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Abstrak :
Latar Belakang: Ekstrak Biji Anggur EBA mengandung proanthosianidin PA yang berperan sebagai pengikat silang kolagen yang menentukan sifat mekanis dentin. Tujuan: menganalisis pengaruh EBA dengan kadar PA 2 9 terhadap kekerasan mikro dentin saluran akar. Metode: 50 gigi dibagi menjadi 3 kelompok yang direndam larutan EBA larutan NaOCl 3 dan aquabides Dilakukan pengukuran nilai kekerasan mikro metode Vickers Analisis data menggunakan uji Kruskal Wallis. Hasil: Nilai kekerasan mikro tertinggi pada kelompok EBA dan terendah kelompok NaOCl 3 Tidak terdapat perbedaan bermakna nilai kekerasan mikro kelompok EBA 2 9 dan aquabides p 0 05. Kesimpulan: Larutan EBA dapat mempertahankan kekerasan mikro dentin saluran akar. ......Background: Grape Seed Extract GSE contains proanthosianidin PA as collagen cross linking agent that determine dentin mechanical properties. Aim: To analyze GSE with 2 9 PA effect on root canal dentin microhardness. Method: 50 teeth divided into 3 groups which immerse in GSE NaOCl 3 and aquabides Microhardness value measured with Vickers method Data analyze with Kruskal Wallis. Result: The highest microhardness value on GSE group and the lowest on NaOCl group No significant difference in microhardness value of GSE group compared to aquabides group p 0 05. Conclusion: GSE solution maintain microhardness value of root canal dentin.

Abstrak :
[ABSTRAK
Fe-Cr adalah paduan yang memiliki ketahanan temperatur tinggi dan potensial digunakan sebagai interkonektor pada sel bakar (SOFC=solid oxide fuel cell). Sintesis paduan Fe-Cr terus dikembangkan untuk mendapatkan metode yang efektif, dan efisien. Metode sintesis paduan Fe-Cr yang ada sekarang ini adalah metode peleburan, metalurgi serbuk ataupun metode pemaduan mekanik. Metodemetode tersebut memiliki kelemahan misalnya paduan yang tidak homogen, terdapat oksida, proses panjang dan membutuhkan waktu lama. Untuk meminimumkan permasalahan ini, adalah penting untuk menghasilkan paduan mikro Fe-Cr yang memiliki kestabilan fasa dan sifat mekanis baik. Metode ultrasonik dapat dimanfaatkan untuk sintesis paduan mikro homogen melalui penggunaan gelombang suara ultrasonik. Gelombang suara ultrasonik menghasilkan gelembung-gelembung kavitasi, setiap runtuhan kavitasi dapat dianggap sebagai reaktor mikro yang mampu menghasilkan temperatur sekitar 4737 oC dan tekanan sekitar 1000 atm dan yang terbentuk dengan sangat cepat, serta menghasilkan gelombang kejut. Dengan demikian metode ultrasonik dapat dimanfaatkan dalam pembuatan paduan mikro Fe-Cr yang homogen serta tanpa oksida dan diharapkan bisa mengatasi kelemahan metode pembuatan paduan berbasis Fe saat ini. Pada penelitian ini telah dilakukan sintesis paduan mikro Fe- Cr dengan metode ultrasonik pada frekuensi 20 kHz dalam cairan toluene. Tahapan yang telah dilakukan adalah perlakuan ultrasonik sebagai variasi waktu terhadap partikel prekursor (Fe, Cr), kemudian terhadap campuran partikel precursor untuk mendapatkan paduan mikro Fe-Cr. Kemudian dilakukan pembuatan bongkah paduan Fe-Cr dari partikel hasil perlakuan ultrasonik melalui kompaksi tanpa lubrikan dan sintering dalam kapsul kaca kuarsa. Karakterisasi yang dilakukan adalah menggunakan Scanning Electron Microscopy (SEM) terhadap partikel precursor hasil rekayasa ultrasonic. Untuk partikel campuran prekursor Fe-Cr hasil perlakuan ultrasonik karakterisasi dilakukan menggunakan SEM-EDS (Energy Dispersive Spectroscopy), X-Ray Diffraction (XRD) disertai analisis dengan metode Rietveld, Transmission Electron Microscopy-Selected Area Electron Diffraction (TEM-SAED). Untuk bongkah Fe-Cr hasil konsolidasi dengan menggunakan SEM-EDS, XRD disertai analisis dengan metode Rietveld, pengukuran densitas sebenarnya, pengujian kekerasan Vickers. Efek perlakuan ultrasonik terhadap partikel Fe adalah pengurangan ukuran, penyatuan, dan aglomerasi. Setelah perlakuan ultrasonik 40 jam terjadi peningkatan ukuran partikel Fe (>2μm). Terhadap partikel Cr memberikan efek erosi permukaan, pengurangan ukuran dan pemecahan partikel aglomerasi. Partikel Cr aglomerasi terurai sepenuhnya menjadi partikel Cr kecil (< 2 m) setelah 63 jam. Terhadap campuran partikel Fe dan Cr dapat menyatukan partikel kohesif (Fe-Fe, Cr-Cr) dan adhesif (Fe-Cr), terbentuk paduan mikro Fe-Cr seutuhnya (setelah 20 jam) ataupun paduan mikro Fe-Cr sebagian (setelah 50 jam). Pembentukan paduan mikro Fe-Cr diawali pada ukuran partikel Fe ataupun Cr < 2m. Bongkah paduan mikro Fe-Cr yang diperoleh adalah homogen dan tanpa oksida, dengan karakteristik densitas melalui sintering dua tahap yaitu tipe O = 8.655 gr/cm3, tipe B=8.179 gr/cm3, dan tipe A=8.196 gr/cm3, dan melalui proses sintering satu tahap tipe O = 7.678 gr/cm3, tipe B=7.587gr/cm3, dan tipe A=7.092 gr/cm3. Kekerasan bongkah Fe-Cr terbesar melalui sintering satu tahap yaitu 88 VHN adalah tipe B, sementara terbesar dua tahap yaitu 81 VHN adalah tipe A. Proses perlakuan ultrasonik memberikan dampak positif baik dari sisi waktu proses maupun kualitas hasil paduan Fe-Cr. Dengan demikian metode ultrasonik bisa diandalkan sebagai alternatif dalam pembuatan paduan berbasis Fe untuk mengatasi kendala homogenisasi dan oksidasi yang dihadapi pada metode saat ini.;

