Strength Of Glass Ionomer Cement Research Articles

Investigating the Potential of Acacia nilotica-Enriched Glass Ionomer Cement: An Analysis of Antimicrobial Activity and Compressive Strength.

Background According to existing literature, introducing natural antibacterial agents into glass ionomer cement (GIC) has been associated with potential negative impacts on their strength properties. Hence, this study aims to explore the antibacterial effectiveness of glass ionomer cement enriched with Acacia nilotica and subsequently assess its compressive strength characteristics. Aim The objective of the study is to assess the antimicrobial effectiveness and compressive strength of glass ionomer cement modified with Acacia nilotica. Materials and methods The plant extract was incorporated into the conventional glass ionomer cement in three different proportions (powder GIC: extract: liquid GIC), divided into group I, group II, and group III with ratios of 2:1:1, 3:1:2, and 3:2:1 respectively. Additionally, a control group denoted as group IV was included without any modifications. Subsequently, the specimens were prepared, and their chemical structure was analyzed using Fourier transform infrared spectroscopy (FTIR), followed by testing for antimicrobial activity using the minimum inhibitory concentration (MIC) assay against Streptococcus mutans and Lactobacillus. The assessment of compressive strength was conducted following ISO 9917-1:2007 standards, and the recorded values represent the maximum force the specimen could withstand before fracturing. Results The antimicrobial effectiveness against Streptococcus mutans and Lactobacillus exhibited a notable increase in all modified specimens compared to the control group, with a significance level of p<0.05. Additionally, significant improvements in compressive strength were observed in group III (183.49±2.99) when compared to the remaining groups. The higher concentrations of the plant extract resulted in superior outcomes. Conclusion Therefore, the incorporation of Acacia nilotica into GIC shows promising potential as a restorative material. These investigations can provide valuable insights into the material's performance and durability, contributing to its potential application in dental restorations. Future research is needed to thoroughly investigate the bonding chemistry between Acacia nilotica and GIC, as well as to assess the extent of microleakage.

Comparative Evaluation of the Push-Out Bond Strength of Glass Ionomer Cement, Mineral Trioxide Aggregate, Biodentine, and Endosequence Root Repair Material in Repair of Furcation Perforations: An In Vitro Study

ABSTRACT Introduction: An in vitro comparative analysis was performed to calculate the push-out bond strength of commercially existing root repairing cements like glass ionomer cement (GIC), biodentine, mineral trioxide aggregate (MTA), and endosequence root repair material (RRM) employed in furcation perforation, with or without blood contamination present. Materials and Methods: Eighty molars were selected and subjected to furcal perforations. They were categorized based on the cement used for repair (GIC, MTA, biodentine, and endosequence RRM); furthermore, they were sub-divided into two sub-groups, that is, blood contaminated and non-contaminated. For 24 hours, all the samples were kept in an incubator till the materials were fully set. Then these samples were examined for push-out bond strength measurement. Results: The 24-hour push-out bond strength of was the highest in biodentine and the lowest in glass ionomer cement. The push-out bond strength of endosequence RRM, MTA, and GIC was influenced by blood contamination. Conclusion: The push-out bond strength of biodentine was the highest as compared to endosequence RRM, MTA angelus, and GIC. The push-out bond strength of endosequence RRM and MTA angelus after 24 hours with or without blood contamination showed insignificant differences. Group 1A (GIC contaminated with blood) displayed the least push-out bond strength among other groups.

