Comparison of fluoride release protocols for in-vitro testing of 3 orthodontic adhesives.

The objective of this study was to compare the fluoride release of 3 orthodontic adhesives using disks and bracketed teeth with different storage protocols. The adhesives used were a resin-modified glass ionomer (RMGI) (Fuji Ortho LC; GC America, Aslip, Ill), a polyacid-modified composite resin (PMCR)(Assure; Reliance Orthodontic Products, Itasca, Ill), and a composite control, Transbond XT (3M Unitek, Monrovia, Calif). Metal brackets were bonded to the buccal and lingual surfaces of 120 extracted human premolars. Five plastic containers holding 4 teeth (8 brackets) were used for each adhesive protocol. The samples were stored in containers holding 4 mL of deionized water at 37 degrees C for 28 and 84 days for the brackets and disks, respectively. The bracketed samples released larger initial amounts of fluoride compared with the disk samples during the first 5 to 6 days for both fluoride-releasing adhesives. The PMCR (Assure) released more fluoride (mg/cm(2)/day) than did the RMGI (Fuji Ortho LC) in all protocols with the exception of daily protocols when values diminished below the RMGI values near the 24th day and between the 56th and the 70th days for the bracketed and disk samples, respectively. Inconsistent values for fluoride release were noted in the bracket and disk samples when compared with daily versus cumulative water changes. Daily water changes revealed higher fluoride release levels (brackets), but this trend was not evident in the disk samples. Daily water changes may yield more clinically relevant data on fluoride release.     

A comparison of fluoride release by resin-modified GIC and polyacid-modified composite resin.

The objective of this study was to compare the fluoride release of 2 fluoride-containing orthodontic adhesives from bracketed teeth and adhesive disks, a resin-modified glass ionomer cement (Fuji Ortho LC, encapsulated; GC America Corp, Aslip, Ill) and a polyacid-modified composite resin (Assure; Reliance Orthodontic Products, Itasca, Ill). A composite resin without fluoride (Transbond XT; 3M Unitek, Monrovia, Calif) was used as a reference control. Metal brackets were bonded to the buccal surfaces of 120 human premolars (40 teeth per adhesive), and disks were made from each adhesive. The deionized storage water was changed, and fluoride release was measured at specified intervals up to 28 days for the bracketed teeth and up to 150 days for the disks. Fuji Ortho LC released 75% more accumulated fluoride than Assure (6.61 microg/bracket vs 3.77 microg/bracket) from bracketed teeth over the 28-day observation period. Assure released more fluoride per day than did Fuji Ortho LC from the disks during the first 3 months. For the rest of the 150-day period, Fuji Ortho LC released more fluoride per day than did Assure. The amount of fluoride released by these materials varied dramatically with different water-changing protocols. The large discrepancy between fluoride released from disks compared with that released from bracketed teeth suggests that caution must be used in extrapolating fluoride-release levels of adhesive disks to in vivo treatment conditions.     

Demineralization around orthodontic brackets bonded with resin-modified glass ionomer cement and fluoride-releasing resin composite.

PURPOSE: Enamel demineralization adjacent to orthodontic brackets is one of the risks associated with orthodontic treatment. Glass ionomer cements have been shown to decrease enamel demineralization adjacent to brackets and bands but do not exhibit bond strengths comparable to resin composites. The purpose of this in vitro study was to compare a fluoride-releasing resin composite versus a resin-modified glass ionomer cement for inhibition of enamel demineralization surrounding orthodontic brackets. METHODS: Forty-five teeth were randomly assigned to 3 groups of 15 teeth. Fifteen were bonded with Concise (3M), a non-fluoride-releasing resin composite (control); 15 teeth were bonded with Light Bond (Reliance), a fluoride-releasing resin composite; and 15 teeth were bonded with Fuji Ortho LC (GC Corporation), a resin-modified glass ionomer cement. The teeth were placed in an artificial caries solution to create lesions. Following sectioning of the teeth in a buccolingual direction, polarized light microscopy was utilized to evaluate enamel demineralization adjacent to the orthodontic bracket. The area of the lesion was measured 100 microns from the orthodontic bracket and bonding agent. RESULTS: MANOVA (P < .0001) and Duncan's test (P < .05) indicated the resin-modified glass ionomer cement (Fuji Ortho LC) and the fluoride-releasing resin composite (Light Bond) had significantly less adjacent enamel demineralization than the non-fluoride-releasing resin composite control. However, there was no significant difference between the resin-modified glass ionomer cement and the fluoride-releasing resin composite. CONCLUSIONS: Based on the results of this in vitro study, it can be concluded that Fuji Ortho LC and Light Bond exhibit significant inhibition of adjacent demineralization compared to the non-fluoride-releasing control.     

