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1.
OBJECTIVES: Until recently, esthetic inlay restorations in posterior teeth have been limited to cavities surrounded by enamel. Dentin adhesive systems in combination with luting composites and light-cured resin-modified glass ionomer cements offer a possibility for bonding ceramic inlays to cavities when the cervical margin is in dentin. This study was designed to compare in vitro marginal integrity of ceramic inlays bonded to dentin to restorations placed in cavities with margins located entirely in the enamel. METHODS: In the present in vitro study, the sealing abilities of a dentin bonding agent/luting composite combination (Syntac/Dual Cement, Vivadent) and resin-modified glass ionomers (Photac Fil, Photac Bond, ESPE; Dyract, De Trey Dentsply; Fuji II LC, GC Dental Industrial Corp.; and Vitremer, 3M Dental Products) used as luting agents in cavities extending beyond the cemento-enamel junction, were compared to the sealing abilities of a conventional luting composite (Vita Cerec Duo Cement, Vita) in cavities within sound enamel. SEM analysis and dye penetration were performed to evaluate marginal integrity at the cervical cavity margins. RESULTS: The dentin bonding agent/luting composite combination (Syntac/Dual Cement) rendered a marginal seal within the dentin similar to the quality obtained with the conventional luting procedures within sound enamel. When three out of the five resin-modified glass ionomers were used as luting agents (Dyract, Fuji II LC and Vitremer), the results were comparable to those reported for the dentin bonding agents and the conventional method. SIGNIFICANCE: Light-cured resin-modified glass ionomer cements may be considered as an alternative to dentin bonding agents when the cavity margins of ceramic inlay restorations are within the dentin. However, further studies, e.g., wear resistance, must be performed.  相似文献   

2.
PURPOSE: To evaluate the 2-year clinical performance of two polyacid-modified resin composites and two resin-modified glass ionomers in Class V carious cavities. MATERIALS AND METHODS: A total of 120 Class V cavities were selected and 30 cavities were restored with one of two resin-modified glass ionomer materials (Fuji II LC Improved and Vitremer) and two polyacid-modified resin composites (Dyract and Compoglass) in Class V carious cavities after 2 years. The restorations were clinically evaluated after 1 and 2 years using the USPHS criteria. RESULTS: One-year findings revealed a significant difference in color match between Vitremer and other materials (P < 0.05) and no significant difference was found for the other criteria. Two-year results indicated a significant difference between resin-modified glass ionomers and polyacid-modified resin composite materials. The difference between Compoglass and Dyract was not statistically significant whereas the difference between Vitremer and Fuji II LC was statistically significant. Caries was not recorded at any evaluation period.  相似文献   

3.
Recently, new restoratives, such as resin-modified glass ionomer cements (RMGIC) and polyacid-modified resin composites (PMC) were introduced for class III and class V cavities. Both materials use simplified cavity conditioning methods. The well-established treatment of enamel with phosphoric acid has been replaced with treatment using weaker acids. The purpose of this study was to investigate in vivo the quality and durability of the marginal bond to enamel of these restorative system and compare it with a resin composite restorative, Seventeen patients received class III restorations of each of the three restoratives. At baseline and after 1 year replica impressions were made for investigation of the vestibular margins with the scanning electron microscope. Semi-quantitative analysis of the enamel-restorative interfaces was performed at x200 and x1000 magnifications. The three restorative systems showed good marginal adaptation and high percentages of the length of the margins investigated at baseline were gap-free (82%-92%). The resin composite showed significantly better adaptation than the other materials. The marginal quality decreased significantly after 1 year for the resin composite and the polyacid-modified resin composite. The RMGIC showed improved sealing after 1 year in vivo, probably due to continuing water uptake. The percentages of gap-free margins of the total marginal length observed at 1 year were 73%, 90%, and 84%, respectively, for the PMC, the RMGIC and the resin composite. The difference between the PMC and the RMGIC was significant. In conclusion, a good marginal quality was seen for all three restorative systems in class III cavities after a period of 1 year.  相似文献   