Penambahan Bubuk Ekstrak Ikan Haruan (Channa Striata) terhadap Kekuatan Tekan dan Perubahan Warna Glass Ionomer Cement (GIC) Tipe II Secara In Vitro

This study aims to prove the effect of adding haruan fish extract powder (Channa striata) on increasing the strength of type II Glass Ionomer Cement (GIC) filling materials. The method used is a laboratory experimental method with a post-test-only control group design approach. There are 6 treatment groups, namely the addition of 10mg, 20mg, 30mg, 40mg, 50mg, and without addition (pure). This research was conducted at the Dental Materials Laboratory, Faculty of Medicine, Dentistry Study Program, Mulawarman University and PT. Sucofindo Samarinda. The study was conducted from August 2022 to March 2023. The results showed that the greatest compressive strength of glass ionomer cement (GIC) was found in pure glass ionomer cement (GIC) without the addition of haruan fish extract which showed a compressive strength value of 37.0 MPa. The more amount of haruan fish extract powder added, the lower the strength of the glass ionomer cement will be. There is a difference in compressive strength between pure glass ionomer cement (GIC) without haruan fish extract powder and glass ionomer cement (GIC) with haruan fish extract. In conclusion, Glass Ionomer Cement (GIC) type II without the addition of fish extract powder must have the greatest compressive strength compared to the addition of 10 mg, 20 mg, 30 mg, 40 mg, and 50 mg. The addition of haruan fish extract powder decreased the strength of the glass ionomer cement and no color change occurred. &#x0D; &#x0D; Keywords: Haruan Fish Extract Powder, Glass Ionomer Cement, Compressive Strength

Assessment of Occlusal Load Strength of Glass Ionomer Cement and Composite in Class V Cavities: An In-Vitro Study.

Glass ionomer cement (GIC) is widely used in dentistry due to its chemical adhesion to dental tissues, biocompatibility, and anti-cariogenic potential but they have relatively weak mechanical properties. Resin composites have been widely regarded as the first choice for direct restorations but their polymerization shrinkage has remained a major problem. It has the potential to cause tooth debonding. The composite interface leads to postoperative sensitivity, secondary caries, enamel cracks, and microleakage. A restorative material's capacity to withstand occlusal stresses and support the remaining tooth structure depends on this property. Although class V restorations are predominantly done with GIC, this study was done to compare the strength ofcomposite with the same. The GIC restore glass which is commonly used was tested against restofill composite. The main objective of conducting the study was to compare the compressive strengthof the composite vsGIC in cervical cavities. So the aimof the study isto assess the occlusal load strength of GIC and composite in class V cavities using the universal testing machine. This study was employed as an in vitro study involving 20 natural central incisor teeth without any carious lesions. Class V cavity preparation was done and the selected teeth were divided into two groups of ten each. The cavities were filled with D Tech RestoreGICand composite restorations (restofill), respectively, polished, and then subjected to testing. An eccentric load was applied to the tooth structure using an Instron (Instron E3000 Electropuls, Instron, Norwood, United States) - Universal testing machine with a cross-head speed of 1mm per minute, and the stresses were further analyzed in the presence of an occlusal loading test using a stainless steel jig of 1mm diameter which led to the sectioning of the tooth buccolingually under the applied load. An independent t-test was used to assess the results, and it was concluded that the results were statistically significant (p<0.05) at p=0.034. Conclusively, the results suggested that the occlusal load strength of the composite is greater when compared to GIC.

Effect of protective coating agents on microleakage and flexural strength of glass ionomer cement and zirconomer. an in vitro study.

