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"Duplex siainless steel relalz bmiyak digunakan dalam berbagai bidang apliknsi_ Aplilcasi marcrial ini yang begin: besm' dikarenakan kelahanan malarial ierxebui rerhadap ko/'osi_ Kekuaran dan kemngguhan _mug iinggi. dan juga mempunyai kelmaian_kzrilr _mug linggi. Karakferislik maierial ini sangai dipengaruhi ke.s'f:limhai1gan_krsa _/nfffil-(1)1511-Iliff. diumna keseiimbangan dl1H_ff?SG ini drpengaru/ai ole/1 komposisi kimia dan sikiux icrmnl yang dialami sebelumnya. Karena prosrfs pengelasmz maka msio komposisi kedua,kzsa nlmn berubah dan dapar mengakibailcan perubuharr SMI! mekanis material ini.I’ene/irian ini herriguan :mink ineli/mi pengaruh perlnlcuan panax :mil dan merode pendinginan (waler quenching dan air cooling) lerhadnp mikrosirukrur dan kekerasan mikro pada lasan duplex slainless steel UNS S31803. Perlalfuan pcmas ini juga akan mcmberikcm dam perubahan imndungan _/2150 _ferir yang akan mcmpengaruhi kekerasrm milcro.Perlairuan pcmas :mil pnda iemperaiur ll00°C memlnerilcan keserimbangan _krii dan ausfenii _Dada semua daernh _vang mendistribusikan kekerasan secara meraia_ Lap: pendinginan memberikan pengaruh yung berbeda rcrhadap kesetimbangan _£2sa. Pendinginan cepar 0nedia air) alarm menghasilkan kandungan _/érir yang lebih banyak. sedangkan pendinginan lamba! (media udara) menghasilkan kandungcm jérit lcurang dari pendingirmn cepat."

"Boronisasi pada baja karbon ST37 dan S45C telah dilakukan menggunakan teknik powder pack. Komposisi serbuk yang digunakan terdiri atas 5% B4C, 5% KBF4 dan 90% SiC. Boronisasi dilakukan pada temperatur 1000 oC selama 8 jam dalam kondisi atmosfir inert menggunakan gas argon. Boronisasi yang dilakukan pada kedua baja menghasilkan lapisan borida diluar permukaan baja dan pada permukaannya. Ketebalan lapisan borida diluar permukaan pada baja ST37 setebal 43 μm yang lebih tebal dibandingkan pada baja S45C yang hanya setebal 31 μm. Kedalaman lapisan borida yang terbentuk pada baja ST37 sedalam 250 μm yang lebih dalam dan runcing dibandingkan lapisan borida yang terbentuk pada baja S45C yang hanya sedalam 243 μm. Analisis fasa pada permukaan lapisan borida untuk beberapa kedalaman dilakukan menggunakan XRD dan aplikasi GSAS. Dari pola difraksi teridentifikasi fasa FeB, Fe2B dan CrB pada kedua jenis baja yang digunakan. Hasil analisis GSAS menunjukkan fasa FeB merupakan fasa dengan fraksi berat yang dominan sampai kedalaman 55 μm dari permukaan baja untuk baja ST37 dan sampai kedalaman 41 μm dari permukaan baja untuk baja S45C. Semakin kedalam, fraksi berat fasa FeB semakin berkurang seiring dengan peningkatan fraksi berat Fe2B dan CrB. Kekerasan mikro lapisan borida dari penampang lintang diperoleh berkisar antara 1300-1800HV. Sedangkan kekesaran mikro lapisan borida dari permukaan lapisan borida diperoleh berkisar 750-4500HV. Kekerasan mikro dari permukaan yang tertinggi pada kedua baja terukur pada saat fraksi berat fasa FeB yang tertinggi. Semakin ke dalam, kekerasan mikro lapisan borida relatif berkurang tetapi tetap lebih tinggi dari kekerasan mikro matriks dan fasa CrB masih teridentifikasi. Dapat disimpulkan, kekerasan mikro lapisan borida dari permukaan terluar sampai dikedalaman 50 μm dipengaruhi oleh fasa FeB. Kekerasan mikro lapisan borida dikedalaman lebih dari 50 μm lebih dipengaruhi oleh fasa CrB.

