An evaluation of a glass ionomer luting agent: bacterial leakage

This study quantitatively evaluates the bacterial leakage beneath crowns cemented with a glass ionomer cement compared with those cemented with a polycarboxylate cement or a varnish plus zinc phosphate cement. Bacterial samples were taken from beneath full crowns cemented with the test luting agents 3, 10, and 56 days after cementation. Two-way analysis of variance of the resultant data showed a significant increase in bacterial counts for zinc phosphate, a significant decrease for polycarboxylate, and no change for glass ionomer. These findings suggest that bacterial leakage may not be the reason for the reported poor clinical response associated with glass ionomer luting agents.     

Pulpal response to a hybrid composite resin inlay bonded with a newly developed resin-modified glass ionomer luting cement

This study evaluated the pulpal response of hybrid composite resin inlay luted with a resin-modified glass ionomer cement, and compared it with a glass ionomer cement and an amalgam. Cervical cavities were prepared in monkey teeth. A resin-modified glass ionomer luting cement (Ionotite F, Tokuyama Dental Corp.) was applied to the teeth in one of the experimental groups, and then hybrid composite resin inlays (Estenia, Kuraray Medical Inc.) were bonded to the cavities. The teeth were extracted after 3, 30, and 90 days and stained with Hematoxylin and Eosin staining or Brown and Brenn gram stain for bacterial observation. No serious inflammatory reaction of the pulp, such as necrosis or abscess formation, was observed in any of the experimental groups. No bacterial penetration along the cavity walls was detected in the resin-modified glass ionomer luting cement group. Hence, the resin-modified glass ionomer luting cement showed an acceptable biological compatibility with monkey pulp.     

A comparison between zinc phosphate and glass ionomer cement in orthodontics

In the past orthodontic band cementation has relied heavily on mechanically retentive cements such as zinc phosphate luting agents. The clinical performance of a glass ionomer cement (GIC), a chemically retentive cement, was evaluated against a conventional zinc phosphate cement (ZP). The recementation values for ZP were significantly higher over a 2-year treatment period than those of GIC. Failures between cement and enamel, and cement and stainless steel were noted for the ZP. Glass ionomer cement had significantly better retentive strength to enamel than to band material. Moisture contamination does not appear to be a problem in orthodontic band cementation with glass ionomer cement.     

Leakage of various types of luting agents

Freshly extracted molar teeth were prepared for complete cast gold crowns cemented with either zinc phosphate cement, polycarboxylate cement, glass ionomer cement, a resin luting agent, or a zinc oxide-eugenol temporary cement. The specimens were tested at 1-, 6-, and 12-month intervals with radioactive 45Ca. The specimens were sectioned, autoradiographs were made, and the marginal leakage was evaluated on a scale of 0 to 3. The results showed that zinc phosphate, polycarboxylate, and glass ionomer cements are equally suited for permanent cementation of restorations. The resin luting agent showed high initial leakage, indicating that it is not as desirable for permanent cementation purposes. The zinc oxide-eugenol cement showed increased leakage with time but is well suited for its indicated purpose, temporary cementation.     

Demineralization resistance and tensile bond strength of four luting agents after acid attack

Resistance to acid demineralization provided by luting agents adjacent to enamel was evaluated for four different luting agents: composite resin, glass ionomer, polycarboxylate, and zinc phosphate cement. Cement solubility and enamel demineralization after acid attack at pH 3.0 were measured radiographically and calculated using computer-aided design. Tensile bond strength of a miniature crown seated on an accurately prepared preparation was evaluated after acid attack using an Instron instrument. Crown retention after 12 days was greater for the polycarboxylate (2,000 kg/m2) than the zinc phosphate cement (500 kg/m2). Crown retention for the glass ionomer (1,100 kg/m2) and composite resin luting agent (1,400 kg/m2) were similar statistically after 21 days of acid exposure. Cement washouts for zinc phosphate and polycarboxylate were similar, and were greater than either glass ionomer or composite resin luting agent. The amount of demineralization related to cements was, from greatest to least: zinc phosphate, polycarboxylate, composite resin, glass ionomer. Fluoride release was concluded to be initially effective in reducing enamel solubility in spite of cement solubility.     