The objective of this study was to assess the microleakage and flexural strength of glass ionomer cement (GIC) and modified GIC (Zirconomer) when coated with protective coating agents such as COAT-IT and G-COAT plus. Sixty tooth specimens were grouped into two groups based on the type of restorations (GIC (n = 30) and Zirconomer (n = 30)). The samples were further divided into three subgroups (n = 10) based on the protective coating agent (Petroleum jelly, G-COAT Plus, or COAT IT) applied. This study evaluated the microleakage at the occlusal and cervical margins of class V restoration after being subjected to dye penetration and sectioning. Each specimen was viewed under a 40 × microscope and was given scores based on the depth of dye penetration. They were statistically analyzed using the Kruskal-Wallis test and compared within the groups using the Mann- Whitney Test. In addition, flexural strength was assessed using standardized cuboid (25 × 2 × 2mm) specimens of restorative materials with and without protective coating agents. The mean flexural strength data of all the subgroups were statistically evaluated using a one-way analysis of variance (ANOVA) and compared within the subgroups using the student t test. A statistically significant difference was found when occlusal margin microleakage scores were evaluated with G-COAT Plus demonstrating the lowest occlusal margin microleakage when applied over GIC restoration. The increasing order of occlusal margin microleakage scores is as follows: GIC with G-COAT Plus, Zirconomer with COAT-IT, GIC with COAT-IT, GIC, Zirconomer with G-COAT Plus, and Zirconomer. However, the cervical margin microleakage scores revealed no significant difference. While flexural strength was found to be highest for the GIC group coated with G-COAT Plus, it was observed that there was a significant improvement in the flexural strength of both GIC and Zirconomer when coated with either of the protective coating agents. Within the limitations of this in vitro study, it was observed that the application of protective coating agents can significantly reduce the potential microleakage and improve the flexural strength of the restorative material especially when zirconia-reinforced GIC is the restorative material.

Comparative Evaluation of Mechanical Properties and Bond Strength of Glass Ionomer Cement reinforced with three different concentrations of Silver Nanoparticles as against Conventional Glass Ionomer Cement in Primary Teeth.

Introduction: Restorative dental materials are defined as substances that are used to repair, replace, or enhance a patient's teeth. Various materials used in paediatric dentistry are zinc oxide eugenol, glass ionomer cement, resin composite, calcium hydroxide, silver amalgam, giomers etc. GIC is a biocompatible material having a low thermal expansion coefficient and fluoride release property. There are still a few drawbacks of GIC due of their poor mechanical properties therefore addition of Silver Nanoparticles demonstrated improved mechanical and bactericidal capabilities. There hasn't been much study on the quality of the bond contact between silver nanoparticles and dentin, as well as the color's durability. Aim: To evaluate and compare the mechanical properties and bond strength of Glass ionomer cement reinforced with three different concentrations of silver nanoparticle as against conventional glass ionomer cement in primary Teeth. Materials and Method: Silver nanoparticles will be prepared using three chemicals namely, silver nitrate, sodium citrate and tannic acid. Traditional GIC (GC Fuji II, GC Corporation, Tokyo, Japan) will be purchased. Three different concentrations of silver nanoparticles will be prepared i.e., 0.2, 0.4, and 0.6%. The GIC specimens will then be divided into 4 groups: GIC without silver nanoparticles (AgNPs),0.2%,0.4% and 0.6% AgNPs. Mechanical properties will be checked such as compressive, tensile, and bond strength using Universal Testing Machine. Expected Results: GIC reinforced with silver nano particles is expected to have better mechanical strength, less microleakage and wear resistance, greater fracture resistance and adhesive bond strength. Conclusion: GIC reinforced with silver nano particles will be expected to have better mechanical and physical properties than conventional Type II GICs and is expected to be a promising material for restoration in primary teeth.

Effectiveness Of Green Nanochitosaan Addition On Compressive Strength Of Glass Ionomer Cement

Glass ionomer cement is a restorative material that is adhesive, tooth-colored, and has the ability to release fluoride ions which are affected by the degree of acidity (pH). Apart from that, one way to utilize the waste from green mussels is by processing them into chitin and chitosan as materials to strengthen the properties of glass ionomer cement. Glass ionomer cement contains materials such as powderacid soluable calcium fluoraluminosilicate glass and liquidaqueous solution of polyacrylic acid. This can be an alternative as a treatment for dental caries. Objective: This study aims to determine the effectiveness of the addition of green mussel shell (perna viridis) nanochitosan on the compressive strength of glass ionomer cement. Method: This study used a quantitative experimental laboratory study with a True Experimental study design using a post test only control group design. the total sample used was 25 samples. Results: The 2% nanochitosan concentration has the highest compressive strength value compared to other concentrations, as evidenced by the mean value at 2% concentration, which is 4.10 MPa. Conclusion: The result of 2% green mussel (perna viridis) nanochitosan was the most effective treatment in influencing the compressive strength of glass ionomer cement. The greater the concentration used, the higher the compressive strength of the resulting glass ionomer cement.