4.
PURPOSE: To compare the shear bond strengths to dentin of four tooth-colored fluoride-releasing restorative materials that utilize different mechanisms of dentin-bonding. MATERIALS AND METHODS: Four materials were tested: a chemically-cured glass ionomer (Ketac-Fil); a light-cured resin-modified glass ionomer (Photac-Fil); a light-cured resin-modified glass ionomer in conjunction with a resin dentin-bonding agent (Vitremer); and a light-cured resin composite in conjunction with a resin dentin-bonding agent (Tetric). The enamel was removed from four sides of the twenty human noncarious extracted molars which had their roots embedded in acrylic blocks. Cylindrical samples of the materials were prepared in plastic molds and bonded to the dentin surface according to the manufacturers' instructions. After 24 hours of storage in a humidor, the samples were sheared with an Instron testing machine at a crosshead speed of 0.5 mm/minute. RESULTS: Statistical evaluation (ANOVA and Duncan's test) suggests that the fluoride-releasing resin composite material utilizing a resin dentin-bonding agent provided a significantly greater mean shear bond strength (16.5 MPa) after 24 hours storage than any of the selected glass ionomer materials. Of the three glass ionomer materials compared, the light-cured resin-modified material with a resin dentin-bonding agent provided a significantly greater mean shear bond strength (6.7 MPa) than the light-cured resin-modified material without a resin dentin-bonding agent (3.0 MPa) or the chemically-cured material (3.8 MPa).  相似文献   

5.
The tooth interface with resin-modified glass-ionomer cements (RM GICs) is poorly understood. This study examined the interface, especially with dentin. Cervical cavities in extracted teeth were restored with Fuji II LC, Vitremer, Photac-Fil, or a conventional GIC, Fuji Cap II. Fluorescent dye was placed in the pulp chambers for 3 hrs before the specimens were sectioned. Examination of the tooth/material interface with a confocal microscope showed that dye uptake by the restoration varied among materials. A "structureless", non-particulate, highly-stained layer of GIC was observed next to dentin in Fuji II LC. This layer varied in width, was prominent where the dentin tubules were cut "end-on" and in areas closer to the pulp, and was not seen adjacent to enamel. Vitremer showed minimal dye uptake, and the "structureless" layer was barely discernible. Photac-Fil showed more uniform uptake and absence of this layer. Cracking of enamel was also noted with these materials. The conventional GIC did not show any dye uptake, presence of a "structureless" layer, or enamel cracking. We elucidated the potential mechanisms involved in the formation of a "structureless" interfacial layer in Fuji II LC by studying the variables of cavity design, surface pre-treatment, water content of the tooth, time for it to develop, early finishing, and coating of the restoration. This layer, the "absorption layer", is probably related to water flux within the maturing cement, depending on environmental moisture changes and communication with the pulp in a wet tooth. The "micropermeability model" was useful in this study of the interfacial characteristics of RM GICs.  相似文献   

6.
The objective of this study was to evaluate the initial tensile bond strength of a resin-modified glass ionomer (Photac-Fil) and two polyacid-modified composite resins (Compoglass, Dyract) to primary dentin. A hybrid composite resin (Tetric) and two chemical cured glass ionomers (BaseLine, Hi-Dense) served as controls. Ninety caries-free dentinal discs were ground flat and perfused with Ringer's solution. Dentinal surfaces were conditioned (except for Base Line). From each material, fifteen standardized specimens were attached to the dentin. Light-curing of the respective materials followed (1 min), and adhesion was tested with a universal testing machine 15 min after application. The highest initial bond strength was observed with Tetric (5.17 MPa). Closed test procedure (Kruskal-Wallis) showed significant differences between all materials (P < 0.05), except for Compoglass (1.82 MPa) vs. Dyract (2.35 MPa), and BaseLine (0.37 MPa) vs. Photac-Fil (0.42 MPa). The condensable glass ionomer Hi-Dense revealed a mean tensile bond strength of 0.79 MPa. Adhesion of (polyacid-modified) composite resins is superior to the other tested glass ionomer materials, when applied to perfused primary dentin.  相似文献   