Pulpal response to an anhydrous glass ionomer luting cement

This investigation was designed to study the pulpal responses to Aquacem, an anhydrous glass ionomer luting cement, and to compare the results with those previously obtained for a conventional glass ionomer luting cement, Chembond. The study was carried out according to the BSI (1980) recommendations for testing restorative materials in vivo. Aquacem caused more pulpal inflammation than the control material, Kalzinol, though by an indirect mechanism. The statistical model demonstrated a significant association between bacterial presence within the experimental cavity and pulpal inflammation. The type of restorative material has no direct association with the degree of inflammation, but the model suggests that it exerts an indirect influence via its antibacterial properties and hence its influence on microbial microleakage.     

Pulpal response to two semihydrous glass ionomer luting cements

This study compared the pulpal responses to two innovative semihydrous glass ionomer luting cements (STA and ZIN) with those previously obtained for a conventional anhydrous glass ionomer luting cement, Aquacem. ZIN contained zinc oxide in the formulation. The study was conducted according to the BSI (1989) recommendations for testing restorative materials in vivo. ZIN was associated with minimal pulpal changes and microbial microleakage, and differed little from the control material, Kalzinol. The pulpal response to STA was similar to that observed for Aquacem, but was associated with less microbial microleakage. The statistical model demonstrated a significant association between bacterial presence within the experimental cavity and pulpal inflammation. The closer that bacteria were to the pulp, the more severe was the ensuing inflammation.     

Clinical performance of pressed ceramic inlays luted with resin-modified glass ionomer and autopolymerizing resin composite cements

STATEMENT OF PROBLEM: Several in vitro studies have been published showing the incapability of the chemical cure of dual-cured resin composite luting agents to compensate for absence of visible light activation. PURPOSE: This study evaluated and compared pairs of Empress ceramic inlays luted with 2 chemical-cured luting agents: a resin-modified glass ionomer cement and a resin composite within individual patients. MATERIAL AND METHODS: Seventy-nine ceramic inlays were placed in class II cavities in 29 patients. In each patient half of the inlays were luted with a resin-modified glass ionomer cement and the other half with a chemical-cured resin composite cement. The inlays were evaluated clinically, according to modified USPHS criteria, at baseline, after 6 months, and 1 and 2 years. RESULTS: No failed inlays were observed during the 2-year follow-up. A slight ditching of the cement margins was observed in both luting groups. No significant difference was seen between the 2 luting techniques. CONCLUSION: IPS Empress inlays luted with both chemical-cured luting agents functioned satisfactorily in the short-term follow-up. Longer observation periods are necessary to evaluate the long-term clinical behavior of both luting techniques.     

Pulpal response to an anhydrous glass ionomer luting cement

Abstract This investigation was designed to study the pulpal responses to Aquacem®, an anhydrous glass ionomer luting cement, and to compare the results with those previously obtained for a conventional glass ionomer luting cement, Chembond®. The study was carried out according to the BSI (1980) recommendations for testing restorative materials in vivo. Aquacem caused more pulpal inflammation than the control material, Kalzinol®, though by an indirect mechanism. The statistical model demonstrated a significant association between bacterial presence within the experimental cavity and pulpal inflammation. The type of restorative material has no direct association with the degree of inflammation, but the model suggests that it exerts an indirect influence via its antibacterial properties and hence its influence on microbial microleakage.     