Enamel demineralization adjacent to orthodontic brackets bonded with hybrid glass ionomer cements: An in vitro study

Enamel demineralization is recognized as a possible side effect of bonding orthodontic brackets with composite resins. Fluoride-releasing restorative materials have been shown to inhibit tooth demineralization. The purpose of this study was to evaluate two fluoride-releasing hybrid glass ionomer bonding agents for inhibition of enamel demineralization surrounding orthodontic brackets under two experimental conditions. This in vitro study used 72 extracted human premolars. Twenty-four teeth were bonded with Advance resionomer, 24 were bonded with Fuji Ortho LC hybrid glass ionomer and 24 were bonded with Transbond XT composite resin as the control. The teeth were cycled in an artificial caries challenge three times daily for 30 days. Half of the teeth in each group were brushed twice daily with a fluoridated dentifrice, and the other half were not brushed. Demineralization of enamel surrounding orthodontic brackets was evaluated with polarized light microscopy. Enamel lesions were photographed under maximum illumination. Images were projected, and demineralized areas were traced. Both average depth and area were measured with a sonic digitizer. Analysis of variance (P < .0001) and Duncan’s test (P < .05) indicated significant differences in depth and area of demineralized enamel such that lesion size was: Transbond XT no brush > Transbond XT brush > Advance no brush = Advance brush = Fuji Ortho LC no brush = Fuji Ortho brush. The promising results of this in vitro study warrant further clinical investigation of hybrid glass ionomer adhesives as orthodontic bonding agents to minimize enamel demineralization. (Am J Orthod Dentofacial Orthop 1998;114:668-74)     

Inhibition of artificial secondary caries in root by fluoride-releasing restorative materials

This investigation evaluated the fluoride-releasing properties of various fluoride-releasing restorative materials, including resin-modified glass-ionomer cements (Fuji ionomer TypeII LC, Photac-Fil Aplicap, Vitremer), compomers (Ionosit FIL, Compoglass, Dyract) and fluoride-releasing resin composites (Heliomolar radiopaque, Degufill mineral). The study also estimated the effects of those materials on the inhibition of artificial secondary caries around restorations using a bacterial caries-inducing system. The amount of fluoride released from the materials in deionized water was measured every one week for 10 weeks. Class V cavities with the gingival margin located in the root were prepared in extracted human premolars and restored with each of the materials. The restored teeth were incubated in the bacterial artificial caries chamber, and the artificial lesion created around the restoration was observed microradiographically. The resin-modified glass-ionomer cements released the largest amount of fluoride and created a thick radio-opaque zone in the artificial lesion along the restoration-dentin interface. These results indicated that the fluoride-releasing restorative materials have the potential to inhibit secondary caries formation around restorations. Resin-modified glass-ionomer cements presented a particularly strong effect, compared with compomers and fluoride-releasing resin composites.     

Effect of fluoride varnish on demineralization adjacent to brackets bonded with RMGI cement.

Far too often a less-than-optimal esthetic result occurs after orthodontic treatment due to demineralization of enamel adjacent to fixed orthodontic appliances in patients with inadequate oral hygiene. In vitro studies have shown that a resin-modified glass ionomer (RMGI) cement and a fluoride varnish might help clinicians combat this problem. The purpose of this study was to evaluate, in vitro, the effect of a fluoride-releasing cavity varnish on inhibition of enamel demineralization adjacent to orthodontic brackets bonded with RMGI and composite resin cements. Brackets were bonded to 48 extracted human third molars. Half were bonded with a composite resin (Transbond, 3M Unitek, Monrovia, Calif) and half with an RMGI (Fuji Ortho LC, GC America, Alsip, Ill). Each group was further divided into 2, with half receiving an application of fluoride-releasing varnish (Duraflor, Pharmascience, Montreal, Québec, Canada). The samples were cycled in an artificial caries solution for an hour twice daily for 31 days. After each caries challenge, the teeth were brushed with a soft toothbrush to simulate normal mechanical wear of the varnish. The loss of fluoride varnish was timed. Teeth were sectioned longitudinally and photographed under polarized light microscopy. Mean lesion depth was measured, and analysis of variance (ANOVA) (P 相似文献   

Comparison of bond strength of three adhesives: composite resin, hybrid GIC, and glass-filled GIC.