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ABSTRACT
Fe-Cr alloys have the potential for use as an interconnection material for solid oxide fuel cell (SOFC) due to its being resistance to high temperatures. Synthesis methods of Fe-Cr alloy continue to be developed in order to obtain a method that is both effective and efficient. Presently, the synthesis of Fe-Cr alloys include the casting, the powder metallurgy, and the mechanical alloying method. These methods have several drawbacks such as inhomogeneity in the resulting products, oxidation, and require a very time-consuming process to accomplish. In order to minimize this problem, it is important to produce Fe-Cr microalloys. Fe- Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonic methods can be used in the synthesis of homogeneous microalloys by employing the ultrasonic sound waves. Ultrasonic sound waves will generate cavitation bubbles. Any cavitation collapse can be considered as a micro reactor in which a temperature of about 4737 oC and a pressure of about 1000 atm a very rapidly created, thereby generating a shock wave. Thus, the ultrasonic method can be used in producing homogeneous and free-oxide Fe-Cr microalloys and can be expected to overcome the limitations imposed by the current methods. In this work the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of 20 kHz in toluene liquid is presented. In the synthesis procedure, the procedure steps followed were: (1) the treatment of precursor particles (Fe, Cr) through ultrasonic method with a time-variation, followed by (2) the same time-varying ultrasonic treatment on the admixture of these specially prepared precursor particles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantless compaction method was employed on these precursor particles admixture followed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy. Observations of the specially prepared precursor particles using ultrasonic technique were carried out by scanning electron microscopy (SEM) method. Observation of the precursor mixture of Fe-Cr particles mixture treated ultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy) apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysis method, and transmission electron microscopy (TEM)-selected area electron diffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS, XRD accompanied by analysis by the Rietveld method, true density measurement, and Vickers microhardness testing. Ultrasonic treatment has caused Fe particles to form agglomerations, an interparticles neck formation, and a fusing among the particles. The size of the Fe particles increased (>2μm) after 40 hours treatment. The agglomerated Cr particles experienced fragmentation, surface erosion, and reduction of particle size. The agglometrated Cr particles fully disintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixture of Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, forming completely (after ultrasonic treatment for 20 hours) and partially (after ultrasonic treatment for 50 hours) Fe-Cr microalloys. The complete formation of Fe-Cr microalloy was possible with an equal particle size of the precursor Fe and Cr (approximately <2 μm). The bulk of Fe-Cr alloy results are homogenous and oxide-free. For two-step sintering, its density (in gr/cm3 unit) is 8.655 for type O, is 8.179 for type B, and is 8.196 for type A, and for one-step sintering its density is 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatest microhardness number of 88 VHN is of type B (one-step sintering), and of 81 VHN is of type A (two-step sintering). The ultrasonic treatment process has a positive impact, with respect to both of quality and time-consumption to finish the Fe-Cr alloying process. Therefore the ultrasonic method can be relied upon as an alternative method in the production of Fe-based alloys to solve problems in homogenization and oxidation encountered in current methods;Fe-Cr alloys have the potential for use as an interconnection material for solid oxide fuel cell (SOFC) due to its being resistance to high temperatures. Synthesis methods of Fe-Cr alloy continue to be developed in order to obtain a method that is both effective and efficient. Presently, the synthesis of Fe-Cr alloys include the casting, the powder metallurgy, and the mechanical alloying method. These methods have several drawbacks such as inhomogeneity in the resulting products, oxidation, and require a very time-consuming process to accomplish. In order to minimize this problem, it is important to produce Fe-Cr microalloys. Fe- Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonic methods can be used in the synthesis of homogeneous microalloys by employing the ultrasonic sound waves. Ultrasonic sound waves will generate cavitation bubbles. Any cavitation collapse can be considered as a micro reactor in which a temperature of about 4737 oC and a pressure of about 1000 atm a very rapidly created, thereby generating a shock wave. Thus, the ultrasonic method can be used in producing homogeneous and free-oxide Fe-Cr microalloys and can be expected to overcome the limitations