Acidity of glass ionomer cements during setting and its relation to pulp sensitivity

Recent findings regarding pulp sensitivity to luting glass ionomer cements have aroused controversy as to the cause of the problem. Contributing factors may include chemical irritation from the material and leakage. The pH changes during setting were determined for three glass ionomer cements, a zinc phosphate cement, and a polycarboxylate cement. The data showed that the glass ionomer luting cements may show lower pH values for longer times than the other cements. This initial acidity, involving a prolonged period at pH below 3, coupled with cytotoxicity of other ingredients, may lead to damaging effects on the pulp when manipulation of the material and tooth preparation and cementation procedures are less than ideal.     

Evaluation of load at fracture of Procera AllCeram copings using different luting cements.

PURPOSE: The current study investigated the effect of different luting agents on the fracture resistance of Procera AllCeram copings. METHODS: Six master dies were duplicated from the prepared maxillary first premolar tooth using nonprecious metal alloy (Wiron 99). Thirty copings (Procera AllCeram) of 0.6-mm thickness were manufactured. Three types of luting media were used: zinc phosphate cement (Elite), glass ionomer cement (Fuji I), and dual-cured composite resin cement (Panavia F). Ten copings were cemented with each type. Two master dies were used for each group, and each of them was used to lute five copings. All groups were cemented according to manufacturer's instructions and received a static load of 5 kg during cementation. After 24 hours of distilled water storage at 37 degrees C, the copings were vertically compressed using a universal testing machine at a crosshead speed of 1 mm/min. RESULTS: ANOVA revealed significant differences in the load at fracture among the three groups (p < 0.001). The fracture strength results showed that the mean fracture strength of zinc phosphate cement (Elite), glass ionomer cement (Fuji I), and resin luting cement (Panavia F) were 1091.9 N, 784.8 N, and 1953.5 N, respectively. CONCLUSION: Different luting agents have an influence on the fracture resistance of Procera AllCeram copings.     

The effect of adhesive luting agent-dentinal surface interactions on film thickness.

This study investigated the effect of luting agent-dentinal surface interactions on the film thicknesses of new adhesive luting agents. The method was in compliance with American National Standards Institution/American Dental Association (ADA) Specification No. 8 for zinc phosphate cement. In the control groups the luting agents were placed between two glass plates, as described in ADA Specification No. 8, but in the test groups the luting agents were positioned between a glass and a dentinal plate. The materials selected were zinc phosphate cement, glass ionomer cement, polycarboxylate cement, and a resinous cement with a dentinal bonding agent. A two-way analysis of variance was performed, and t tests were computed to compare glass with the dentinal plate within each material. Zinc phosphate and glass ionomer cements exhibited a significant decrease in film thickness when measured in contact with dentin, as compared with contact with the glass plate. However, polycarboxylate cement and the resinous cement with its dentin bonding agent showed a slight nonsignificant increase when contacting dentin, as compared with the glass plate. An explanation was offered and suggestions were made regarding future research.     

Comparison of pulpal sensitivity between a conventional and two resin-modified glass ionomer luting cements

This clinical study compared handling and any short-term tooth sensitivity associated with using one conventional and two resin-modified glass ionomer cements marketed for luting gold and ceramometal crowns. The patient's response to a 10-second blast of air applied to the vital tooth was scored pre-operatively and again within a one-to-four week post-cementation recall period. A score was also recorded for any sensitivity present at the time of cementation of the crown on the unanesthetized tooth. All three cements were easy to mix and place. Most of the teeth had no response to pulpal stimulation pre-operatively, associated with the cementation procedure or post-cementation, and there were no instances of severe sensitivity recorded. For all cements, the level of post-cementation tooth sensitivity was similar, and less than that found pre-operatively.     

Human pulp response to resin cements used to bond inlay restorations.