Phytic Acid: A Novel Dentine Conditioning Agent for Glass Ionomer Cement Restorations: An In Vitro Scanning Electron Microscopic Study.

Various dentin conditioners have been recommended to enhance the bond strength of glass ionomer cement (GIC) to dentin. The purpose of the in vitro study was to determine the efficacy of three dentin conditioners on the microshear bond strength of GIC and the failure patterns of the restoration, as well as the efficacy of removing the smear layer using a scanning electron microscope (SEM). Eighty healthy mandibular premolars were cleaned, isolated, and divided into four groups (n = 20). Flat coronal dentinal surfaces were accomplished by removing the occlusal surface of the crowns. Each group received the following treatment: group 1 with 10% polyacrylic acid; group 2 with 10% ethylenediaminetetraacetic acid (EDTA); group 3 with 1% phytic acid; and group 4 with no conditioning (control). High-strength Fuji IX GIC was applied to the dentin, and samples were thermocycled and de-bonded with a crosshead speed of 0.5 mm/min employing a shear force. A stereomicroscope and a SEM were used to examine the dentin surface at magnifications of 2000× and 5000×. One-way analysis of variance (ANOVA), Tukey's post hoc test, and Chi-squared test were used to assess data on microshear bond strength, smear layer removal, and failure modes. The bond strength of group 4 was statistically highly significant (P ≤ 0.001) compared to the other groups. However, the differences between groups 2 and 3 were insignificant. Mixed pattern of failure was the least in group 3 (IP6). In group 3, the SEM photomicrograph revealed open dentinal tubules with complete removal of the smear layer. The results of the present study affirm that phytic acid enhances the bond strength of GIC restorations and removal of smear layer to a level comparable to EDTA as a dentin conditioner.

Comparative Evaluation of Microleakage and Shear Bond Strength of Glass Ionomer Cement, Composite, Resin Modified Glass Ionomer Cement Restorative Material: An In Vitro Study

Aim: Evaluation of microleakage and shear bond strength of glass ionomer cement, composite, resin modified glass ionomer Cement Restorative Material. Material and Method: Thirty freshly extracted non carious teeth, free of cracks and restorations, collected for the present in-vitro study. Teeth were divided in three equal group i.e. group A: Glass Ionomer Cement. Group B: Resin Modified Glass Ionomer Cement, Group C: Composite Resin. All groups' shear bond strengths were evaluated using a universal testing machine. A rod in the shape of a chisel was positioned close to the bonded restorative material and directly next to the flat dentinal surface. To debond the material, a cross head of universal testing machine at a speed of 0.5mm/min was employed. Then, Mega Pascal Units (MPa) were used to calculate the shear bond strength. To evaluate the microleakage two coats of nail polish were applied to the samples, leaving a 1 mm window around the cavity boundaries. A wet cotton pellet was placed over the restoration to avoid desiccation while the nail polish was being applied. Inverted teeth were submerged for 24 hours at 37°C under vacuum in a solution of 2% Rhodamine-B dye. Only the coronal part of the teeth were dyed to avoid dye leakage via the root apices. The surface-adhered dye was washed off the specimens in tap water after removing them from the dye solution, and nail polish was then removed with a BP blade. The teeth were sectioned longitudinally in a bucco-lingual direction through the center of the restorations using a water-cooled low-speed diamond disc. The section with the greater leakage was evaluated with a stereomicroscope at ×25 magnification to determine the extent of dye penetration at the occlusal and gingival margins by two evaluators who were blinded to the experimental groups. Result: Composite resin showed highest shear bond strength followed by Bond Strength of Resin Modified Glass Ionomer Cement and least with conventional glass ionomer cement. Microleakage was found lower in composite resin as compared to Resin modified glass ionomer cement and glass ionomer cement. Conclusion: It can be stated that Composite resin and Resin modified glass ionomer cement have good shear bond strength and lower microleakage as compared to Glass Ionomer Cement.