7.
The objective of this study was to evaluate the effects of glass-ceramic inserts on reducing the marginal gaps caused by polymerization shrinkage in composite restorations. A light microscope was used to measure the largest gap at margins around restorations made in glass cylinders and tooth cavities with and without adhesion promoters. Where the cylinder was not silanated, the average gap was less in samples containing an insert than in those without. Two preparations were made in the dentin of 20 human molars. In each molar one cavity was restored with a dentin bonding agent and composite and the other with a dentin bonding agent and an insert seated in the composite. The average maximum gap width of restorations containing inserts was statistically less than for those with only composite (paired t-test, P<0.0001). When considering the volume of composite displaced by the insert, these results that the use of a glass-ceramic insert decreased the marginal gaps resulting form polymerization shrinkage.  相似文献   

8.
The purpose of this study was to investigate the effect of dentinal disinfection with a 2% chlorhexidine or a 0.11% I2-KI/CuSO4 solution on the shear bond strength of three resin-modified glass-ionomer cements: Fuji II LC, Photac-Fil, and Vitremer. The occlusal surfaces of extracted human teeth were flattened to dentin. Specimens were randomly assigned to one of nine treatment groups (n = 12). For each glass-ionomer material, there was a control group and two treatment groups in which the dentin was treated with either a 2% chlorhexidine or a 0.11% I2-KI/CuSO4 solution before the dentin was treated with the recommended dentin conditioner prior to glass-ionomer bonding. Specimens were stored for 1 day in water, thermocycled, and tested in shear until failure. The chlorhexidine solution did not significantly affect the shear bond strengths of any of the cements, but the I2-KI/CuSO4 solution significantly lowered the bond strengths of Vitremer and Fuji II LC compared to the controls.  相似文献   

9.
PURPOSE: To evaluate a dental adhesive system that uses a single conditioning/primer agent. MATERIALS AND METHODS: Twenty-five flat enamel and dentin bonding sites were prepared to 600 grit on human molar teeth. The Clearfil Liner Bond 2 adhesive system was used to bond Clearfil AP-X composite to both enamel and dentin. After 24 hours of water storage, shear bond strengths were determined using an Instron testing machine. Fifty V-shaped cavity preparations were prepared in human molar teeth with an enamel and cementum margin. Composite restorations were placed using the new adhesive system. The teeth were stored for 24 hours, thermocycled, stained with AgNO3 , sectioned and examined for microleakage. SEM examinations were also completed to evaluate the effects of the treatment steps on enamel and dentin surfaces. RESULTS: Mean shear bond strengths for the experimental adhesive to enamel and dentin were 28.2 +/- 4.9 and 19.4 +/- 3.1 MPa. A t-test revealed that the enamel bond strength was significantly greater (P<0.05) than the dentin strength. No marginal leakage was observed from the enamel margins of the restorations. Three restorations showed minimal leakage from the cementum margins. SEM examinations showed resin penetration into both the conditioned enamel and dentin surfaces. The adhesive system produced high bond strengths to both enamel and dentin, exhibited very minimal microleakage and was easy to use.  相似文献   

10.
OBJECTIVES: The pulpal reaction and the marginal sealing of in vivo restored samples using resin composite and Scotchbond Multi-Purpose adhesive system (3M Dental Products) were analyzed in this study. METHODS: Twelve Class I non-exposed cavity preparations were placed on premolars to be removed for orthodontic reasons. They were restored and observed at 7 d and 28 d. RESULTS: The examination of the resin-dentin interface under the scanning electron microscope (SEM) revealed: 1) a gap-free attachment between adhesive resin and dentinal surface in 80% of the areas studied, 2) penetration of resin tags into the dentinal tubules, and 3) formation of a 3-5 micrometer thick acid-resistant hybrid layer. Microfissures measuring about 10 micrometers were observed in only 20a% of the areas studied; these were located along the walls of the cavities, especially near the enamel in zones where there was a lower concentration of dentinal tubules. The histological analysis, carried out 7 d after preparation of the restoration, did not show any alteration of the pulp. After 4 wk, reparative dentin was produced in the pulpal areas corresponding to the restored cavities. SIGNIFICANCE: The quantity of newly formed dentin is correlated with the distance from the cavity to the pulp. The results indicate that acid-etching of vital dentin using 10% maleic acid does not impair pulpal healing in deep Class I cavities and that the Scotchbond Multi-Purpose adhesive system is able to preserve the morphological and biological integrity of the pulpo-dentinal complex.  相似文献   

