysis of the results was made with the Kruskal-Wallis test method. RESULTS: The mean tensile strength values of the groups were as follows: group A = 12.84 MPa; group B = 15.03 MPa; group C = 10.60 MPa; group D = 11.56 MPa; group E = 24.87 MPa. There were statistically significant differences between groups E and A; groups E and C; groups E and D; and groups C and B. CONCLUSION: Mechanical roughening of a polyacid-modified resin composite surface was found to be the most effective factor in increasing the tensile bond strength between an aged compomer and a resin composite.  相似文献   

16.
PURPOSE: To evaluate (1) the wear rates of various types of luting materials by means of toothbrush and generalized wear tests, and (2) the relationship between interfacial gap and luting material wear. METHODS: NiCr inlays were cemented into cylindrical Class I cavities prepared on flattened extracted molars with various luting materials (composite, compomer, hybrid and conventional glass-ionomers, and zinc phosphate). They were stored in 37 degrees C water for 24 hours and then resurfaced with a 600 grit Si-C paper. Half the specimens were subjected to 100 minutes of toothbrushing with a 1.47 N load using an automated brushing device, and the rest of the specimens were subjected to three-body generalized wear test with a 75 N load and 1.2 Hertz for 133,333 cycles. Eight specimens were evaluated for each cement by both wear modes. Wear depths of the luting materials were measured with a profilometer. The data were statistically analyzed by two-way ANOVA, and differences between wear modes and among luting materials were analyzed by a Bonferroni test (P< 0.05). RESULTS: There were significant differences between the luting materials (P< 0.0001) and wear mode (P= 0.015) for wear depth but no significant interaction between luting material and wear mode (P= 0.1059). The wear values of the resin-based composite (6.4 +/- 3.1 microm) and compomer (6.2 +/- 2.4 microm) were significantly lower than those of the hybrid glass-ionomer (11.3 +/- 2.8 microm), the conventional glass-ionomer (11.1 +/- 4.4 microm), and the zinc phosphate (12.1 micro 1.7 microm) in the toothbrush wear. The wear value of the resin-based composite (6.5 +/- 3.1 microm) was significantly lower (P< 0.0001) than those of zinc phosphate (15.0 +/- 2.7 microm) and hybrid glass-ionomer (13.5 +/- 1.5 microm), but not significantly different from conventional glass-ionomer (10.1 +/- 3.9 microm) and compomer (10.2 +/- 2.5 microm) in the generalized wear.  相似文献   

17.
目的:研究Carisolv去龋对牙本质粘结界面的影响。方法:24颗新鲜拔除的中度龋损的第三磨牙,随机分成ABCD4组。每个牙的龋洞分成两半,一半用Carisolv去龋,另一半用涡轮车针去龋后,做如下处理:A组不处理;B组320ml/L磷酸酸蚀,扫描电镜观察牙本质表面形态;C组不酸蚀,DyractAP复合体充填;D组320ml/L磷酸酸蚀后复合树脂充填,扫描电镜观察牙本质-充填体界面。结果:A组:Carisolv去龋后牙本质表面玷污层少,大部分牙本质小管口开放,清晰可见,表面粗糙不平;涡轮车针去龋后牙本质表面覆盖较厚玷污层,牙本质小管口堵塞,很少见到开口。B组:Carisolv去龋组和涡轮车针去龋组均去除了玷污层,牙本质小管口开放,但Carisolv组牙本质小管无管塞,而涡轮车针组牙本质小管残留部分管塞。C组:观察牙本质-复合体界面见Carisolv去龋组有较多树脂突形成,深入牙本质小管及管周;而涡轮车针去龋组未见明显树脂突起形成。D组:观察牙本质-树脂界面见2组树脂突的密度和长度无明显差异,但Carisolv去龋组树脂突之间的侧枝连接较涡轮车针去龋组多见。结论:Carisolv去龋后牙本质表面玷污层少,牙本质小管口开放,表面粗糙不规则,利于粘结,尤其在使用不需酸蚀的复合体充填时优势突出。  相似文献   