The objective of this study was to compare 3 orthodontic adhesives in the areas of shear-peel bond strength, location of adhesive failure, and extent of enamel cracking before bonding and after debonding of orthodontic brackets. The adhesives included a composite resin control (Transbond XT; 3M/Unitek, St Paul, Minn), a resin-modified glass ionomer cement (Fuji Ortho LC; GC America Corp, Alsip, Ill), and a polyacid-modified composite resin under dry and saliva-contaminated conditions (Assure; Reliance Orthodontic Products Inc, Itasca, Ill). Metal brackets were bonded to the buccal surfaces of 160 (4 groups of 40) human premolars. The bonded teeth were stored in deionized water at 37 degrees C for 30 days and thermocycled for 24 hours before debonding with a Universal Instron (Instron Corp, Canton, Mass) testing machine. The extent of cracking in the buccal surfaces was evaluated under 16x magnification before bonding and after debonding. Although the bond strength of the composite resin control (20.19 MPa) was significantly greater (P <.05) than that of the adhesives in the other groups, clinically acceptable shear-peel bond strengths were found for all adhesives (Fuji Ortho LC = 13.57 MPa, Assure-dry = 10.74 MPa, Assure-wet = 10.99 MPa). The bond strength for the Assure adhesive was not significantly affected by saliva contamination. The sample of extracted premolars used in this study displayed a greater frequency of buccal surface enamel cracking (46.7%) than that reported in the literature for in vivo premolars (7.8%-10.2%), which was possibly due to the extraction process. The frequency of enamel cracking in a subset of this sample (n = 34) increased from 46.4% at prebonding to 62.4% at postdebonding as a result of the forces of debonding.     

含氟充填材料释氟吸氟和再释氟的研究

目的 为了研究含氟充填材料能否长期稳定释放氟而发挥抗龋效能,本文观察了玻璃离子水门汀和含氟复合树脂在用含氟牙膏处理前后两个时期的释氟情况。方法 第一阶段,将玻璃离子水门汀和含氟复合树脂各６个标本,分别浸泡于去离子水中,测定其在不同时间氟的放量;第二阶段。用含氟牙膏处理各标本后,再测定其在不同时间氟的释放量。结果 当这两允填材料释氟水平降低后,用含氟牙膏处理,琪 释放量明显回升     

In vitro study of 24-hour and 30-day shear bond strengths of three resin–glass ionomer cements used to bond orthodontic brackets

Interest in using composite resin–glass ionomer hybrid cements as orthodontic bracket adhesives has grown because of their potential for fluoride release. The purpose of this pilot study was to compare shear bond strengths of three resin–glass ionomer cements (Advance, Fuji Duet, Fuji Ortho LC) used as bracket adhesives with a composite resin 24 hours and 30 days after bonding. The amount of adhesive remaining on the debonded enamel surface was scored for each adhesive. Mesh-backed stainless-steel brackets were bonded to 100 extracted human premolars, which were stored in artificial saliva at 37° C until being tested to failure in a testing machine. The hybrid cements, with one exception, had bond strengths similar to those of the composite resin at 24 hours and 30 days. Fuji Ortho LC had significantly lower bond strengths (ANOVA p ≤ 0.05) than the other adhesives at 24 hours and 30 days when it was bonded to unetched, water-moistened enamel. Adhesive-remnant scores were similar for all cements, except for cement Fuji Ortho LC when it was bonded to unetched enamel. The resin–glass ionomer cements we tested appear to have bond strengths suitable for routine use as orthodontic bracket–bonding adhesives. (Am J Orthod Dentofacial Orthop 1998;113:620-24.)     

Fluoride release of glass ionomer-based luting cements in vitro.

