Hardness Of Composite Resin Research Articles

Effect of Pempek Vinegar on Composite Resin Hardness Nanohybrid

Background: Nanohybrid composite resin is a dental restorative material that is widely used in modern dental practice. However, the interaction of these materials with acidic foods and drinks, such as pempek vinegar, can affect their mechanical properties. Materials and Methods: This research is laboratory experimental research with pretest-posttest with only group design. In this study, nanohybrid composite resin was used in the form of a circle on a mold with a thickness of 2 mm and a diameter of 10 mm which was immersed in a solution of pempek vinegar. The number of samples used is 6 samples with 4 test groups. The 4 test groups were divided into immersion times of 1,3,5,7 days. Results: After immersion, the results of the hardness of the composite resin were taken. Using the normality and homogeneity tests, the hardness test results data were processed. It was found that the data were normally distributed and not homogeneous for each data group. After that an analysis was carried out using independent t-test (p <0.005) it was found that there was a significant effect of the hardness of the composite resin on immersion in Pempek vinegar solution which was soaked for 3 days, 5 days and 7 days. Conclusion: Pempek vinegar solution affects the surface hardness of the nanohybrid composite resin which is probably influenced by pH, liquid absorption ability, and soaking time.

Influence of the Loading with Newly Green Silver Nanoparticles Synthesized Using Equisetum sylvaticum on the Antibacterial Activity and Surface Hardness of a Composite Resin.

The aim of the study was to evaluate the antibacterial activity and surface hardness of a light-activated microhybrid composite resin modified with green silver nanoparticles (AgNPs). AgNPs were synthesized using an Equisetum sylvaticum extract and characterized through different methods such as UV-Vis, EDX, and FTIR. The obtained AgNPs were mixed with a microhybrid composite resin (Herculite XRV, Kerr Corp., Orange, CA, USA) in different concentrations: 0% (group A-control); 0.5% (group B); 1% (group C); and 1.5% (group D). A total of 120 composite resin disk-shaped samples were obtained and divided into 4 groups (n = 30) according to AgNP concentration. Each group was then divided into 2 subgroups: subgroup 1-samples were not soaked in 0.01 M NaOH solution; and subgroup 2-samples were soaked in 0.01 M NaOH solution. The antibacterial activity against Streptococcus mutans was determined using a direct contact test. A digital electronic hardness tester was used to determine the composite resin's Vickers surface hardness (VH). Statistical analysis was performed using the Mann-Whitney U and Kruskal-Wallis nonparametric tests with a confidence level of 95%. Groups C and D showed higher antibacterial activity against S. mutans when compared to the control group (p < 0.05). No significant differences were recorded between VH values (p > 0.05). The use of AgNPs synthesized from Equisetum sylvaticum as a composite resin filler in 1% wt. and 1.5% wt. reduced the activity of Streptococcus mutans. Soaking of the experimental composite resin decreased the antibacterial efficacy. The loading of a microhybrid composite resin with AgNPs in concentrations of 0.5% wt., 1% wt., and 1.5% wt. did not influence the surface hardness.

The Effect of 1% Povidone Iodine Mouthwash on The Surface Roughness of Zirconia Reinforced Glass Ionomer Cement

&#x0D; Introduction: Zirconia reinforced glass ionomer cement is a new generation glass ionomer cement restoration material with the addition of zirconia nanoparticles that is equivalent in strength to amalgam while maintaining ability to release fluoride like conventional glass ionomer cements. Surface roughness can be affected by various factors including the use of mouthwash. Mouthwash that is commonly used during pandemic COVID-19 is 1% povidone iodine. Previous study stated that povidone iodine mouthwash contains alcohol and acidic pH which can decrease the hardness of composite resins. Objective: To determine the effect of 1% povidone iodine mouthwash on the surface roughness of zirconia reinforced glass ionomer cement. Methods: This was a true experimental laboratory research with a pre test and post test control group design. The research samples consisted of 36 samples of zirconia reinforced glass ionomer cement with diameter of 10 mm and height of 2 mm. The samples were divided into two groups: the control group which was immersed in artificial saliva and the treatment group which was immersed in 1% povidone iodine mouthwash for 24 hours. Surface roughness was measured using a surface roughness tester. Data were analyzed using Paired Sample T-Test and Independent Sample T-Test. Results: Paired Sample T-test results showed no significant difference in the surface roughness of the control group between before and after immersion with p value = 0,074 (p&gt;0,05) and a significant difference in the surface roughness of the treatment group between before and after immersion with p value = 0,000 (p&lt;0,05). Independent Sample T-Test results showed significant difference in the surface roughness between the control group and the treatment group with p value = 0,000 (p &lt;0.05). Conclusion: 1% povidone iodine mouthwash has an effect on increasing the surface roughness of zirconia reinforced glass ionomer cement.