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Boronizing on ST37 and S45C carbon steel has been done through powder pack technique using powder of 5% B4C, 5% KBF4 and 90% SiC. The process carried out at isothermal temperature at 1000 °C for 8 hours in an inert atmosphere. The boride layers formed in outside and on the surface both of steels. The thickness of boride layer outside the surface on ST37 steel was 43 μm and 31 μm on the S45C steel. The depth of boride layers that formed on the surface ST37 steel was 250 μm. It was deeper than the depth of boride layers that formed on S45C steel which only 243 μm. The boride layers phases analysis for some depths carried out using XRD and GSAS application. The diffraction pattern identified that the FeB, Fe2B and CrB phases formed on both steels.

Analysis results from GSAS showed the dominant phases was the FeB. Its weight fraction raised until 55 μm from the surface for ST37 steel and until 41 μm from the surface for S45C steel. The weight fraction of FeB phase showed decreasing as long as the increasing weight fraction of Fe2B and CrB phases. The crosssection boride layers microhardness ranged from 1300-1800HV for both steels. The boride layers microhardness from top of the surface ranged from 750-4500HV for both steels. The highest microhardness from top of the surface for both steels identified at the highest weight fraction of the FeB phase. The boride layers microhardness was relatively decreasing but it was still higher than the matrix microhardness and the CrB phase still identified. We can say that the boride layers microhardness from the outer surface until 50 μm is influence by the FeB phase. The boride layers microhardness below 50 μm is more influenced by the CrB phase."

"[ABSTRAKFe-Cr adalah paduan yang memiliki ketahanan temperatur tinggi danpotensial digunakan sebagai interkonektor pada sel bakar (SOFC=solid oxide fuelcell). Sintesis paduan Fe-Cr terus dikembangkan untuk mendapatkan metode yangefektif, dan efisien. Metode sintesis paduan Fe-Cr yang ada sekarang ini adalahmetode peleburan, metalurgi serbuk ataupun metode pemaduan mekanik. Metodemetodetersebut memiliki kelemahan misalnya paduan yang tidak homogen,terdapat oksida, proses panjang dan membutuhkan waktu lama. Untukmeminimumkan permasalahan ini, adalah penting untuk menghasilkan paduanmikro Fe-Cr yang memiliki kestabilan fasa dan sifat mekanis baik. Metodeultrasonik dapat dimanfaatkan untuk sintesis paduan mikro homogen melaluipenggunaan gelombang suara ultrasonik. Gelombang suara ultrasonikmenghasilkan gelembung-gelembung kavitasi, setiap runtuhan kavitasi dapatdianggap sebagai reaktor mikro yang mampu menghasilkan temperatur sekitar4737 oC dan tekanan sekitar 1000 atm dan yang terbentuk dengan sangat cepat,serta menghasilkan gelombang kejut. Dengan demikian metode ultrasonik dapatdimanfaatkan dalam pembuatan paduan mikro Fe-Cr yang homogen serta tanpaoksida dan diharapkan bisa mengatasi kelemahan metode pembuatan paduanberbasis 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 waktuterhadap partikel prekursor (Fe, Cr), kemudian terhadap campuran partikelprecursor untuk mendapatkan paduan mikro Fe-Cr. Kemudian dilakukanpembuatan bongkah paduan Fe-Cr dari partikel hasil perlakuan ultrasonik melaluikompaksi tanpa lubrikan dan sintering dalam kapsul kaca kuarsa. Karakterisasiyang dilakukan adalah menggunakan Scanning Electron Microscopy (SEM)terhadap partikel precursor hasil rekayasa ultrasonic. Untuk partikel campuranprekursor Fe-Cr hasil perlakuan ultrasonik karakterisasi dilakukan menggunakanSEM-EDS (Energy Dispersive Spectroscopy), X-Ray Diffraction (XRD) disertaianalisis dengan metode Rietveld, Transmission Electron Microscopy-SelectedArea Electron Diffraction (TEM-SAED). Untuk bongkah Fe-Cr hasil konsolidasidengan menggunakan SEM-EDS, XRD disertai analisis dengan metode Rietveld,pengukuran densitas sebenarnya, pengujian kekerasan Vickers. Efek perlakuanultrasonik terhadap partikel Fe adalah pengurangan ukuran, penyatuan, danaglomerasi. Setelah perlakuan ultrasonik 40 jam terjadi peningkatan ukuranpartikel Fe (>2μm). Terhadap partikel Cr memberikan efek erosi permukaan,pengurangan ukuran dan pemecahan partikel aglomerasi. Partikel Cr aglomerasiterurai sepenuhnya menjadi partikel Cr kecil (< 2 m) setelah 63 jam. Terhadapcampuran 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 paduanmikro