Comparative Evaluation of Shear Bond Strength of Glass Ionomer Cement, Composite and Compomer in Primary Teeth: An In Vitro Study

Background: Because the main dislodging pressures at the tooth restoration interface have a shearing effect, shear bond strength is crucial for the restorative material clinically. Therefore, greater shear bond strength suggests improved material to tooth bonding. Glass ionomer cement and composite is the most popularly used restorative material. Composite resins have better mechanical properties and esthetics than many other types of cement, but they need bonding agents as they are hydrophobic and hence fail to adhere to the teeth. Compomers are polyacid modified resin composites. Compomer and composite resin have similar physical properties, as they are thought to bond to dentin by micromechanical bonding. As resin composites are used in this, the polymerized acid monomer shows acidity when it comes in contact with the saliva and there is a reaction of fluoride-containing basic glass resulting in the cariostatic effect. Aim: The purpose of this study was to evaluate and compare the shear bond strength of Glass Ionomer Cement (Fuji IX GP), Composite Resin (Filtek Z-250) and Compomer, (Compoglass, Ivoclar). Material and Method: An in-vitro, experimental study was conducted on 30 freshly extracted over-retained deciduous molars. Samples were randomly divided into three groups depending on the material to be used. Flat dentinal surface on tooth was prepared over which restorative materials were placed. The prepared specimen was subjected to shear test and the value obtained was compared. Descriptive statistical analysis was performed to calculate the mean shear bond strength of each group. Result: It was observed from the study that the composite resin had the highest shear bond strength value (17.13 ± 1.54), followed by compomer (11.32 ± 1.05) whereas GIC showed the least shear bond strength (6.56 ± 0.87). Conclusion: It was concluded that composite restorative materials show higher shear bond strength than glass ionomer cement and compomer in primary molars, but shear bond strength of compomer was higher than that of glass ionomer cement.

Evaluation of the Effect of Nanoparticle Graphene Oxide on Flexural Strength of Glass Ionomer Cements.

Glass ionomer (GIC) is a widely used restorative material in dentistry, but it has relatively weak mechanical properties. In this research, the effect of graphene oxide (GO) on the flexural strength of GIC was investigated. In this experimental study, 60 GIC samples in 6 groups of 10 were prepared, including Group 1: control conventional glass ionomer (CGIC), Group 2: CGIC + 1% wt of GO, Group 3: CGIC + 2% wt of GO, Group 4: control resin-modified glass ionomer (RMGI), Group 5: RMGI + 1% wt of GO, and Group 6: RMGI + 2% wt of GO. The samples were kept for 24 hours. The flexural strength of the samples was measured by using a universal testing machine. Data were analyzed by two-way ANOVA and posthoc Tukey test. (P < 0.05). In the RMGI groups, the mean flexural strength value of the RMGI + 2% GO group was significantly higher than that of the RMGI control group (P=0.027). In the comparison of RMGI groups with their corresponding CGIC groups, the mean flexural strength values of all RMGI groups were significantly more than CGIC groups (P < 0.001). RMGI + 1% GO was not significantly different from control RMGI and RMGI + 2% GO (P=0.802, P=0.395, respectively). There was no significant difference between CGIC groups. Adding 2% by weight of GO to RMGI increases the flexural strength of RMGI, which could be of great importance in clinical practice in order to reinforce the mechanical properties of this dental material. The flexural strength of RMGI is higher than that of CGIC.