THE EFFECT OF GLYCERIN APPLICATION ON SURFACE HARDNESS OF NANOHYBRID COMPOSITE RESIN IMMERSED IN ALCOHOLIC MOUTHWASH

ABSTRACT Background: Composite resin is the most commonly used restorative material. One of properties composite resins is surface hardness can change due to exposure of the restorative material to oral fluids such as alcoholic mouthwash. The degradation that occurs due to alcoholic mouthwash is able to reduce the surface hardness of the nanohybrid composite resin. Glycerin is able to increase the hardness of the composite resin by perfecting the polymerization that occurs in the restorative material when exposed to light cured light. Objectives: This study aims to determine the effect of glycerin application on the hardness of nanohybrid composite resins after immersion in alcoholic mouthwash. Methods: A total of 32 samples of nanohobride composite resin in this study were made in the form of a cylinder with a diameter of 5 mm and a thickness of 2 mm. The nanohybrid composite resin samples were divided into control and treatment group by applying glycerin on the sample surface before light curing. The study was continued by immersing the sample into artificial saliva for 24 hours and alcoholic mouthwash for 6 hours. The research continued with surface hardness test using the Vickers Hardness Tester. Result : Paired bivariate T test showed a significant difference between the two groups (p&lt;0.005). The conclusions of this study indicate that the application of glycerin has an effect on the hardness of the nanohybrid composite resin after immersion with alcoholic mouthwash. Conclusion: The application of glycerin affects the hardness of the nanohybrid composite resin after immersion with alcoholic mouthwash. Key words: Glycerin application, Hardness, Nanohybrid composite resin

Impact of Nanoparticles Additions on the Strength of Dental Composite Resin.

Objective This study aimed to evaluate the effect of nanoparticles, zirconium dioxide (ZrO2), titanium dioxide (TiO2), and silicon dioxide (SiO2), on flexural strength (FS), hardness, and wear resistance of light cured dental composite resin. Materials and Methods 210 rectangular and disc-shaped composite resin specimens were fabricated with dimensions (25 × 2 × 2 ± 0.03 mm) and (6×4 ± 0.03 mm) for FS, hardness, and wear resistance, respectively (70/test). Specimens of each test were divided according to nanofillers into four groups, unmodified as control, ZrO2 (Z), TiO2 (T), and SiO2 (S) groups; each one was further subdivided into two subgroups according to nanoparticles concentration, 3wt.% and 7wt.% (Z3, Z7, T3, T7, S3, and S7), 10 specimens of each subgroup. A3-point bending test and Vickers hardness test were used for FS and hardness measurements, respectively. Wear resistance was evaluated by the differences in surface roughness of tested specimens before and after wear test. Two-way and 1-way ANOVA and Bonferroni's post hoc tests were done for data analysis (α = 0.05). Results Two-way ANOVA for FS and wear resistance showed that there was a significant interaction between type of nanoparticles and concentration of nanoparticles (p < 0.001) while two-way ANOVA for hardness showed that both type of nanoparticles and concentration of nanoparticles had a significant effect (p < 0.001), while the effect of their interaction was not statistically significant (p=0.142). 1-way-ANOVA test showed significant increase in FS and wear resistance for all tested groups (p < 0.001 and p < 0.001, respectively) except T7 and S7. Also, there was a significant enhancement in hardness for all tested groups (p < 0.001). Conclusion Modification of light cured composite resin with certain amounts of nanoparticles (3% and 7% of ZrO2 and 3% of TiO2 and SiO2) can be beneficial in improving flexural strength and wear resistance while hardness of composite resin was increased with all NPs additions.