imposed by the current methods. In this work the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of 20 kHz in toluene liquid is presented. In the synthesis procedure, the procedure steps followed were: (1) the treatment of precursor particles (Fe, Cr) through ultrasonic method with a time-variation, followed by (2) the same time-varying ultrasonic treatment on the admixture of these specially prepared precursor particles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantless compaction method was employed on these precursor particles admixture followed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy. Observations of the specially prepared precursor particles using ultrasonic technique were carried out by scanning electron microscopy (SEM) method. Observation of the precursor mixture of Fe-Cr particles mixture treated ultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy) apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysis method, and transmission electron microscopy (TEM)-selected area electron diffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS, XRD accompanied by analysis by the Rietveld method, true density measurement, and Vickers microhardness testing. Ultrasonic treatment has caused Fe particles to form agglomerations, an interparticles neck formation, and a fusing among the particles. The size of the Fe particles increased (>2μm) after 40 hours treatment. The agglomerated Cr particles experienced fragmentation, surface erosion, and reduction of particle size. The agglometrated Cr particles fully disintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixture of Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, forming completely (after ultrasonic treatment for 20 hours) and partially (after ultrasonic treatment for 50 hours) Fe-Cr microalloys. The complete formation of Fe-Cr microalloy was possible with an equal particle size of the precursor Fe and Cr (approximately <2 μm). The bulk of Fe-Cr alloy results are homogenous and oxide-free. For two-step sintering, its density (in gr/cm3 unit) is 8.655 for type O, is 8.179 for type B, and is 8.196 for type A, and for one-step sintering its density is 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatest microhardness number of 88 VHN is of type B (one-step sintering), and of 81 VHN is of type A (two-step sintering). The ultrasonic treatment process has a positive impact, with respect to both of quality and time-consumption to finish the Fe-Cr alloying process. Therefore the ultrasonic method can be relied upon as an alternative method in the production of Fe-based alloys to solve problems in homogenization and oxidation encountered in current methods, Fe-Cr alloys have the potential for use as an interconnection material for solid oxide fuel cell (SOFC) due to its being resistance to high temperatures. Synthesis methods of Fe-Cr alloy continue to be developed in order to obtain a method that is both effective and efficient. Presently, the synthesis of Fe-Cr alloys include the casting, the powder metallurgy, and the mechanical alloying method. These methods have several drawbacks such as inhomogeneity in the resulting products, oxidation, and require a very time-consuming process to accomplish. In order to minimize this problem, it is important to produce Fe-Cr microalloys. Fe- Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonic methods can be used in the synthesis of homogeneous microalloys by employing the ultrasonic sound waves. Ultrasonic sound waves will generate cavitation bubbles. Any cavitation collapse can be considered as a micro reactor in which a temperature of about 4737 oC and a pressure of about 1000 atm a very rapidly created, thereby generating a shock wave. Thus, the ultrasonic method can be used in producing homogeneous and free-oxide Fe-Cr microalloys and can be expected to overcome the limitations imposed by the current methods. In this work the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of 20 kHz in toluene liquid is presented. In the synthesis procedure, the procedure steps followed were: (1) the treatment of precursor particles (Fe, Cr) through ultrasonic method with a time-variation, followed by (2) the same time-varying ultrasonic treatment on the admixture of these specially prepared precursor particles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantless compaction method was employed on these precursor particles admixture followed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy. Observations of the specially prepared precursor particles using ultrasonic technique were carried out by scanning electron microscopy (SEM) method. Observation of the precursor mixture of Fe-Cr particles mixture treated ultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy) apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysis method, and transmission electron microscopy (TEM)-selected area electron diffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS, XRD accompanied by analysis by the Rietveld method, true density measurement, and Vickers microhardness testing. Ultrasonic treatment has caused Fe particles to form agglomerations, an interparticles neck formation, and