STATEMENT OF PROBLEM: There is considerable variation in generic formulation and in reported fluoride release from resin-modified glass ionomer luting cements. PURPOSE: This study compared fluoride release from 2 generically similar resin-modified glass ionomer luting cements (Vitremer and Advance) with release from 2 conventional glass ionomer luting cements (Ketac-Cem and Fuji I). MATERIAL AND METHODS: Ten specimen disks of each of the 4 luting cements were fabricated and immersed in deionized water in individual polystyrene jars. The jars were stored in a humidor at 37 degrees C between test periods. At the same time each day, for 28 days, fluoride release from each specimen disk was measured in parts per million by testing the storage water. RESULTS: The 4 luting cements tested showed an initial high concentration of fluoride release during the first week, followed by a gradual decrease over the study period. Vitremer luting cement demonstrated the greatest mean cumulative fluoride release in parts per million over the study period (198), followed by Fuji I (140), Ketac-Cem (110), and Advance (99) luting cements. CONCLUSIONS: Resin-modified glass ionomer luting cements showed fluoride release comparable to the conventional glass ionomer luting cements. Vitremer luting cement released more fluoride over the 28-day period than the other cements.     

An investigation into the bonding of orthodontic attachments to porcelain

This study assessed bonding of orthodontic brackets to porcelain teeth using two different surface preparation techniques and comparing two bonding systems, Fuji Ortho L.C. and Transbond. Four groups of 20 porcelain premolar teeth were bonded with metal orthodontic brackets (0.022 inch Minitwin, 3M Unitek) according to the following protocol: Transbond with a phosphoric acid etch (group 1), Transbond with a hydrofluoric acid etch (group 2), Fuji Ortho L.C. with a hydrofluoric acid etch (group 3), and Fuji Ortho L.C. with a phosphoric acid etch (group 4). All groups were bonded with a silane coupling agent. The teeth were debonded with an Instron universal testing machine. Bond strength, site of bond failure and adhesive remnant index (ARI) were recorded for each group. Differences between groups were analysed statistically. The composite resin groups (groups 1 and 2) had the highest mean bond strength values at 7.9 and 9.7 MPa, respectively. The resin-modified glass ionomer cement groups (RMGIC; groups 3 and 4) had the lowest mean bond strength values at 6.3 and 1.8 MPa, respectively. The mean bond strength of group 3 was significantly lower than all other groups (P < 0.0001). The Fuji groups had also significantly (P < 0.001) lower ARI scores than the composite groups (groups 1 and 2). Most samples experienced porcelain surface damage, except group 4. In conclusion, the highest bond strength levels were achieved with a conventional composite resin cement (groups 1 and 2). No significant differences in bond strength were found between the hydrofluoric and phosphoric acid etch technique.     

A method for producing controlled fluoride release from an orthodontic bracket

The aim of this study was to manufacture and test, in vitro, a novel modification to provide fluoride-releasing orthodontic brackets. Thirty-two orthodontic brackets were drilled to produce a recess (approximately 1.3 mm in diameter and 0.7 mm in depth) at the centre of the bracket base. Four materials, with and without the addition of sodium fluoride, a glass ionomer cement (Ketac Cem micro), a resin-modified glass ionomer cement (RMGIC; GC Fuji Ortho LC), a zinc phosphate (Zinc Cement Improved), and a resin (Transbond XT) were used to fill the recess in the bracket base. Fluoride release was measured daily during the first week and then weekly for 10 weeks. An ion chromatograph with suppressed conductivity was used for free fluoride ion determination. Statistical analysis to determine the amount of flouride release was undertaken using analysis of variance and Tukey's test. During the first 2 weeks, the resin group, with the addition of 38 per cent sodium fluoride added, released significantly more free fluoride (P < 0.05), but after 2 weeks the fluoride release markedly decreased. After 5 weeks, the RMGIC group, with 15 per cent added sodium fluoride, had significantly higher (P < 0.05) daily fluoride release than the other groups. The findings demonstrated that an appropriate fluoridated material can be used as a fluoride-releasing reservoir in a modified orthodontic bracket to enable it to release fluoride over the period of fixed appliance treatment.     