The Effect of Espresso and Drip Brewing Coffee Methode to The Hardness of Bulk-Fill Composite Resin

Background: The most restoration material used currently in dentistry was composite resin. The newest generation of composite resin was bulk-fill composite resin. The bulk-fill composite resin had advantages of lower polymerization contraction and a more straightforward and faster restoration technique. One of the factors which could affect the hardness of composite resin was the consumption of acidic drinks. The acidic beverage that people often consumed is coffee. A few coffee brewing methods were espresso and drip brewing.Objective: This research aimed to identify the effects of coffee soaking through espresso and drip brewing methods on bulk-fill composite resin's hardness.Methods: his research was experimental research, with a post-test control group design and a total sample of 27 samples. The soaking process was taken for seven days at a temperature of 37˚C on artificial saliva, espresso, and drip brewing coffee methods. The hardness of bulk-fill composite resin was measured after seven days by using Vickers hardness. The statistic test exerted One-Way ANOVA.Results: This research found a significant difference in bulk-fill composite resin's hardness among all groups, p-value = 0.00 (p&lt;0.05). The result of the post-hoc LSD test showed a significant difference in the change of bulk-fill composite resin hardness between the artificial saliva group and espresso group (p=0,00) and no significant difference found between the artificial saliva group and drip brewing group (p=0.85).Conclusion: Soaking with espresso coffee has the smallest hardness value compared to soaking with drip brewing coffee and artificial saliva, so soaking with espresso coffee is the most influential on the hardness of the bulk fill composite resin.

Air Pollution Exposure Duration and Its Correlation with Triglyceride, HDL, and Atherogenic Index in Online Motorcycle Drivers

Background: The most restoration material used currently in dentistry was composite resin. The newest generation of composite resin was bulk-fill composite resin. The bulk-fill composite resin had advantages of lower polymerization contraction and a more straightforward and faster restoration technique. One of the factors which could affect the hardness of composite resin was the consumption of acidic drinks. The acidic beverage that people often consumed is coffee. A few coffee brewing methods were espresso and drip brewing.Objective: This research aimed to identify the effects of coffee soaking through espresso and drip brewing methods on bulk-fill composite resin's hardness.Methods: his research was experimental research, with a post-test control group design and a total sample of 27 samples. The soaking process was taken for seven days at a temperature of 37˚C on artificial saliva, espresso, and drip brewing coffee methods. The hardness of bulk-fill composite resin was measured after seven days by using Vickers hardness. The statistic test exerted One-Way ANOVA.Results: This research found a significant difference in bulk-fill composite resin's hardness among all groups, p-value = 0.00 (p&lt;0.05). The result of the post-hoc LSD test showed a significant difference in the change of bulk-fill composite resin hardness between the artificial saliva group and espresso group (p=0,00) and no significant difference found between the artificial saliva group and drip brewing group (p=0.85).Conclusion: Soaking with espresso coffee has the smallest hardness value compared to soaking with drip brewing coffee and artificial saliva, so soaking with espresso coffee is the most influential on the hardness of the bulk fill composite resin.

The Effect of Carbonated, Isotonic, and Yoghurt Drinks to the Hardness of Bulk Fill Composite Resin

Background: Composite resin often used as a restoration material due to its advantages in the aesthetic field. The bulk-fill type is one of the composite resin that can be applied directly into cavities as deep as 4 mm, so that restoration procedure becomes easy and effective. Hence, exposure to various acidic drinks can reduce the hardness of composite resins and eventually lead to failure of the tooth restoration process.Objective: This research aimed to evaluate the effects of several commercial acidic drinks, (carbonated, isotonic, and yogurt) on the hardness of bulk-fill composite resins.Method: This research was an experimental study with a post-test control group design. Twenty-four specimens were made with the size 10 x 4 mm using the metal mold rings. Specimens were divided into 4 groups for artificial saliva (served as a control), carbonated, isotonic, and yogurt. Specimens were immersed in storage agents for 5 seconds followed by artificial saliva for 5 seconds. This cycle was repeated 20 times for 14 days. The bulk-fill composite resin hardness was measured using a Micro Vickers Hardness Tester with a load of 100 grams for 10 seconds. Statistical analysis was performed using One Way ANOVA and Post Hoc LSDResults: Data were normally distributed and homogeneous with p &gt; 0.05. The One Way ANOVA test showed the biggest difference in bulk fill composite resin between 4 groups (p &lt; 0.001). The Post Hoc LSD test showed significant differences between all groups (p &lt; 0.001)Conclusion: Carbonated, isotonic, and yogurt drink significantly decreased surface microhardness of bulk-fill composites resin but the carbonated drinks greatly reduce the hardness value since it has the lowest pH of 2.3.