a fusing among the particles. The size of the Fe particles increased (>2μm) after 40 hours treatment. The agglomerated Cr particles experienced fragmentation, surface erosion, and reduction of particle size. The agglometrated Cr particles fully disintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixture of Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, forming completely (after ultrasonic treatment for 20 hours) and partially (after ultrasonic treatment for 50 hours) Fe-Cr microalloys. The complete formation of Fe-Cr microalloy was possible with an equal particle size of the precursor Fe and Cr (approximately <2 μm). The bulk of Fe-Cr alloy results are homogenous and oxide-free. For two-step sintering, its density (in gr/cm3 unit) is 8.655 for type O, is 8.179 for type B, and is 8.196 for type A, and for one-step sintering its density is 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatest microhardness number of 88 VHN is of type B (one-step sintering), and of 81 VHN is of type A (two-step sintering). The ultrasonic treatment process has a positive impact, with respect to both of quality and time-consumption to finish the Fe-Cr alloying process. Therefore the ultrasonic method can be relied upon as an alternative method in the production of Fe-based alloys to solve problems in homogenization and oxidation encountered in current methods]

Abstrak :
Tujuan: Menganalisis perbedaan microhardness dan flexural strength dentin saluran akar setelah paparan berbagai larutan irigasi endodontik regeneratif. Metode: Tiga puluh enam sampel dentin gigi manusia yang baru diekstraksi dibagi menjadi 6 kelompok yaitu 2 kelompok kontrol (NaCl 0,9%), 2 kelompok uji 1 diirigasi dengan 20 ml NaOCl 1,5% selama 5 menit – 3 ml NaCl 0,9% selama 3 menit – 20 ml EDTA 17% selama 5 menit, 2 kelompok uji 2 diirigasi dengan 20 ml NaOCl 1,5% selama 5 menit – 3 ml PBS 10% selama 3 menit – 20 ml EDTA 17% selama 5 menit – 3 ml PBS 10% selama 3 menit. Perubahan microhardness dan flexural strength dievaluasi dengan uji Vickers dan 3-Point Flexural Tester. Data dianalisis menggunakan One-Way ANOVA dan Tamhane. Hasil: Terdapat perbedaan bermakna antar kelompok uji 1 dan 2 dengan kelompok kontrol (One-Way ANOVA, p < 0,05). Berdasarkan uji Post Hoc (Tamhane, p<0,05) terdapat perbedaan bermakna microhardness dan flexural strength kelompok uji 2 dibandingkan kelompok uji 1, dengan nilai rerata lebih tinggi pada kelompok uji 2 terhadap kelompok uji lainnya. Kesimpulan: Kelompok uji 2 memiliki nilai microhardness dan flexural strength lebih baik sebagai bahan regenerasi endodontik regeneratif. ......Objective: To analyze the differences in microhardness and flexural strength of root canal dentin after exposure various regenerative endodontic irrigation solution. Methods: Thirty-six dentine samples from fresh extracted were assigned to 6 groups, two groups as a control (NaCl 0,9%), two test groups 1 (20 ml NaOCl 1,5% for 5 min – 3 ml NaCl 0,9% for 3 min – 20 ml EDTA 17% for 5 min), two test groups 2 (20 ml NaOCl 1,5% for 5 min – 3 ml PBS 10% for 3 min – 20 ml EDTA 17% for 5 min – 3 ml PBS 10% for 3 min). The changing of microhardness and flexural strength were evaluated using Vickers and 3-point flexural tester. Data were analysed using One-Way ANOVA and Tamhane. Result: There was significant difference between test groups 1 and 2 with control group (One-Way ANOVA, p < 0,05). Based on the Post hoc test (Tamhane, p < 0,05 ), showed significant difference in microhardness and flexural strength between group 2 and group 1, with higher mean in test group 2 compared to other test groups. Conclusion: Test group 2 had better microhardness and flexural strength as regenerative endodontic irrigation.

Abstrak :
Penelitian dilakukan untuk mengetahui pengaruh perendaman dalam larutan kayu manis terhadap kekerasan mikro email gigi manusia dengan menggunakan Shimadzu Micro Hardness Tester HMV-2. Delapan spesimen gigi premolar atas manusia dibagi menjadi kelompok perendaman larutan 4% dan 12,5%, selama 60 menit, 120 menit, dan 180 menit. Pengukuran kekerasan menggunakan indenter Knoop, sebelum dan setelah perlakuan. Data dianalisis dengan Repeated ANOVA dan Independent T-Test. Perendaman dalam larutan 4% selama 60 menit dan 120 menit menurunkan kekerasan. Sebaliknya, perendaman selama 180 menit meningkatkan kekerasan. Perendaman dalam larutan 12,5% hingga180 menit menurunkan kekerasan. Perendaman gigi dalam larutan kayu manis dapat menyebabkan perubahan kekerasan. ...... This research was conducted to understand the effect of immersion of the human tooth enamel in cinnamon extract solution to the enamel microhardness using Shimadzu Micro Hardness Tester HMV-2. Eight specimens of maxillary premolar soaked in 4% and 12,5% solution for 60 minutes, 120 minutes, and 180 minutes. Hardness measurements using Knoop indenter performed before and after treatment. Data were analyzed by Repeated ANOVA and Independent T-Test. Immersion in 4% solution for 60 minutes and 120 minutes reduce microhardness. Soaking for 180 minutes will increase microhardness. Soaking in 12,5% solution for 180 minutes reduce microhardness. Enamel immersion may change microhardness.