OBJECTIVE: The aim of this study was to evaluate the pulp response following cementation of inlays using two different resin cements. METHODS: Deep Class V cavities were prepared on the buccal surface of 34 sound human premolars. Impressions were taken and inlays were prepared which were cemented with the following luting materials-Group 1: Rely X Unicem (3M ESPE); Group 2: Variolink II (Ivoclar Vivadent). In Group 3 (control), after lining the cavity floor with Dycal (Dentsply Caulk) the inlays were cemented with Rely X Unicem. Four additional teeth were used as an intact control group. For Variolink II, the adhesive system Excite was used as part of the cementation procedure. After 7 or 60 days, the teeth were extracted and processed for histological assessment. RESULTS: At 7 days, Rely X Unicem and Variolink II system triggered in two samples a mild and moderate inflammatory response, respectively. At 60 days, the pulpal response decreased for both groups. A discrete persistent inflammatory response occurred in Group 2 in which displacement of resin components across the dentin tubules was observed. In the control group, normal histological characteristics were observed. The inflammatory response and tissue disorganization were related to the remaining dentin thickness between the cavity floor and the pulp tissue. SIGNIFICANCE: Techniques for inlay cementation using distinct luting cements may cause specific pulpal damage. Variolink II associated with the adhesive system Excite cause more aggressive effects to the pulp-dentin complex than Rely X Unicem cement when both are used to cement inlay restorations.     

Dentin bonding of cements. The bonding of cements with dentin in combination with various indirect restorative materials

The number of both luting agents and restorative materials available on the market has rapidly increased. This study compared various types of luting agents when used to bond different indirect, laboratory restorative materials to dentin. Cylinders were produced of six restorative materials (gold alloy, titanium, feldspathic porcelain, leucite-glass ceramic, zirconia, and an indirect resin composite). Following relevant pretreatment, the end surface of the cylinders were luted to ground, human dentin with eight different luting agents (DeTrey Zinc [zinc phosphate cement], Fuji I [conventional glass ionomer cement], Fuji Plus [resin-modified glass ionomer cement], Variolink II [conventional etch-and-rinse resin cement], Panavia F2.0 and Multilink [self-etch resin cements], RelyX Unicem Aplicap and Maxcem [self-adhesive resin cements]). After water storage at 37 °C for one week, the shear bond strength of the specimens was measured and the fracture mode was examined stereo-microscopically. Restorative material and luting agent both had a significant effect on bond strength and there was a significant interaction between the two variables. The zinc phosphate cement and the glass ionomer cements resulted in the lowest bond strengths, whereas the highest bond strengths were found with the two self-etch and one of the self-adhesive resin cements.     

The Effect of Die Spacer on Retention and Fitting of Complete Cast Crowns

PURPOSE: This study evaluated the effect of die spacer on the fit and retention of complete cast crowns by using three different cements. MATERIALS AND METHODS: Standardized full crown restoration preparations were completed on 99 extracted molar teeth, impressions were made with poly(vinyl siloxane), and stone dies were made. Dies were covered with four layers of die spacer using three techniques: (1) covering the occlusal and 1/3 of the axial surfaces, (2) covering the occlusal and 2/3 of the axial surfaces, and (3) covering the entire preparation except the apical 0.5 mm of the preparation. Complete metal crowns were cast using Pors-on 4 alloy. Crowns were then assigned to one of three luting agent groups: resin modified glass ionomer cement, resin cement, or zinc phosphate cement. The castings were placed on their respective teeth and the marginal opening was recorded by two methods: 72 specimens were examined before and after cementation using optical microscopy with 0.001 mm resolution, and 27 specimens were examined after cementation with scanning electron microscopy. After cementation, the teeth were thermocycled for 700 cycles between 5 degrees C and 55 degrees C. The tensile retentive strength was measured on a universal testing machine with a crosshead speed of 0.5 mm/min. The data obtained for the fitting were recorded in millimeters and the data for the tensile retentive strength were recorded in KgF. The statistical analysis was performed by analysis of variance and post hoc Tukey's test (p< 0.05). RESULTS: Before cementation, better marginal fit was obtained when the die spacer covered all but the area 0.5 mm short of the margin of the preparation; however, after cementation, the resin modified glass ionomer cement group had the best fit with the same application of die spacer. Castings luted with resin cement required the greatest tensile force to produce cement failure. CONCLUSIONS: Increasing the area of the die surface covered with spacer improved the fit of the cast restoration. After cementation, the resin modified glass ionomer showed better adaptation; however, the optical microscopy and scanning microscopy correlate well. Resin cement had the highest resistance to tensile forces.     