Benefit of Glycerine on Surface Hardness of Hybrid &amp; Nanofill Resin Composite

Background: Composite resins restoration is a treatment for tooth structure loss due to pathological conditions. Longevity of composite resins restoration can be affected by surface hardness restoration. Glycerin can increase surface hardness restoration with inhibit bond oxygen and free radicals on polymerization composite resins. Purpose: Analyze the increase surface hardness composite resins restoration after glycerin application before light-curing composite resins. Review(s): Of the six journals included in this literature review, five journals reported significant differences because of the obstacles in the polymerization process of the composite resin when composite contact with light-curing will activate the photoinitiator to produce highly reactive free radicals, free radicals will break the double chain carbon bonds of monomers and form single bonds of free radicals with monomers. Bonding of free radicals with monomers will produce polymeric bonds (degree of conversion) which affects the level of surface hardness of the filling. While one journal noted no significant difference in the surface hardness of composite resin after glycerin application. Conclusion: The use of glycerin before light-curing can increase the surface hardness composite resin restorations.

Comparison Of The Effect Of Acid Type Of Cuko Pempek On The Surface Hardness Of Mycrohybrid And Nanohybrid Composite Resin

Abstract often used nowadays because of the combination of filler with good aesthetic and mechanical strength. Various factors in the oral cavity such as acid solution can affect the surface hardness of composite resin. Cuko pempek is an additional sauce that served which has acidic pH. This study aimed to compare the effect of acid type of cuko pempekhardness of microhybrid and nanohybrid composite. Materials and Methods:Thirty-six samples of microhybrid (n=18) and nanohybrid composite (n=18) with 5 mm in diameter and 2 mm in thickness were immersed in three different solutions: artificial saliva (control), cuko pempek using vinegar, and cuko pempekSurface hardness was measured before and after immersion using Vickers Hardness Tester. Resultsshowed a significant difference on the surface hardness of composite resin before and after ardness of microhybrid and nanohybrid composites after (p&lt;0,0167) showed statistically significant differences, while there were no cuko pempek using vinegar and tamarind (p&gt;0,0167). This study alsothat there were significant differences on the surface hardness of microhybrid and nanohybrid composite after cuko pempek using vinegar, and cuko pempek using tamarind (p&lt;0,05). face hardness of nanohybrid composite was lower than microhybrid composite after using vinegar and tamarind. composite resin, surface hardness.

PERENDAMAN DENGAN PERASAN BUAH JERUK LEMON (Citrus lemon) DAPAT MENURUNKAN KEKERASAN RESIN KOMPOSIT NANOHYBRID

Composite resin is a restoration material that is often used because the composite resin has good aesthetic value like mimetic the teeth color. Composite resins have a physical and mechanical condition. One of the mechanical condition is hardness. The surface hardness of composite resins is the surface resistance of the composite resin material to the applied pressure. One of the factors influencing composite hardness is the food and beverages consumed. Consuming acidic drinks continuously for a long time period can erode composite resin filling. The purpose of this study was to determine the effect of soaking into a citrus lemon on the hardness of nanohybrid composite resin. This type of research was true experimental with pre-test post-test with control group design using 24 composite resin samples which are divided into 4 groups with 6 samples each. The groups in this study were nanohybrid composite resins soaked with citrus lemon and aqua dest for 60 minutes and 120 minutes. The hardness tested using a Vicker hardness tester. The results of the study using the LSD (Least Significant Difference) test showed that the significance value of p= 0.014 (p&lt;0.05), which means that the use of citrus lemon for 120 minutes affected the hardness of nanohybrid composite resin. In conclusion, soaking with citrus lemon for 120 minutes reduces more the hardness of nanohybrid composite resin compared with soaking for 60 minutes.