11.
PURPOSE: To evaluate in vitro the cervical gap formation in composite restorations in which an increment of autopolymerizing composite was interposed between the light-cured filling material and the dentin bonding system. Two different self-cured materials and two different adhesives were used and compared. MATERIALS AND METHODS: In 40 Class II cavity preparations with the gingival margins in dentin or cementum, an increment of either of two different autopolymerizing composites, Palfique or Bisfil 2B, was interposed between the light-cured filling material (Palfique Estelite) and either of two different dentin bonding systems, All-Bond and Superbond D (20 restorations each). The specimens were immersed in toluidine blue dye. A section was taken from each specimen and examined under an optical microscope. The extent of dye penetration was measured. The specimens were then stored in water for 1-4 months and replicas of the sections were examined by SEM. RESULTS: Good marginal adaptation was observed for All-Bond/Bisfil 2B in all the restorations. All-Bond/Palfique showed good adaptation in 7 out of 10 cases, the failures occurring between bonding agent and composite. Superbond D/Palfique and Superbond D/Bisfil 2B showed marginal gap formation in 8 out of 10 and in all the restorations respectively. In the latter, four gaps occurred between bonding agent and dentin. As a consequence, a very significant difference (P<0.001) was found between All-Bond and Superbond treatments; no significant difference was found between Bisfil 2B and Palfique in each group treated with either All-Bond or Superbond. After 1-4 months storage in water, hygroscopic expansion of the restorative materials reduced the total number of gaps and the efficacy of the treatments was no more significantly different.  相似文献   

12.
The present study investigates the effect of storage in water on hygroscopic expansion and shear bond strength to dentin at periods up to 1 week, of the resin-modified glass ionomers for base/liner, and to analyze the effect on the marginal gaps in dentin cavities. For polishing after storage in water for 1 day, the material indicated significantly smaller marginal gaps both in dentin and in Teflon cavities than in those immediately after light-activation. For the results of after storage in water for 1 day, the material indicated significantly greater bond strength than material immediately after light-activation. The improvement of marginal sealability in dentin cavities may be performed not only by hygroscopic expansion during storage in water but also by greater bond strength after the setting reaction which continues to advance during storage in water.  相似文献   

13.
OBJECTIVES: Recurrent caries is one of the most common reasons for the replacement of restorations. One method of reducing the frequency of this problem may be by using fluoride-releasing restorative materials. The aim of this in vitro study was to evaluate the progression of artificial lesions around resin-modified glass ionomer (Vitremer) restorations placed in root surfaces. Class V cavities were prepared on the mesial and distal surfaces of 28 human premolar teeth. Artificial carious wall lesions were created in all cavities. The root of each tooth was then hemisected through the middle of the two cavities, before being restored with either the glass ionomer or amalgam, while the opposing cavities on the same root portion were varnished as negative controls. Forty-eight specimens were pH-cycled in remineralising and demineralising solutions for 20 h and 4 h, respectively, each day for 4 weeks, whilst in a smaller control group of eight specimens, the demineralising solution was replaced with deionised water. Mineral changes in the carious lesions were evaluated using contact microradiography. RESULTS: Results showed that varying degrees of subsurface demineralisation and remineralisation were evident, with a laminated appearance in lesions adjacent to the glass ionomer. There was higher remineralisation in the glass ionomer-filled cavities compared with the amalgam-filled cavities. In the water-cycled group, glass ionomer showed an increase in mineral content (p < 0.05), while no changes were observed in the amalgam-filled cavities. CONCLUSIONS: This model has shown that glass ionomer has a greater potential than amalgam for remineralisation of artificially created wall lesions within an acidic environment.  相似文献   