18.
Yap AU  Mok BY 《Operative dentistry》2002,27(6):576-581
This study investigated the effects of professionally applied topical fluorides on the surface hardness of a composite (Spectrum TPH), a compomer (DyractAP) and a giomer (Reactmer). Thirty specimens of each material were fabricated and stored in distilled water at 37 degrees C for one week. These specimens were then randomly divided into five groups of six and treated for 36 hours at 37 degrees C with one of the following: distilled water (control), 1.23% acidulated phosphate fluoride (APF) foam, 0.9% neutral foam, 1.23% APF gel and 0.4% stannous fluoride gel. The treated specimens were subsequently subjected to microhardness testing (load = 500 gf; dwell time = 15 seconds). Results were analyzed using ANOVA/Scheffe's test (p<0.05). The effects of topical fluoride application on surface hardness was material dependent. For all materials, treatment with APF gel and foam significantly reduced surface hardness when compared to the control. KHN values after exposure to APF gel were consistently the lowest and ranged from 4.53 to 15.97. Control KHN values were higher, ranging from 32.88 to 47.47. The surface hardness of the compomer was also significantly reduced after exposure to neutral foam. Therefore, the use of professionally applied topical fluorides, especially APF gel and foam, may be detrimental to the long-term durability of composite-based restoratives.  相似文献   

19.
Currently available glass-ionomer, resin-modified glass-ionomer, and compomer materials have relatively low strength and toughness and, therefore, are inadequate for use in large stress-bearing posterior restorations. In the present study, ceramic single-crystalline whiskers were mixed with fluorosilicate glass particles and used as fillers to reinforce experimental carboxylic acid-resin composites. The carboxylic acid was a monofunctional methacryloxyethyl phthalate (MEP). Five mass fractions of whisker/(whisker + fluorosilicate glass), and corresponding resin (resin + MEP), were evaluated. Four control materials were also tested for comparison: a glass ionomer, a resin-modified glass ionomer, a compomer, and a hybrid composite resin. Flexural specimens were fabricated to measure the flexural strength, elastic modulus, and work-of-fracture (an indication of toughness). Fluoride release was measured by using a fluoride ion selective electrode. The properties of whisker composites depended on the whisker/(whisker + fluorosilicate glass) mass fraction. At a mass fraction of 0.8, the whisker composite had a flexural strength in MPa (mean +/- sd; n = 6) of 150 +/- 16, significantly higher than that of a glass ionomer (15 +/- 7) or a compomer control (89 +/- 18) (Tukey's multiple comparison test; family confidence coefficient = 0.95). Depending on the ratio of whisker:fluorosilicate glass, the whisker composites had a cumulative fluoride release up to 60% of that of a traditional glass ionomer. To conclude, combining ceramic whiskers and fluorosilicate glass in a carboxylic acid-resin matrix can result in fluoride-releasing composites with significantly improved mechanical properties.  相似文献   

20.
The aim of this study was to compare the in vitro caries inhibition of various resin-based materials. Class V cavities were prepared in twenty-five freshly extracted human premolar teeth which were then restored with glass-ionomer cement (Chemfill II), compomer (Compoglass F, Dyract AP) and composite resin (Tetric Ceram and Z 100). The teeth were submerged in an acid gel for 6 weeks. Each specimen was sectioned. These sections were left in water for 24 hours, and then examined using polarized light microscopy. The lesion consisted of two parts, the outer surface lesion and the cavity wall lesion. There was no significant difference in the body depth of the outer lesion and in the depth of the wall lesion among teeth restored with Compoglass F, Dyract AP and Chemfill II (P > 0.05). There was a significant difference between those restored with Z 100 and Tetric Ceram (P < 0.05). The length of the wall lesion for the teeth restored with Chemfill II was significantly smaller than that in the remaining groups (P < 0.05). The length of the wall lesion for teeth restored with Tetric Ceram and Z 100 was significantly higher than in the remaining groups (P < 0.05). These results suggest that composite materials and compomer provide less caries inhibition than glass-ionomer cements.  相似文献   

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