Evaluation of the effect of diode laser activation on push-out bond strength of different intraorifice barriers in endodontically treated teeth. An in-vitro study

Introduction: The placement of intraorifice barriers should facilitate proper adhesion; however, it is still a challenge with existing intraorifice barrier materials. Thus, this study aims to evaluate the push-out bond strength of Glass Ionomer Cement (GIC), Tetric-N-Flow, and Biodentine as intraorifice barriers with and without diode laser activation. Materials and Methods: Human-extracted single-rooted 60 mandibular premolars were decoronated to standardize 13 mm root length. Root canal was instrumented with rotary ProTaper universal system till F4 and alternatively irrigated with 5 ml of 2.5% sodium hypochlorite and normal saline, followed by obturation using gutta-percha and AH-plus sealer. About 3.5 mm of gutta-percha was removed from the orifice using peso reamer. Horizontal tooth sections of 3.5 mm in length were obtained from the coronal third of each sample and were randomly divided into three groups (n = 20 each) for intraorifice barrier materials. Group 1: GIC; group 2: Tetric-N-Flow and group 3:Biodentine. Each group was further subdivided into two subgroups A and B (n = 10 each) with and without diode laser. After 7 days, the specimens were mounted in acrylic molds and push-out bond strength was evaluated under universal testing machine. Data analysis was done using One way-analysis of variance and post hoc Tuckey comparison tests (P ≤ 0.05). Results: Laser activation in each group showed greater push-out bond strength; however, Biodentine with laser (group 3A) exhibited higher bond strength compared to all groups (P ≤ 0.05). Conclusion: Biodentine with laser activation before placement of the coronal barrier of endodontic treated tooth increases the quality of bond strength.

In vitro evaluation of the compressive strength of glass ionomer cement modified with propolis in different proportions

Background: Antibacterial additives are frequently added in an effort to enhance the antibacterial properties of glass ionomer cement (GIC). GIC modified with ethanolic extract of propolis (EEP) has been proven to improve GIC’s antibacterial properties, but this modification is suspected to have detrimental impacts on its compressive strength. Objectives: To evaluate the compressive strength of GIC incorporated with different proportions of propolis extracts from Trigona spp. from Garut, Indonesia. Methods: This experimental in vitro laboratory study comsisted of 20 cylindrical glass ionomer specimens divided into four groups according to the proportions of propolis added to the GIC liquid: Group A: conventional GIC (control), Group B: 25% EEP added (% w/w), Group C: 30% EEP added (% w/w), and Group D: 35% EEP added (% w/w). A universal testing machine was used to assess compressive strength after the samples were immersed in artificial saliva and incubated for 24 h. Data were analyzed with one-way analysis of variance and Tukey’s test (P < 0.05). Results: The addition of EEP decreased the compressive strength of the GIC liner. Mean compressive strength values were 118.06 ± 24.1 MPa (Group A), 103.17 ± 10.26 MPa (Group B), 79.18 ± 9.99 MPa (Group C), and 77.03 ± 6.13 MPa (Group D). In comparison to the control group, a nonsignificant difference was observed when 25% EEP was added (P > 0.05), whereas both 30% EEP and 35% EEP resulted in significant decreases in compressive strength (P < 0.05). Conclusion: GIC modified with 25% EEP might be a promising restorative material for cavity linings.

Evaluation of flexural strength of glass ionomer cement after immersion in fruit juices.

Glass ionomer cement (GIC) is a material used for restoration in dentistry. The stress in a material right before it yields in a flexure test is referred to as flexural strength. The aim of this study was to evaluate the flexural strength of two different glass ionomers after immersion in fruit juices. Five samples of D-Tech and Shofu GIC were prepared from each for the in vitro study. The eight samples were subjected to a flexural strength process and two were left as control which was followed by the determination of maximum force and displacement, then the collected data were used to determine flexural strength and analyzed using SPSS software (IBM SPSS Statistics for Windows, Version 22.0. Armonk, NY: IBM Corp). The mean value of flexural strength of the D-Tech GIC immersed in fruit juices is 4.4375 and the mean value of Shofu GIC immersed in fruit juices was 8.4975. Paired t-test was done between the two groups and the P value was 0.00, which is considered highly statistically significant. From this study, it is evident that the GIC brand Shofu has higher flexural strength compared to D-Tech. Flexural strength was decreased for both the GIC groups when immersed in grape juice.