Pengaruh Aplikasi Gliserin pada Kekerasan Resin Komposit Nanofiller dengan Perendaman Cuka Apel

Composite resin is a type of filling material that is often used because it has good bonds with dentine and enamel and has a high aesthetic value. Nanofiller composite resin has high hardness, good polishing, color accuracy, and good translucency. The hardness of composite resins can change caused by low pH beverage. Purpose: To determine the differences in effect of glycerin application on hardness of nanofiller composite resins with immersion of apple cider vinegar. The type of research used was experimental laboratories with a pretest and post test group design. Samples were 24 immersion in apple vinegar for 60 and 120 minutes. Measurement of hardness using the Vicker Hardness Tester to determine the hardness value. Data analysis was performed using One Way Anova and Post-Hoc LSD tests.There is a significant difference in the value of composite resin hardness in the entire study group. The highest hardness value was found in the group with the application of glycerin and without immersion, while the lowest value was found in the group without the application of glycerin and immersion in 120 minutes.

Effects of glycerin application on the hardness of nanofilled composite immersed in tamarind soft drinks

Background: Loss of tooth structure is a consideration in the performance of restorative treatment involving nanofilled composite resins. Material polymerization factors and water absorption can affect the hardness of composite resins. Imperfect polymerization producing an oxygen inhibited layer (OIL) and causing water absorption can even compromise the hardness of nanofilled composite resins. Tamarind soft drink, on the other hand, has an acidic pH that compromises the hardness of nanofilled composite resins. Purpose: This study aimed to reveal the effects of glycerin application on the hardness of nanofilled composite resins immersed in tamarind soft drinks. Methods: The research constituted a laboratory experiment using 24 nanofilled composite resin samples with diameters of 5mm or 2mm, divided into six groups, namely: Group G, Group G AS 60, Group G AS 120, Group TG, Group TG AS 60, and Group TG AS 120. Glycerin was applied to the surfaces of three groups before curing, while the other three groups were not treated with glycerin. Finishing was subsequently conducted on all samples using a highspeed handpiece and superfine finishing bur, before they were polished with a low speed handpiece. The samples were then divided into specific groups, namely: a group with a 120-minute immersion time, a group with a 60-minute immersion time, and a group which was not immersed and maintained at a temperature of 37oC. Each sample was tested at three points using a Vickers hardness tester (VHT). Results: The results showed that the groups with glycerin had a higher hardness level than those groups. In addition, the non-immersed groups had a higher hardness level than those groups which were immersed. The one-way ANOVA test results confirmed that there was a statistically significant difference (p&lt;0.05) between all groups. Conclusion: The application of glycerin to nanofilled composite resins immersed in tamarind soft drinks can increase their hardness levels.

Effect of Bench Time on Surface Hardness of Nanofiller Composite Resin

The purpose of this study was to evaluate the effect of different bench time on surface hardness of the composite resin after being stored in the refrigerator at 4°C. Before used in this study, the composite resin was refrigerated at 4°C for the test group and kept at 25°C for the control group. The specimens were divided into control group (I) and five experimental groups according to the bench time before polymerization, 0 (II); 15 (III); 30 (IV); 45(V); and 60 (VI) minutes. Sixty specimens with 10 mm diameter and 2 mm thickness were made by using nanofiller composite resin. The material was filled into stainless steel mold and curing for 20 s. After kept in a dark box for 24 hours, the surface hardness of all specimens were tested using Microhardness Tester. The data were analyzed with one-way ANOVA (p≤0.05) and LSD’s post hoct test. The results showed that the 60 minute bench time group presented the highest surface hardness value followed by 45, 30, 15 and 0 minutes bench time group. Moreover, the hardness value of 60 min group was almost similar with the control group. Statistical analysis showed no significant differences (p>0.05) between groups. It concluded, bench time has an effect on the surface hardness of composite resin but no significant differences statistically.