Fe-Cr diawali pada ukuran partikel Fe ataupun Cr < 2m. Bongkah paduan mikro Fe-Cr yang diperoleh adalah homogen dan tanpa oksida, dengankarakteristik densitas melalui sintering dua tahap yaitu tipe O = 8.655 gr/cm3, tipeB=8.179 gr/cm3, dan tipe A=8.196 gr/cm3, dan melalui proses sintering satu tahaptipe O = 7.678 gr/cm3, tipe B=7.587gr/cm3, dan tipe A=7.092 gr/cm3. Kekerasanbongkah Fe-Cr terbesar melalui sintering satu tahap yaitu 88 VHN adalah tipe B,sementara terbesar dua tahap yaitu 81 VHN adalah tipe A. Proses perlakuanultrasonik memberikan dampak positif baik dari sisi waktu proses maupunkualitas hasil paduan Fe-Cr. Dengan demikian metode ultrasonik bisa diandalkansebagai alternatif dalam pembuatan paduan berbasis Fe untuk mengatasi kendalahomogenisasi dan oksidasi yang dihadapi pada metode saat ini.;

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ABSTRACTFe-Cr alloys have the potential for use as an interconnection material forsolid 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 amethod that is both effective and efficient. Presently, the synthesis of Fe-Cr alloysinclude the casting, the powder metallurgy, and the mechanical alloying method.These methods have several drawbacks such as inhomogeneity in the resultingproducts, oxidation, and require a very time-consuming process to accomplish. Inorder to minimize this problem, it is important to produce Fe-Cr microalloys. Fe-Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonicmethods can be used in the synthesis of homogeneous microalloys by employingthe ultrasonic sound waves. Ultrasonic sound waves will generate cavitationbubbles. Any cavitation collapse can be considered as a micro reactor in which atemperature of about 4737 oC and a pressure of about 1000 atm a very rapidlycreated, thereby generating a shock wave. Thus, the ultrasonic method can beused in producing homogeneous and free-oxide Fe-Cr microalloys and can beexpected to overcome the limitations imposed by the current methods. In thiswork the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of20 kHz in toluene liquid is presented. In the synthesis procedure, the proceduresteps followed were: (1) the treatment of precursor particles (Fe, Cr) throughultrasonic method with a time-variation, followed by (2) the same time-varyingultrasonic treatment on the admixture of these specially prepared precursorparticles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantlesscompaction method was employed on these precursor particles admixturefollowed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy.Observations of the specially prepared precursor particles using ultrasonictechnique were carried out by scanning electron microscopy (SEM) method.Observation of the precursor mixture of Fe-Cr particles mixture treatedultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy)apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysismethod, and transmission electron microscopy (TEM)-selected area electrondiffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS,XRD accompanied by analysis by the Rietveld method, true densitymeasurement, and Vickers microhardness testing. Ultrasonic treatment has causedFe particles to form agglomerations, an interparticles neck formation, and a fusingamong the particles. The size of the Fe particles increased (>2μm) after 40 hourstreatment. The agglomerated Cr particles experienced fragmentation, surfaceerosion, and reduction of particle size. The agglometrated Cr particles fullydisintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixtureof Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, formingcompletely (after ultrasonic treatment for 20 hours) and partially (after ultrasonictreatment 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 andoxide-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 densityis 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatestmicrohardness number of 88 VHN is of type B (one-step sintering), and of 81VHN is of type A (two-step sintering). The ultrasonic treatment process has apositive impact, with respect to both of quality and time-consumption to finish theFe-Cr alloying process. Therefore the ultrasonic method can be relied upon as analternative method in the production of Fe-based alloys to solve problems inhomogenization and oxidation encountered in current methods;Fe-Cr alloys have the potential for use as