Evaluation of Micro-shear Bond Strength of Glass Ionomer Cement to Silver Diamine Fluoride Treated Artificial Dentinal Caries

Evaluation of Micro-shear Bond Strength of Glass Ionomer Cement to Silver Diamine Fluoride Treated Artificial Dentinal Caries

SMART: Silver diamine fluoride reduces microtensile bond strength of glass ionomer cement to sound and artificial caries-affected dentin.

Silver-modified atraumatic restorative technique (SMART) is an emerging restorative technique; however, the effect of silver diamine fluoride (SDF) application on the bond strength of glass ionomer cement (GIC) is unknown. This study aimed to determine if SDF application to sound and artificial caries-affected dentin (ACAD) immediately prior to GIC restoration affected microtensile bond strength (µTBS). Caries was induced on extracted molars using a pH-cycling protocol that was validated against natural caries (similar µTBS). Dentin surfaces were treated with 38% SDF, control groups with de-ionized water and immediately restored. Beam-shaped specimens were sectioned and subjected to tensile forces for µTBS determination. Two hundred and eighty-seven specimens from 40 teeth were tested. SDF application significantly (p<0.001) reduced µTBS in sound dentin (19.00±8.20 MPa vs. 14.60±6.68 MPa), while no difference was found in ACAD. No difference was found in failure mode among groups. For SMART, SDF application on sound dentin before immediate GIC restoration may decrease bond strength.

Effect of Hydroxyapatite Synthesized from Tilapia Fish Scale Waste on the Shear Bond Strength of GIC and RMGIC to Enamel Layer (&lt;i&gt;In Vitro&lt;/i&gt; Study)

Indonesia is a country that has many types of freshwater fish, one of which is tilapia. The consumption of tilapia among the people of Indonesia is quite high. So that, it will produce a lot of fish scale waste. Fish scales can be used as a natural source of hydroxyapatite because they contain calcium. The aim of this study was to evaluate the effect of hydroxyapatite synthesized from tilapia fish scale (Oreochromis niloticus) on the shear bond strength of glass ionomer cement and resin modified glass ionomer cement to enamel layer. Hydroxyapatite was synthesized from tilapia fish scale (Oreochromis niloticus) by calcination method at 800°C. Sample was made from glass ionomer cement (GIC) and resin modified glass ionomer cement (RMGIC) combined with 2, 5 and 8%wt of hydroxyapatite, respectively. Sample was bonded to enamel layer of human premolar tooth. The shear bond strength of sample was tested by using Universal Testing Machine. The result showed that shear bond strength were increased for higher concentration of hydroxyapatite that added to glass ionomer cement or resin modified glass ionomer cement. The maximum of shear bond strength of GIC Group is 6,38 ± 0,05MPa after 8%wt hydroxyapatite addition. The maximum of shear bond strength of RMGIC Group is 6,59 ± 0,06 MPa after 8%wt hydroxyapatite addition. There were significance differences among all group tested (p &lt;0.05). It can be concluded that hydroxyapatite synthesized from tylapia fish scale can increase the shear bond strength of glass ionomer cement and resin modified glass ionomer cement.

Effect of Nanofilled Resin-Based Coating on the Compressive Strength of Glass Ionomer Cement – in vitro

Glass ionomer cement as one of the restoration materials requires high compressive strength so it can last during functional activity. The latest glass ionomer cement comes with glass hybrid technology and a nanofilled resin-based protective coating which is said to increase the compressive strength of glass ionomer cement. The aim of this study was to analyze the effect of nanofilled resin-based coating and the types of glass ionomer cement materials on their compressive strength. Two types of commercial glass ionomer cement material were used; conventional (Fuji IX GP Extra), and hybrid (EQUIA Forte Fill) glass ionomer cement. Forty cylindrical (4 x 6 mm) samples were prepared in each group. The main group was divided into 4 subgroups (n=10) based on the protective coating used (EQUIA Forte Coat, Varnish, Control, Water + EQUIA Forte Coat). Eight subgroups were immersed in 37 °C distilled water for 7 days, then a compressive strength test was performed using a universal testing machine. The data analysis showed no significant difference in the compressive strength between the two types of glass ionomer cement materials (p&gt;0.05). The use of a protective coating was associated with a significant decrease in the compressive strength (p&lt;0.05). The use of glass ionomer cement without the application of a protective coating was considered to be quite good because the compressive strength value of the restoration still met the standards of the American Dental Association.