The evaluation of the surface micro-hardness values in different depth of resin blocks

Objective: Computer-aided design and manufacturing technology has shown great improvement in dentistry since the 1980s. This technology is based on a one-stage restoration using prefabricated blocks. Two main types of materials are used during CAD / CAM indirect restorations: glass-ceramic / ceramic and resin composite. CAD / CAM resin blocks are polymerized under high temperature and pressure. Polymerization depth affects the surface hardness of composite resins. When preparing a restoration, different depth layers of the resin block are used. The aim of this study is to show that adequate polymerization is achieved in each layer of the resin blocks and that the hardness of each layer is the same. Two composite resin block materials and one hybrid resin block material were included in this study. Material and method: The CAD/CAM block materials evaluated in this study were Cerasmart, Lava and Vita Enamic Square specimens (n=5/material) of approximate dimensions 10×10×2 mm blocks were sectioned (5 slices/block) from commercially available CAD-CAM materials using a diamond saw (exakt 300 cl Apparatebau, Norderstedt, Germany) with water cooling. All specimens were abraded followed by 500,1200,2500 grid using SiC abrasive paper (exakt 400 cs Apparatebau, , Norderstedt, Germany). After storage in distilled water at 37 °C for 24 hours the Knoop hardness test was performed using a hardness testing machine (Buehler MMT 3 digital micro hardness tester, Lake Bluff, IL, USA) using a load of 500 gf and a loading time of 10s. Results: The material with the highest hardness number was Vita Enamic block, whereas the lowest numbered group was the Cerasmart. The rank order of surface hardness was as follows: Vita Enamic&amp;gt; Lava Ultimate &amp;gt;Cerasmart. Conclusion: The hardness measurements of the layers of blocks were similar.

Evaluasi Nilai Kekerasan Resin Komposit Bulkfill dengan Variasi Waktu Penyinaran Sinar LED

Bulkfill composite resin can be applied in “bulk” up to 4mm and it can be cures with LED curing lights in 10 seconds. Time exposure affects the hardness of the composite resin material. This experiment aims to determine differences in exposure time with LED on the hardness of bulkfill composite resin. This experiment is a true experiment. The samples are bulkfill composite resin with diameter of 6 mm and thickness of 4 mm. There were 3 groups of samples (n=5) and cured with LED with intensity 1000mW/cm2. Group 1 was exposed for 10 seconds, group 2 for 20 seconds, and group 3 for 40 seconds. The samples were soaked in distilled water 37oC for 24 hours in waterbath. Microvickers hardness with the load of 100 grams in 15 seconds applied to the samples on the lower and the upper surface. The result found that the ratio of hardness both 10 seconds and 20 seconds, and 20 seconds and 40 seconds are no significant. The ratio hardness of 10 seconds and 40 seconds had significant difference. Based on the research irradiation time effect resin bulkfill composite hardness. It means that the more monomer polymerized the more higher hardness could be achived. The longer exposure time can make increases hardness level.

THE EFFECT OF THERMOCYCLING TEST ON THE SURFACE HARDNESS VALUE OF BULK FILL RESIN COMPOSITE

Background: Bulk fill typed composite resin can be applied at once into the tooth cavity of approximately 4 mm. The surface hardness of composite resin can be affected by temperature. Variation temperature in oral cavity due to the consumption of cold and hot food or beverages. Thermocycling tests are used to simulate aging of restorative materials in oral cavity by exposing material to repeated cycles of cold(4 oC) and hot(60°C) temperatures. Purpose: To analyze thermocycling test effect with 1500 and 3000 cycles to the surface hardness value bulk fill composite resin. Methods: This study is true experimental post test only with control group design. This study used 27 samples of bulk fill composite resin divided into 3 groups, first group is control group that did not do thermocycling test, second group is group of thermocycling 1500 cycles and third group of thermocycling 3000 cycles. Results: Mean value of composite resin surface hardness control group 46.529 ± 1.331 MPa, group thermocycling 1500 cycles 44.100 ± 1.039 MPa, and group thermocycling 3000 cycles 42.251 ± 1.470 MPa. The data were tested using One Way ANOVA and post Hoc Bonferroni with p <0.05, there were significant differences in all treatment group. Conclusion: Thermocycling test with 1500 and 3000 cycles (equal with clinically used 6 month and 1 year) in resin composites may decrease surface hardness value