14.
PURPOSE: The purpose of this study was to determine the in vitro effects of a resin-modified glass-ionomer restorative material on human enamel. METHODS: Enamel specimens were restored with Photac-Fil, a resin-modified glass ionomer; Ketac-Fil, an autopolymerizing glass ionomer and silver amalgam. The samples were pH cycled and then subjected to an artificial caries challenge. Specimens were evaluated by fluoride microdrill biopsy and quantitative microradiography at 1, 2, and 3 mm from restorations. Data on fluoride content, lesion depth, and mineral content were analyzed by one-way ANOVA, Student's t test, Neuman-Keuls procedure (multiple [pairwise] comparison), and Pearson's product-moment correlation tests. RESULTS: There were significant differences in fluoride uptake, lesion depth, and mineral density between groups. Significant correlational relationships were also determined. CONCLUSION: This study demonstrates that Photac-Fil and Ketac-Fil prevent in-vitro demineralization of enamel and suggests different mechanisms of action for each material.  相似文献   

15.
The aim of this in vitro trial was to evaluate the external and internal adaptation of class II composite restorations to tooth structure by means of replica scanning electron microscope (SEM) observation. Standard MOD preparations were cut in human extracted teeth with margins located above and below the cementoenamel junction. Cavities were restored with either a direct multilayered technique, inlays (using conventional or dual DBA application) or prepolymerized composite inserts, using similar restorative material (Syntac, Variolink and Tetric). Evaluations were performed after mechanical and thermocycling. For the marginal adaptation in enamel, the bevelled margins of the direct group resulted in higher percentages of "continuity" (92.5% mesially and 94.6% distally), while the "marginal tooth fracture" was the most commonly found defect in groups with a butt preparation (up to 29.4%, with inserts). For the marginal adaptation in dentin, "continuity" percentages varied from 59% (inlay) to 87.9% (insert). As regards the internal adaptation, results for the whole dentin interface varied from 43.1% (inlay) to 63.9% (inlay with dual bonding) of "continuity". No regional difference in internal adaptation was found between the different preparation areas, except between gingival dentin and gingival enamel (44.9% vs. 80.7% of continuity, all group pooled data). Debonding occurred only at the dentin-restoration interface and consistently took place at the top of the hybrid layer. In the present experimental conditions, the inlay or insert techniques, which make use of the Dual bonding concept, proved to have the best potential to maintain the integrity of dentin-restoration interface.  相似文献   

16.
PURPOSE: To investigate the effects of acetone or water based Gluma primers on bonding efficacy when applied to acid-etched wet, dry or rewetted dentin. MATERIALS AND METHODS: Shear bond strength (SBS, 24 hours) was measured on human dentin etched with 20% phosphoric acid gel and rinsed with water in the wet (blot dried), the conventional (2 seconds air blast), the dry (10 seconds air drying), and the rewetted stage (10 seconds air drying, remoistening and blot drying). The priming solution was either the original water based or an acetone based experimental Gluma primer. Cavity sealing performance and depth of resin impregnation were determined by solvent and by technique along the margins of 4.5 mm wide cylindrical dentin cavities with 90 degree cavosurface angle. RESULTS: The SBSs of the wet technique groups were approximately 18 MPa, irrespective of the primer solvent. Conventional drying gave an SBS almost as high (16.5 MPa). Rewetting was highly effective with acetone as the primer solvent. The dry techniques resulted in moderate (water) and poor (acetone) bond strengths. The cavity margins of acetone based primer treated specimens were consistently gap free with the wet technique. The other seven groups showed between two and six gaps in each group of six specimens. The resin impregnated layer (RIL) thicknesses were 12.5 microns approximately in the wet groups, and thus identical with the total depth of demineralization resulting from the 30-second etching. The alternative techniques showed significantly thinner RILs particularly in the dry groups (7.5 microns).  相似文献   

17.
Modern dental adhesive systems have improved the bond of restorative materials to mineralized tooth structures. The purpose of this study was to evaluate the clinical performance of composite restorations placed in abrasion and erosion lesions using the Clearfil Liner Bond dental adhesive system. Following ADA clinical guidelines for dentin and enamel adhesive materials, 62 facial class 5 smooth surface erosion or abrasion lesions with no undercuts and involving primarily root surfaces were restored in 25 adult male and female patients. The teeth were restored without preparations using Clearfil Liner Bond and Clearfil Photo Anterior composite resin. The clinical performance of the restorations was assessed by two examiners at baseline, 6 months, 1, 2, and 3 years using the following evaluative parameters: color match, marginal discoloration, and marginal integrity according to modified Ryge criteria; the presence or absence of recurrent decay; pre- and postoperative sensitivity; and restoration failure due to loss of retention or other causes. At the end of 3 years, four of the 55 restorations remaining in the study failed due to lack of retention (92.7% retention rate). The evaluations of the other clinical parameters demonstrated excellent performance by this system.  相似文献   