Abstrak :
Latar belakang : Resin komposit bulkfill merupakan resin terbaru yang dapat direstorasi dengan kedalaman 4-5 mm dalam sekali penyinaran. Polimerisasi dipengaruhi oleh durasi penyinaran dan besaran irradiansi lightcuring untuk mendapatkan kekerasan permukaan dan depth of cure yang optimal. Tujuan: Penelitian ini bertujuan untuk mengetahui perbedaan nilai kekerasan resin komposit dan depth of cure resin komposit Tetric® N- Ceram bulk-fill yang disinari lightcure dengan durasi 5 detik, 10 detik dan 15 detik. Metode Penelitian: Dalam penelitian ini digunakan 24 spesimen resin komposit Tetric® N-Ceram bulk-fill berbentuk silinder dengan ukuran diameter 6 mm dan tebal 4 mm. Selembar mylar strip diletakkan diatas permukaan resin komposit sebelum dilakukan proses curing. Polimerisasi dilakukan menggunakan Light Curing Unit (LED DBA iLed) selama 5 detik, 10 detik dan 15 detik dengan irradiansi 1100 mW/cm2. Setelah polimerisasi, spesimen direndam dalam akuades pada suhu 37oC selama 24 jam. Spesimen dibagi menjadi tiga kelompok (n=8) yaitu; kelompok resin komposit dengan penyinaran 5 detik, penyinaran 10 detik dan penyinaran 15 detik. Spesimen diuji menggunakan HMV-G Series Micro Vickers Hardness Tester (Shimadzu, Jepang) dengan beban 100 gram selama 10 detik untuk mendapatkan nilai kekerasan. Data dianalisis dengan uji statistik Kruskall Wallis dan Post-Hoc Mann Whitney. Hasil Penelitian: Hasil uji statistik menunjukkan kenaikan bermakna nilai kekerasan permukaan dan depth of cure pada resin komposit Tetric® N-Ceram bulk-fill. Nilai kekerasan dan depth of cure tertinggi terlihat pada resin komposit Tetric® N-Ceram bulk-fill pada kelompok penyinaran 15 detik, yaitu sebesar 41,61 ± 1,25 KHN dan 72,71 ± 1,88. Kesimpulan: Disimpulkan bahwa semakin bertambah durasi penyinaran lightcure yang disinari, semakin bertambah nilai kekerasan permukaan dan depth of cure resin komposit Tetric® N-Ceram bulk-fill. ......Background : Bulkfill composite resin is the newest resin that can be restored to a depth of 4-5 mm in one step. Polymerization is determined by the irradiation time and the amount of light curing irradiance to obtain optimal microhardness and depth of cure. Objective: The aim of this study was to determine the difference in the value of the microhardness of the composite resin and the depth of cure of the Tetric® N-Ceram bulk- fill composite resin irradiated by lightcure with a duration of 5 seconds, 10 seconds and 15 seconds. Method: Twenty four specimens of Tetric® N-Ceram bulk-fill Composite Resin were used in this study. All materials were prepared into disk-shaped specimens of 6 mm in diameter and 4 mm in thickness. A piece of mylar strip was placed on the top of the specimens just before the polymerization.. Polymerization was carried out using a Light Curing Unit (LED DBA iLed) for 5 seconds, 10 seconds and 15 seconds with an irradiance of 1100 mW/cm2. After polymerization, specimens were immersed in 37 aquadest solution for 24 hours. Specimens were divided into three groups (n=8) that is; composite resin group with 5 seconds of irradiation, 10 seconds of irradiation and 15 seconds of irradiation. Specimens were tested with HMV-G Series Micro Vickers Hardness Tester (Shimadzu, Jepang) with 100 gram indentation in 10 seconds. Data were analyzed using Kruskall Wallis and Post-Hoc Mann Whitney to assess the significant differences among groups Result: The results of statistical tests showed a significant increase in the value of microharhardness and depth of cure on Tetric® N-Ceram bulk- fill composite resin. The highest microhardness and depth of cure values were seen in the Tetric® N-Ceram bulk-fill composite resin in the 15 second irradiation group, namely 41.61 ± 1.25 KHN and 72.71 ± 1.88. Conclusion: It was concluded that the longer the duration of irradiation of the irradiated lightcure, the higher the microhardness value and depth of cure of the Tetric® N-Ceram bulk-fill composite resin.

Abstrak :
Latar Belakang: Aplikasi Mineral Trioxide Aggregate (MTA) sebagai material bioaktif yang umum digunakan dalam upaya remineralisasi affected dentin memiliki peranan penting dalam preservasi jaringan gigi pada perawatan terapi pulpa vital, namun diketahui tidak dapat menghasilkan dentin dengan sifat mekanis menyerupai dentin sehat karena hanya menghasilkan remineralisasi ekstrafilbrillar. Carboxymethyl Chitosan (CMC) merupakan biomaterial alami yang dikembangkan sebagai analog protein non-kolagen pada dentin untuk menghambat laju presipitasi kalsium fosfat yang dihasilkan oleh interaksi antara material bioaktif dengan jaringan sehingga dapat memasuki ruang intrafibrillar kolagen. Tujuan: Mengetahui pengaruh penambahan CMC pada semen MTA terhadap perubahan karakteristik kristal hidroksiapatit dan kekerasan mikro dentin terdemineralisasi, yang diobservasi selama 14 hari periode remineralisasi. Metode: Remineralisasi dilakukan melalui