Bonded molar tubes--an in vitro evaluation

This study aimed to evaluate the mean shear bond strength of molar tubes with micro-etched bases bonded with either a compomer (Ultra Band-Lok), a resin-modified glass ionomer cement (3M Multi-Cure or Fuji Ortho LC), or a light-cured resin adhesive (Transbond). The amount of adhesive remaining on the tooth surface following tube removal was assessed also. Finally, survival time of molar tubes bonded with each bonding agent was assessed following simulated mechanical fatigue in a ball mill. A total of 120 extracted human third molars were collected and randomly divided into 4 test groups. Thirty teeth (20 to assess debonding force and 10 to assess survival time) were bonded with each adhesive according to the manufacturers' instructions. Debonding was carried out using a Nene M3000 testing machine with a crosshead speed of 0.5 mm/min. The mean shear bond strength of tubes bonded with Transbond was significantly less than that of those bonded with 3M Multi-Cure (P = .0036) or Fuji Ortho LC (P < .0001). Tubes bonded with Ultra Band-Lok also had significantly lower mean shear bond strength than those bonded with Fuji Ortho LC (P = .020). Distribution of adhesive remnant index scores only differed significantly between tubes bonded with 3M Multi-Cure or Transbond. Only I molar tube, bonded with Transbond, debonded in the ball mill at 5 hours, but at 50 hours there was no significant difference in the survival time of tubes bonded with any of the bonding agents. Compomer or resin-modified glass ionomer cements appear to be viable alternatives to light-cured resin adhesive for bonding molar tubes.     

Fluoride release from three glass ionomers, a compomer, and a composite resin in water, artificial saliva, and lactic acid

The amounts and the pattern of fluoride release from one metal-reinforced glass ionomer cement, two resin-modified glass ionomer cements, one compomer, and one composite resin placed in double-distilled water, artificial saliva, and lactic acid were evaluated in this study. Measurements of fluoride ion release were made for a total of 105 cylindrical specimens (10 mm in diameter and 1.5 mm in height). They were taken over a period of 16 weeks at the intervals of 4, 8, 12, and 24 hours, as well as 2, 3, 7, 14, 28, 56, and 112 days. The pattern of fluoride release was similar for all of the examined materials. The greatest amount of fluoride was released from the metal-reinforced glass ionomer Argion. The resin-modified glass ionomers Vitremer, Fuji II LC; the compomer Dyract; and the composite resin Tetric followed in ranking order. The pH of the environment strongly affected the fluoride release from the materials. There was a significant difference (P < 0.001) in the amounts of fluoride released in lactic acid vs water and artificial saliva, whereas, there was no significant difference (P > 0.05) in the amounts of fluoride released in water vs artificial saliva.     

Fluoride release from a new glass-ionomer cement

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.     

In vivo inhibition of demineralization around orthodontic brackets.

Demineralization around orthodontic appliances is a problem. Suboptimal oral hygiene, long intervals between appointments, and potentially poor patient cooperation with using fluoride dentifrices and mouth rinses necessitate a compliance-free means of preventing tooth decay. The hypothesis of this study was that fluoride released by glass ionomer cement inhibits the formation of carious lesions around orthodontic brackets in vivo. Brackets were bonded on 2 first premolars in 21 randomized, consecutively selected patients 11 to 18 years old. Eleven test-group subjects were bonded with fluoride-releasing glass ionomer cement, and 10 control subjects were bonded with composite resin (no fluoride). The teeth were extracted after 4 weeks, sectioned, and evaluated quantitatively by cross-sectional microhardness testing. Fluoride levels in patient saliva were measured by the Taves diffusion method in samples taken at days 0 (baseline), 1, 2, 3, 7, 14, 21, and 28 to determine whether fluoride from the glass ionomer cement influenced the overall intraoral fluoride levels. The results demonstrated significantly more demineralization around the brackets of the control patients (P <.01, Wilcoxon signed rank test). For whole-mouth salivary fluoride levels, no significant overall difference between the groups (P >.05) and no noticeable trend within groups (P >.05) were found. These results indicate that using fluoride-releasing glass ionomer cement for bonding orthodontic brackets successfully inhibited caries in vivo. This cariostatic effect was localized to the area around the brackets and was statistically significant after 4 weeks.     