an interconnection material forsolid 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 amethod that is both effective and efficient. Presently, the synthesis of Fe-Cr alloysinclude the casting, the powder metallurgy, and the mechanical alloying method.These methods have several drawbacks such as inhomogeneity in the resultingproducts, oxidation, and require a very time-consuming process to accomplish. Inorder to minimize this problem, it is important to produce Fe-Cr microalloys. Fe-Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonicmethods can be used in the synthesis of homogeneous microalloys by employingthe ultrasonic sound waves. Ultrasonic sound waves will generate cavitationbubbles. Any cavitation collapse can be considered as a micro reactor in which atemperature of about 4737 oC and a pressure of about 1000 atm a very rapidlycreated, thereby generating a shock wave. Thus, the ultrasonic method can beused in producing homogeneous and free-oxide Fe-Cr microalloys and can beexpected to overcome the limitations imposed by the current methods. In thiswork the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of20 kHz in toluene liquid is presented. In the synthesis procedure, the proceduresteps followed were: (1) the treatment of precursor particles (Fe, Cr) throughultrasonic method with a time-variation, followed by (2) the same time-varyingultrasonic treatment on the admixture of these specially prepared precursorparticles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantlesscompaction method was employed on these precursor particles admixturefollowed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy.Observations of the specially prepared precursor particles using ultrasonictechnique were carried out by scanning electron microscopy (SEM) method.Observation of the precursor mixture of Fe-Cr particles mixture treatedultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy)apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysismethod, and transmission electron microscopy (TEM)-selected area electrondiffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS,XRD accompanied by analysis by the Rietveld method, true densitymeasurement, and Vickers microhardness testing. Ultrasonic treatment has causedFe particles to form agglomerations, an interparticles neck formation, and a fusingamong the particles. The size of the Fe particles increased (>2μm) after 40 hourstreatment. The agglomerated Cr particles experienced fragmentation, surfaceerosion, and reduction of particle size. The agglometrated Cr particles fullydisintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixtureof Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, formingcompletely (after ultrasonic treatment for 20 hours) and partially (after ultrasonictreatment 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 andoxide-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 densityis 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatestmicrohardness number of 88 VHN is of type B (one-step sintering), and of 81VHN is of type A (two-step sintering). The ultrasonic treatment process has apositive impact, with respect to both of quality and time-consumption to finish theFe-Cr alloying process. Therefore the ultrasonic method can be relied upon as analternative method in the production of Fe-based alloys to solve problems inhomogenization and oxidation encountered in current methods, Fe-Cr alloys have the potential for use as an interconnection material forsolid 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 amethod that is both effective and efficient. Presently, the synthesis of Fe-Cr alloysinclude the casting, the powder metallurgy, and the mechanical alloying method.These methods have several drawbacks such as inhomogeneity in the resultingproducts, oxidation, and require a very time-consuming process to accomplish. Inorder to minimize this problem, it is important to produce Fe-Cr microalloys. Fe-Cr microalloys exhibit phase stability and good mechanical properties. Ultrasonicmethods can be used in the synthesis of homogeneous microalloys by employingthe ultrasonic sound waves. Ultrasonic sound waves will generate cavitationbubbles. Any cavitation collapse can be considered as a micro reactor in which atemperature of about 4737 oC and a pressure of about 1000 atm a very rapidlycreated, thereby generating a shock