THE EFFECT OF THERMOCYCLING TEST ON THE SURFACE HARDNESS VALUE OF BULK FILL RESIN COMPOSITE

Background: Bulk fill typed composite resin can be applied at once into the tooth cavity of approximately 4 mm. The surface hardness of composite resin can be affected by temperature. Variation temperature in oral cavity due to the consumption of cold and hot food or beverages. Thermocycling tests are used to simulate aging of restorative materials in oral cavity by exposing material to repeated cycles of cold(4 oC) and hot(60°C) temperatures. Purpose: To analyze thermocycling test effect with 1500 and 3000 cycles to the surface hardness value bulk fill composite resin. Methods: This study is true experimental post test only with control group design. This study used 27 samples of bulk fill composite resin divided into 3 groups, first group is control group that did not do thermocycling test, second group is group of thermocycling 1500 cycles and third group of thermocycling 3000 cycles. Results: Mean value of composite resin surface hardness control group 46.529 ± 1.331 MPa, group thermocycling 1500 cycles 44.100 ± 1.039 MPa, and group thermocycling 3000 cycles 42.251 ± 1.470 MPa. The data were tested using One Way ANOVA and post Hoc Bonferroni with p <0.05, there were significant differences in all treatment group. Conclusion: Thermocycling test with 1500 and 3000 cycles (equal with clinically used 6 month and 1 year) in resin composites may decrease surface hardness value

PENGARUH JUS JERUK DAN MINUMAN BERKARBONASI TERHADAP KEKERASAN PERMUKAAN RESIN KOMPOSIT

Background: Orange juice and Carbonat drink contains an acid agent which can affect the surface hardness of composite resin. Changes of surface hardness of composite resin is caused by infiltration of water containing the acid agent that affect the bonding of matrix to filler composite resin. This study purpose to determine the effect of immersed orange juice and carbonat drink on surface hardness of composite resin. Method: This was experimental laboratory study with a pre and post test control group design. The samples of composite resin had 12 mm in diameters and 2 mm in thickness (n=27). Composite resin used is FiltexTM Z350 XT shades A2. Samples were divided into three groups : group A immersed with orange juice, group B immersed with carbonat drink, and group C immersed with aquadest as the negative control. Samples were immersed for 24 hours. The pre and post immertion of composite resin surface hardness were measured with Micro Vickers Hardness Tester. Results: Post immertion Vickers hardness was compared by using one way anova test. The result showed that immersed orange juice and carbonat drink significantly reduced the surface hardness of composite resin (p &lt; 0,05). Concluision: The conclusion Immersed carbonat drink more reduced the surface hardness of composite than orange juice. It is suggested to reduce the duration direct exprossure of consumption carbonat drink.

Effects of three different bleaching agents on microhardness and roughness of composite sample surfaces finished with different polishing techniques.

BackgroundThe aim of this study was to evaluate effects of different polishing methods and whitening agents on surface hardness and roughness of nano-hybrid composite resin. Material and MethodsIn total, one hundred twenty disc-shaped specimens were prepared to nano-hybrid composite (Charisma Diamond). 60 samples were used for microhardness measurements and the others were used for the evaluation of surface roughness. Samples were divided randomly into two subgroups (n = 30 each). In first group a low-viscosity liquid polishing agent (Biscover LV) was applied. In the second group, nothing was applied. All the samples were stored in distilled water at 37°C for 24 h. After initial measurements were completed, samples were divided randomly into three subgroups for bleaching application. 10% carbamide peroxide (Opalescence PF), 45% carbamide peroxide (Opalescence PF Quick), 38% hydrogen peroxide (Opalescence Boost) was applied. Then microhardness and surface roughness measurements of samples were repeated and data were recorded as final values for each sample.ResultsWhen the polishing techniques were compared, no signicant difference was observed in surface hardness and roughness. When the bleaching agents were compared, the 10% carbamide peroxide and 38% hydrogen peroxide containing bleaching agent groups showed statistically significant differences between pre- and post-procedure hardness values (p<0.05).ConclusionsOffice-type bleaching agent containing CP was observed to be more secure for composite resins than other bleaching agents. No negative effect of glaze materials on the protection of surface roughness and hardness of composite resin was observed. Key words:Composite resin, bleaching, surface hardness, surface roughness.