Glass ionomer cements as luting agents for orthodontic brackets

The objectives of the present study were to (1) assess the shear bond strengths of resin-reinforced glass ionomer Fuji Ortho LC and GC Fuji Ortho cements under differing conditions and (2) compare their bonding performance with that of conventional resin composite bonding systems. A sample of 264 bovine incisors was divided into 22 groups of 12 teeth each and bonded with SPEED central incisor brackets. Enamel surfaces of the teeth in the two experimental groups were conditioned according to the manufacturer's instructions; moreover, groups unconditioned before bonding were also included under both wet and dry conditions. A self-cure composite resin (Phase II) and a light-cure composite resin (Transbond XT) served as controls and were etched with 37% phosphoric acid and bonded in a dry field. After incubation at 37 degrees C for 24 hours and for seven days, the specimens were tested to failure with a shear force in an Instron machine. The Adhesive Remnant Index (ARI) was used to assess the amount of resin left on the enamel surfaces after debonding. Selected specimens were examined using scanning electron microscopy. Statistical analyses included analysis of variance tests, t-tests, and correlation coefficient calculations and showed that no significant difference existed between the glass ionomer cements under wet or dry conditions, provided the enamel was conditioned with 10% polyacrylic acid before bonding. Both glass ionomer cements were thus acceptable for bonding. Transbond XT had the highest mean shear bond strength irrespective of the incubation period. A positive correlation was obtained between the ARI scores and bond strength.     

Selected mechanical properties of fluoride-releasing restorative materials

Mechanical properties, diametral tensile strength (DTS) and flexural strength (FS) of six fluoride releasing materials were measured and compared. The samples were prepared and tested according to ISO specifications. The materials included a glass ionomer (Fuji IX), a resin-modified glass ionomer (Photac-Fil), two compomers (F 2000; Dyract AP) and two composites (Solitaire; Tetric Ceram). The tests were performed after the materials were stored in distilled water (DTS) and phosphate buffered saline solution (FS) at 37 degrees C for 24 hours and one week. Fluoride-releasing composite resin had the highest flexural and diametral tensile strengths and were statistically stronger than compomers, followed by resin-modified glass ionomer and conventional glass ionomer. However, a notable exception to this general trend was Solitaire, a fluoride-releasing composite resin.     

Evaluating the effects of fluoride-releasing dental materials on adjacent interproximal caries.

BACKGROUND: The authors examined several restorative materials to evaluate their ability to inhibit demineralization and enhance remineralization of incipient carious lesions on the interproximal enamel of teeth adjacent to those restored with the materials. METHODS: Twenty-one subjects in need of a crown on a mandibular molar and a Class II inlay on an adjacent tooth took part in this six-phase study. Artificial enamel lesions were created and positioned within the interproximal portion of a crown. Lesions were photographed with polarized light microscopy and characterized before and after 30-day intraoral exposures. Each phase included the placement of a new section in the crown model and a new Class II inlay restorative material in the adjacent tooth. RESULTS: Results demonstrated that nonfluoridated resin composite, fluoridated resin composite and resin-modified glass ionomer restorative materials, when placed in subjects who brushed with a fluoridated dentifrice, demonstrated significantly (P < .05) less enamel demineralization than the nonfluoridated resin composite control placed in subjects who brushed with a nonfluoridated dentifrice. The resin-modified glass ionomer cement, however, even when brushed with a nonfluoridated dentifrice, exhibited significantly (P < .05) less demineralization than the nonfluoridated resin composite control brushed with a nonfluoridated dentifrice. CONCLUSIONS: Resin-modified glass ionomer cement appears to significantly inhibit demineralization of interproximal enamel of teeth adjacent to those restored with the material. CLINICAL IMPLICATIONS: Resin-modified glass ionomer cement restorations can enhance prevention of enamel demineralization on adjacent teeth.     

含氟牙釉质粘接剂释氟的实验研究

目的：研究国产含氟牙釉质粘接剂的释氟性能。方法：制备含氟牙釉质粘接剂I型和Ⅱ型的测试标本，以ORION720型离子选择性氟电极、参比电极测试氟离子浓度。结果：I型及Ⅱ型含氟牙釉质粘接剂均有氟离子释放，且在第一个24h后氟离子浓度下降显著，可维持21d左右；Ⅱ型含氟牙釉质粘接剂初始状态释放氟离子水平较高。结论：I型及Ⅱ型含氟牙釉质粘接剂均有释氟性能,而以Ⅱ型含氟牙质粘接剂较佳。