aplikasi material MTA, MTA-CMC 5%, dan MTA-CMC 10% pada dasar kavitas sampel dentin terdemineralisasi. Akar gigi direndam selama 14 hari dalam cairan phosphate-buffered saline. Observasi karakteristik kristal hidroksiapatit dilakukan dengan alat uji X-ray Diffractomete dan perubahan kekerasan mikro dianalisis secara kuantitatif melalui uji Vickers Hardness. Hasil: Pembentukan kristal hidroksiapatit ditemukan pada sampel MTA dan MTA-CMC dengan derajat kristalinitas hidroksiapatit paling tinggi pada sampel MTA-CMC 10%. Kekerasan mikro dentin meningkat pada kelompok MTA-CMC 5% dan MTA-CMC 10% dibandingkan pada kelompok MTA. Kesimpulan: Aplikasi modifikasi material Mineral Trioxide Aggregate dengan Carboxymethyl Chitosan selama 14 hari menginisasi terbentuknya fase mineral hidroksiapatit dan meningkatkan derajat kristalinitas hidroksiapatit pada dentin terdemineralisasi serta meningkatkan kekerasan mikro dentin terdemineralisasi. ......Background: Application of Mineral Trioxide Aggregate (MTA) as remineralization agent of affected dentin which holds a vital role in the preservation of tooth structure has been widely used in clinical practice, however it’s only capable of generating extrafibrillar remineralization resulting in the inability to produce dentin with mechanical properties resembling sound dentin. Carboxymethyl Chitosan (CMC) is a natural biomaterial developed as analogue of dentin non-collagenous proteins to inhibit the spontaneous precipitation of calcium-phosphate produced by the interaction of dentin with remineralization agent so that intrafibrillar remineralization can be accomplished. Objective: To evaluate hydroxyapatite crystals characteristic and assess the microhardness of demineralized dentin after 14 days application of CMC-modified MTA. Method: Remineralization was performed by the application of MTA, MTA-CMC 5%, and MTA-CMC 10% on demineralized dentin samples. During the remineralization process, root canals of tooth models were immersed in phosphate-buffered saline solution. Hydroxyapatite crystals’ characteristic was observed by X-ray Diffractometer, while dentin microhardness score was assessed by Vickers Hardness test. Result: Formation of hydroxyapatite crystals was identified in MTA and MTA-CMC samples. Highest degree of crystallinity was found in MTA-CMC10% sample. Microhardness score of demineralized dentins in MTA-CMC 5% group and MTA-CMC 10% group was significantly higher than those in MTA group. Conclusion: CMC-modified MTA application on demineralized dentin in 14 days was found effective in initiating hydroxyapatite formation with higher degree of crystallinity and increasing the microhardness of demineralized dentin.

Abstrak :
ABSTRAK Dalam penggunaannya di rongga mulut, resin komposit dapat mengalami degradasi oleh asam, terutama pada pasien dengan resiko karies tinggi. Resin komposit alkasit merupakan material dual-cured yang berbasis UDMA dan mampu melepaskan ion fluor, kalsium, dan hidroksida. Adanya ion hidroksida yang dilepaskan diketahui dapat menetralkan suasana asam. Namun, belum diketahui bagaimana pengaruh pH saliva buatan terutama pH kristis hidroksiapatit dan fluoroapatit terhadap sifat kekerasan resin komposit alkasit. Penelitian ini dilakukan untuk melihat pengaruh pH saliva buatan terhadap kekerasan resin komposit alkasit polimerisasi kimia dan cahaya. Penelitian berupa eksperimental laboratorik dengan menggunakan masing-masing 48 spesimen resin komposit alkasit (Cention-N, Ivoclar-Vivadent, Liechstenstein) polimerisasi kimia dan cahaya. Spesimen berbentuk silindris dengan diameter 6 mm dan tinggi 2 mm yang dibagi menjadi 16 kelompok perendaman. Perendaman dilakukan pada pH saliva buatan 4,5 dan 5,5 dengan lama perendaman 1, 3, 5, dan 7 hari di dalam inkubator dengan suhu 37°C. Uji kekerasan menggunakan Knoop Microhardness Tester (HMV-G Shimadzu). Hasil penelitian menunjukkan adanya penurunan kekerasan pada resin komposit alkasit polimerisasi kimia dan cahaya setelah dilakukan perendaman selama 1, 3, 5, dan 7 hari dalam saliva buatan dengan pH 4,5 dan 5,5. Nilai kekerasan tertinggi terlihat pada resin komposit alkasit polimerisasi cahaya setelah perendaman 1 hari pada pH saliva buatan 5,5 yaitu 58,41±0,23 KHN. Sedangkan nilai kekerasan terendah terlihat pada resin komposit alkasit polimerisasi kimia setelah perendaman 7 hari pada pH saliva buatan 4,5 yaitu 47,38±0,49 KHN. Berdasarkan uji statistik One-way Anova terdapat perbedaan bermakna (p<0,05) antar kelompok lama perendaman pada pH saliva buatan 4,5 dan 5,5. Hasil uji statistik Independent T-test menunjukkan terdapat perbedaan bermakna (p<0,05) antar kelompok pH saliva buatan dan antar kelompok metode polimerisasi. Dapat disimpulkan bahwa terdapat penurunan nilai kekerasan resin komposit alkasit seiring dengan semakin rendahnya pH saliva buatan dan semakin lamanya perendaman dengan penurunan terbesar pada perendaman 1 hari pertama.