18.
PURPOSE: To measure and compare the microleakage of Class V resin composite restorations using the following three pairs of multi- and simplified-step dentin bonding systems (DBS): OptiBond vs. OptiBond FL, All-Bond 2 vs. One-Step, and Tenure vs. Tenure Quik. MATERIALS AND METHODS: V-shaped cavities were prepared in the mesial and distal surfaces of 30 extracted human mandibular molars with margins in both enamel and cementum, and randomly assigned into three equal groups of 10 each. All DBSs were applied strictly following manufacturers' specifications before three incremental layers of resin composite (Pertac-Hybrid) were applied in all cavities. Specimens were stored for 7 days in 37 degrees C water, thermocycled for 300 cycles between 5 degrees C and 55 degrees C, immersed in 0.5% basic fuchsin solution for 24 hours, and embedded in resin before being sectioned longitudinally in multiple sections. Dye solution penetration at the tooth/composite interface was scored from 0 to 4 under a microscope at x100 at both enamel (E) and cementum (C) margins. Data were analyzed by Kruskal-Wallis and Mann-Whitney U tests with alpha = 0.05. RESULTS: OptiBond FL and One-Step showed less microleakage at the cementum margins compared to their multi-step versions. At the enamel margins Tenure Quik showed less microleakage compared to Tenure, and none of the other DBSs tested showed significant dye penetration at that interface. All DBSs showed significantly less microleakage at the enamel margins compared to the cementum margins except for OptiBond FL and One-Step that did not show any significant dye penetration at the cementum margins as well.  相似文献   

19.
Although variation in finishing techniques has been shown to affect microleakage, little research has been published on the influence of finishing time on the marginal sealing ability of new generation composite bonding systems. The objective of the present study was to evaluate the influence of finishing time on the enamel and dentine marginal sealing ability of four new generation composite systems. Two class V preparations, which were solely in enamel or dentine, were made on the buccal surfaces of 96 freshly extracted molar teeth. The teeth were randomly divided into four groups of 24 and restored with composite resin (Silux Plus) utilizing the following bonding systems: Scotchbond Multi-purpose, Fuji Bond LC, Prime & Bond 2.0 and Bisco One-step. Half of the restorations in each group were finished immediately after light polymerization and stored for 1 week. For the remaining restorations, finishing was delayed for 1 week. The storage medium was isotonic saline at 37 degrees C throughout the experiment. All restorations were then thermocycled, subjected to dye penetration testing, sectioned and scored. The results suggest that the finishing of composite restorations, bonded with the bonding systems evaluated, should be carried out immediately after light polymerization. Delayed finishing does not improve but instead can be detrimental to the marginal seal of the restorations. The effects of delayed finishing are, however, both bonding system and tissue specific.  相似文献   

20.
Amalgambond Plus with a high-performance additive was evaluated for its ability to bond a resin composite or an amalgam alloy to deep dentin in primary teeth with nonretentive cavity preparations. The clinical performance of amalgam and resin composite mesio-occlusodistal restorations bonded with Amalgambond Plus was evaluated at 15 months and 2 and 3 years. There was no statistically significant difference in the retention, marginal adaptation, secondary caries, and post-operative sensitivity over the times of the evaluation or between amalgam and resin composite restorations. After 3 years, most of the teeth were extracted because it was their exfoliation time, and 29 restorations limited within buccal and lingual cusps were evaluated for marginal leakage. There were no significant differences in microleakage between amalgam and resin composite restorations lined with Amalgambond Plus. Amalgambond Plus has the potential for serving successfully as a cavity liner with either amalgam or resin composite restorations.  相似文献   

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