Shear Bond Strength of Glass Ionomer Cement to Er, Cr:YSGG Laser-irradiated Dentin in Primary Teeth: An In Vitro Study.

The clinical success of restorative materials depends upon a good adhesion with the dentinal surface to resist various dislodging forces acting within the oral cavity. Shear bond strength is the resistance to forces that slides restorative material past tooth structure. The Er, Cr:YSGG pulsed laser irradiation may be used to prepare enamel, dentin, cementum, and bone effectively and cleanly without leaving a smear layer. To compare the shear bond strength of GIC to dentin treated with conventional cavity conditioning and laser irradiation methods. Thirty samples of noncarious human primary molars which get exfoliated either due to physiologic reasons or extracted due to any therapeutic reasons were collected for the study. Occlusal enamel was removed and teeth were then embedded in self-cured acrylic mold. All the prepared specimens were disinfected with Chloramine T solution and stored in distilled water for 24 hours at room temperature and teeth were randomly divided into the following groups; group 1: conventional cavity conditioning and type IX GIC restoration, group 2: Er, Cr:YSGG conditioning and type IX GIC restoration. Specimens were then subjected to thermocycling and shear bond strength was evaluated using the Lloyd testing machine. One-way ANOVA test followed by Tukey's HSD post hoc analysis was used to compare mean shear bond strength between two study groups. The level of significance [p-value] were set at p < 0.05. Conditioning the dentin surface with Er, Cr:YSGG laser can increase the shear bond strength of glass ionomer restoration than conventional cavity conditioning. Chikkanarasaiah N, P H. Shear Bond Strength of Glass Ionomer Cement to Er, Cr:YSGG Laser-irradiated Dentin in Primary Teeth: An In Vitro Study. Int J Clin Pediatr Dent 2022;15(2):199-203.

Effect of silver diamine fluoride, potassium iodide, and glutathione on micro-shear bond strength of glass ionomer cement to caries affected dentine.

Silver diamine fluoride (SDF, 38%) is an efficient topical fluoride used to arrest dental caries though it causes black staining of both teeth and restoration. The application of potassium iodide (KI) after SDF reduces the stain, but the color change is only temporary. An alternative method suggested is by mixing glutathione (GSH) with SDF, which preserves the silver ions of SDF within the solution. Hence, the purpose of this in vitro study was to evaluate the microshear bond strength (μSBS) of glass ionomer cement (GIC) to caries affected dentin (CAD) pretreated with SDF/KI/GSH. Thirty dentine slices of 2 mm thickness from human permanent upper premolars were demineralized using pH cycling method to mimic CAD. They were allocated to three groups of 10 each and treated with SDF, SDF-KI (SDF followed by KI), SDF + GSH (SDF mixed with GSH), respectively. Specimens were bonded with GICs. The μSBS was assessed using a universal testing machine and the data obtained were analyzed using one-way ANOVA and Tukey's post hoc test. The μSBS (mean ± standard deviation) values for groups SDF, SDF-KI, and SDF + GSH were 4.81 ± 2.026, 5.78 ± 1.809, 8.18 ± 2.828 megapascal respectively. Group 3 showed significantly better bond strength compared to groups 1 and 2. In group 2, the addition of KI showed better bond strength when compared to group 1, but the difference was not statistically significant. Pretreatment of teeth with GSH along with SDF application showed significantly better bond strength of GIC to CAD compared to SDF and SDF-KI.