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ABSTRACT In its application in the oral cavity, composite resins can be degraded by acids, especially in patients with a high caries risk. Alkasite composite resin is a dual-cured material based on UDMA and capable of releasing fluoride, calcium, and hydroxide ions. The presence of hydroxide ion which released to its environtment can neutralize the acidic condition. However, it has not yet determined how saliva pH, especially the critical saliva pH for hydroxyapatite and fluoroapatite, affects the hardness properties of alkasite composite resins. The aim of this study was to determine the effect of artificial saliva pH on the hardness of self-cured and dual-cured alkasite composite resin. This laboratory study used 48 cylindrical-shaped specimens with 6 mm in diameter and 2 mm in thickness of alkasite composite resin specimens (Cention-N, Ivoclar-Vivadent, Liechstenstein) for each polymerization methods. The specimens were divided into 16 groups for immersion in artificial saliva pH 4.5 and 5.5 and then stored in an incubator at 37°C for the next 1, 3, 5, 7 days. The hardness test was performed using a Knoop Microhardness Tester (HMV-G Shimadzu). The results showed that the hardness of self-cured and dual-cured alkasite composite resins decreased after immersion. The highest hardness value was seen in dual-cured alkasite composite resin after 1 day immersion in artificial saliva pH of 5.5 (58.41 ± 0.23 KHN). While the lowest hardness value was seen in the self-cured alkasite composite resin after 7 days immersion in artificial saliva pH 4.5 (47.38 ± 0.49 KHN). Based on the One-way Anova statistical test, there were significant differences (p <0.05) between the different immersion time groups in each artificial saliva pH. The results of the Independent T-test statistical test showed that there were significant differences (p <0.05) between the artificial saliva pH groups and between polymerization methods groups. It was concluded that there was a decrease in the hardness of alkasite composite resin along with the lower pH of artificial saliva and the increasing immersion time. The greatest decrease occured in the first day of immersion.

Abstrak :
Tujuan: Penelitian ini bertujuan untuk mengetahui perbedaan nilai kekerasan resin komposit microhybrid G-aenial Posterior™ setelah perendaman dalam saliva buatan dengan pH 4,5; 5,5; dan 7 selama 1 hari dan 7 hari.Metode Penelitian: Dalam penelitian ini digunakan 36 spesimen resin komposit microhybrid G-aenial Posterior™ berbentuk silinder dengan ukuran diameter 6 mm dan tebal 2 mm. Selembar mylar strip diletakkan diatas permukaan resin komposit sebelum dilakukan proses curing. Polimerisasi dilakukan menggunakan Light Curing Unit (LED DBA iLed) selama 10 detik dengan irradiansi 1200 mW/cm2. Setelah polimerisasi, spesimen direndam dalam akuades pada suhu 37oC selama 24 jam. Spesimen dibagi menjadi enam kelompok (n = 6) yaitu; perendaman pada saliva buatan pH 4,5 selama 1 hari, saliva buatan pH 5,5 selama 1 hari, saliva buatan pH 7 selama 1 hari, saliva buatan pH 4,5 selama 7 hari, saliva buatan pH 5,5 selama 7 hari, dan saliva buatan pH 7 selama 7 hari. Spesimen diuji menggunakan HMV-G Series Micro Vickers Hardness Tester (Shimadzu, Jepang) dengan beban 50 gram selama 15 detik untuk mendapatkan nilai kekerasan. Data dianalisis dengan uji statistik One-Way ANOVA dan Post-Hoc Bonferroni. Hasil Penelitian: Hasil uji statistik menunjukkan penurunan bermakna nilai kekerasan material G-aenial PosteriorTM setelah dilakukan perendaman selama 1 dan 7 hari dalam saliva buatan dengan pH 4,5; 5,5; dan 7. Nilai kekerasan tertinggi terlihat pada resin komposit microhybrid G-aenial Posterior™ setelah perendaman 1 hari pada pH saliva buatan pH 7 yaitu sebesar 19,14 ± 0,61 VHN. Sedangkan nilai kekerasan terendah terlihat pada resin komposit microhybrid G-aenial Posterior™ setelah perendaman 7 hari pada pH saliva buatan pH 4,5 yaitu sebesar 14,37 ± 0,31 VHN. Kesimpulan: Disimpulkan bahwa dengan pertambahan waktu perendaman, dan penurunan pH saliva buatan didapatkan nilai kekerasan yang menurun pada resin komposit microhybrid G-aenial PosteriorTM. ......Objective: The aim of this study was to determine the difference of Microhybrid G-Aenial Posterior™ Composite Resin hardness value after immersion in artificial saliva with pH 4.5; 5.5; and 7 for 1 day and 7 days. Method: 36 specimens of Microhybrid G-Aenial Posterior™ Composite Resin were used in this study. All materials were prepared into disk-shaped specimens of 6 mm in diameter and 2 mm in thickness. A piece of mylar strip was placed on the top of the specimens just before the polymerization. Polymerization was done using LED curing unit (LED DBA iLed) in 10 seconds with irradiance 1200 mW/cm2. After polymerization, specimens were immersed in 37C aquadest solution for 24 hours. Specimens were divided into six groups (n=6) immersed with artificial saliva pH 4,5 in a day; pH 5,5 in a day; pH 7 in a day; pH 4,5 in 7 days; pH 5,5 in 7 days; and pH 7 in 7 days. Specimens were tested with HMV-G Series Micro Vickers Hardness Tester (Shimadzu, Japan) with 50 gram indentation in 15 seconds. Data were analyzed using One-Way ANOVA and Post-Hoc Bonferroni to assess the significant differences among groups. Result: The result showed hardness significant decreased of G-aenial PosteriorTM after were immersed in 1 and 7 days in 4,5; 5,5; dan 7 pH of artificial saliva. The highest and lowest hardness value seen in microhybrid G-aenial Posterior™ composite resin after were immersed in one day with pH 7 of artificial saliva (19,14 ± 0,61 VHN) and 7 days with pH 4,5 (14,37 ± 0,31 VHN) respectively. Conclusion: It was concluded that the increased immersion time and the decrease in the pH value of the artificial saliva decreased the hardness value of the G-aenial PosteriorTM microhybrid composite resin.