Resin-modified glass ionomer cement and self-cured resin composite luted ceramic inlays. A 5-year clinical evaluation.

OBJECTIVE: This study evaluated IPS Empress ceramic inlays luted with two chemical-cured luting agents, a resin-modified glass ionomer cement (Fuji Plus (F)) and a resin composite (RC) (Panavia 21 (P)). METHODS: Seventy-nine ceramic inlays were placed in Class II cavities in 29 patients. At least two inlays were placed in each patient to compare the luting techniques intra-individually. In each patient half of the inlays were luted with F and the other half with P. The inlays were evaluated clinically, according to modified USPHS criteria (van Dijken, 1986), at baseline, after 6 months, and yearly during 5 years. RESULTS: At 5 years, 71 inlays were evaluated. Two small partial fractures were observed at 3 years (1P, 1F). One inlay showed recurrent root caries at 4 years (P). Four inlays, two in each group showed non-acceptable color match (2P, 2F). Small defects were observed in 4 inlays (2P, 2F). A slight ditching of the cement margins was observed in both luting groups but did not seem to increase during the second half of the evaluation. No significant difference in durability was observed between the two luting agents. SIGNIFICANCE: IPS Empress inlays luted with the chemical-cured RC and the resin-modified glass ionomer cement functioned satisfactory during the 5 years follow-up.     

4种玻璃离子水门汀对ITI基台与金属内冠之间粘接力的比较研究

目的：研究4种玻璃离子类水门汀对ITI种植系统标准颈粘接固位基台和金属内冠之间的粘接力。方法将10只金属内冠与10只I T I标准颈粘接固位基台分别使用以下4种水门汀进行交叉粘固：A组为玻璃离子水门汀（日本）;B组为树脂加强型玻璃离子水门汀（美国）;C组为暂时粘固用玻璃离子水门汀（日本）;D组为玻璃离子水门汀（德国）;粘固后测试并记录样本粘接力（N）,同时观察并记录粘固界面的断裂模式,最后,对粘接力进行统计学处理。所有内冠和基台经清洗后重复使用。结果4种水门汀的粘接力及由大至小的排列顺序为C组（183.6±29.4） N〉D组（153.4±36.2） N〉B组（144.4±41.1） N〉A组（109.9±25.7）N,其中C组的粘接力最高,A组的粘接力最低,A组显著低于其它3种水门汀（P〈0.05）。对样本的断裂面观察显示,A组和D组样本断裂面发生在水门汀和基台表面之间,而B组和C组样本的断裂面则呈现混合断裂的模式。结论2种玻璃离子水门汀和树脂加强型玻璃离子水门汀都具有临床可接受的粘接力,而暂时粘固用玻璃离子水门汀因粘接力太大,不适用对种植牙冠进行暂时粘固。     

Glass ionomer as a luting material

Glass ionomer cements have been accepted by many practitioners as reliable luting materials. However, some dentists have condemned them because of frequent postoperative tooth sensitivity and difficult working characteristics. Reasons for apparent erratic postoperative behavior of glass ionomer luting agents are discussed. Comparisons with other commonly used cements are made, and a suggested clinical cementation procedure is described.     

Pulpal responses to ionomer cements--biological characteristics

When glass ionomer cements were initially introduced, the pulpal responses were considered milder relative to other cements. However, the results mainly came from the application of glass ionomer cements as restorative materials. When ultimately tested with the basic laws of biocompatibility required of other cements, especially a luting agents, little difference has been shown. The judicious use of calcium hydroxide is highly recommended.