Abstrak :
Latar Belakang: Resin komposit Giomer Bulk-Fill merupakan resin komposit yang dapat ditumpat hingga ketebalan 4 mm dan dapat melepas ion fluor. Resin komposit ini juga menjadi buffer asam ketika tingkat pH saliva turun dan mengembalikan ke pH netral. Namun, kenaikan pH diikuti dengan penurunan sifat fisik dari material. Belum diketahui apakah terdapat pengaruh terhadap kekerasan permukaan setelah material ini melepas fluor dan perubahan pH saliva. Tujuan: Untuk mengetahui pengaruh perbedaan pH saliva buatan dan lama perendaman terhadap kekerasan permukaan resin komposit Giomer Bulk-Fill. Metode: Penelitian eksperimental laboratorik menggunakan sembilan puluh spesimen resin komposit Giomer Bulk-Fill berdiameter 6 mm dan tinggi 3 mm dibagi menjadi 9 kelompok perendaman yaitu dengan saliva buatan pH 7 (kontrol); pH 5,5; pH 4,5 dengan lama perendaman 1 jam, 24 jam, dan 72 jam yang disimpan dalam inkubator dengan suhu 37°C. Uji kekerasan menggunakan Knoop Microhardness Tester (Shimadzu HMV-G21DT, Jepang). Hasil: Berdasarkan hasil uji statistik One-way ANOVA terdapat perbedaan bermakna (p<0,05) antara kelompok perendaman dalam saliva buatan pH 4,5 dengan kelompok perendaman dalam saliva buatan pH 5,5 dan kelompok perendaman dalam saliva buatan pH 4,5 dengan kelompok perendaman dalam saliva buatan pH 7 yang dilakukan perendaman selama 72 jam. Nilai kekerasan pada perendaman dengan saliva buatan pH 4,5 dan lama perendaman 1 jam, 24 jam, dan 72 jam beruturut-turut sebesar 35,9±2,40 KHN, 33,75±2,98 KHN, dan 32,7±2,71 KHN. Sementara itu, nilai kekerasan dengan saliva buatan pH 5,5 dan lama perendaman 1 jam, 24 jam, dan 72 jam beruturt-turut sebesar 38,92±2,96 KHN, 37,00±1,82 KHN, dan 38,6±3,42 KHN. Dengan larutan saliva buatan pH 7 dan lama perendaman 1 jam, 24 jam, dan 72 jam didapatkan nilai kekerasan berturut-turut adalah 37,01±2,21 KHN, 37,05±1,79 KHN dan 37,72±2,51 KHN. Kesimpulan: Lama perendaman dan tingkat keasaman dalam saliva buatan dapat menurunkan nilai kekerasan permukaan resin komposit Giomer Bulk-Fill.

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Introduction: Composite resin Giomer Bulk-Fill is a material for restoration that can be placed in single increment with depth until 4 mm and release fluoride ion. This composite resin can be an acidic buffer when pH saliva drops and turns it back to pH neutral. However, the physical properties of the material are decreased. It is unknown if there any change of surface hardness of the material due to fluoride ion release and changes in pH saliva. Objective: This study aimed to determine the effect of immersion time and different pH levels of artificial saliva on surface microhardness of composite resin Giomer Bulk-Fill. Methods: Laboratory experimental research using ninety specimens of resin composite Giomer Bulk-Fill and divided into nine groups with immersion in artificial saliva pH 7 (control); 5,5; and 4,5 for 1, 24, and 72 hours at 37°C respectively and tested using Knoop Microhardness Tester (Shimadzu HMV-G21DT, Japan). Result: The statistical test using One-way ANOVA showed that there were significant differences (p<0,05) between group of immersion in artificial saliva pH 4,5 compared to group of immersion in artificial saliva pH 5,5 and group of immersion in artificial saliva pH 5,5 compared to group of immersion in artificial saliva pH 7 for 72 hours of immersion. The result showed that the hardness number of the groups immersed in artificial saliva pH 4,5 for 1 hour, 24 hours, and 72 hours respectively are 35,9±2,40 KHN, 33,75±2,98 KHN, and 32,7±2,71 KHN. Meanwhile, the hardness number of the groups immersed in artificial saliva pH 5,5 for 1 hour, 24 hours, and 72 hours respectively 38,92±2,96 KHN, 37,00±1,82 KHN, and 38,6±3,42 KHN. The hardness number of the groups immersed in aritificial saliva of pH 7 for 1 hours, 24 hours, and 72 hours are 37,01±2,21 KHN, 37,05±1,79 KHN dan 37,72±2,51 KHN. Conclusion: Different immersion times and pH levels decrease surface microhardness of Giomer Bulk-Fill composite resin.