wave. Thus, the ultrasonic method can beused in producing homogeneous and free-oxide Fe-Cr microalloys and can beexpected to overcome the limitations imposed by the current methods. In thiswork the formation of Fe-Cr microalloys by ultrasonic treatment at a frequency of20 kHz in toluene liquid is presented. In the synthesis procedure, the proceduresteps followed were: (1) the treatment of precursor particles (Fe, Cr) throughultrasonic method with a time-variation, followed by (2) the same time-varyingultrasonic treatment on the admixture of these specially prepared precursorparticles in order to obtain the Fe-Cr microalloys, and (3) finally, the lubricantlesscompaction method was employed on these precursor particles admixturefollowed by sintering process inside quartz tubes to obtain a bulk of Fe-Cr alloy.Observations of the specially prepared precursor particles using ultrasonictechnique were carried out by scanning electron microscopy (SEM) method.Observation of the precursor mixture of Fe-Cr particles mixture treatedultrasonically was performed using a SEM-EDS (energy-dispersive spectroscopy)apparatus, a X-Ray diffractometer and accompanied by the Rietveld analysismethod, and transmission electron microscopy (TEM)-selected area electrondiffraction (SAED) apparatus. The bulk of Fe-Cr alloy were observed using SEMEDS,XRD accompanied by analysis by the Rietveld method, true densitymeasurement, and Vickers microhardness testing. Ultrasonic treatment has causedFe particles to form agglomerations, an interparticles neck formation, and a fusingamong the particles. The size of the Fe particles increased (>2μm) after 40 hourstreatment. The agglomerated Cr particles experienced fragmentation, surfaceerosion, and reduction of particle size. The agglometrated Cr particles fullydisintegrated into Cr microparticles (<2μm) after 63 hours treatment. The mixtureof Fe-Cr forming cohesive (Fe-Fe, Cr-Cr) and adhesive (Fe-Cr) particles, formingcompletely (after ultrasonic treatment for 20 hours) and partially (after ultrasonictreatment 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 andoxide-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 densityis 7.678 for type O, is 7.587 for type B, and is 7.092 for type A. The greatestmicrohardness number of 88 VHN is of type B (one-step sintering), and of 81VHN is of type A (two-step sintering). The ultrasonic treatment process has apositive impact, with respect to both of quality and time-consumption to finish theFe-Cr alloying process. Therefore the ultrasonic method can be relied upon as analternative method in the production of Fe-based alloys to solve problems inhomogenization and oxidation encountered in current methods]"

"Penelitian ini bertujuan untuk mengevaluasi pengaruh durasi penyinaran menggunakan LED dan pemanasan awal menggunakan Micerium ENA Heat terhadap depth of cure resin komposit bulk-fill. Alat dan bahan: Enam puluh spesimen Filtek Bulk-Fill Posterior Restoratives ketebalan 4 mm dan diameter 3 mm; tanpa dan dengan pemanasan awal pada temperatur 39 C dibagi ke dalam 3 kelompok sesuai dengan durasi penyinaran 5 detik, 10 detik, dan 15 detik. Spesimen dipolimerisasi menggunakan LED Curing Unit 3MTM Elipar, 1.200 mW/cm2 dan diuji kekerasan mikro menggunakan Vickers Microhardness Tester Shimadzu, Japan untuk menghitung nilai depth of cure. Data yang diperoleh dianalisis menggunakan uji statistik Kruskall-Wallis dan Post-Hoc Mann Whitney-U.Hasil: Adanya perbedaan yang tidak bermakna p ge;0,05 untuk nilai depth of cure pada keenam kelompok tanpa dan dengan pemanasan awal. Walaupun nilai depth of cure tersebut tidak bermakna namun telah mencapai nilai minimum yaitu ge; 80. Selain itu terdapat perbedaan yang bermakna p.

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Aim Evaluate the influence of different exposure time and pre heating on its depth of cure of bulk fill composite. Methods Sixty cylinder shaped specimens of Filtek Bulk Fill Posterior Restoratives 4 mm of thickness x 3 mm of diameter with and without pre heating at 39 C were divided into 3 subgroups according to exposure times 5, 10, and 15. All specimens were polymerized using LED Curing Unit 3MTM Elipar, 1.200 mW cm2 and tested using Vickers Microhardness Tester Shimadzu, Japan to determine its microhardness for calculating its depth of cure. Data were statistically analyzed using Kruskall Wallis and Post Hoc Mann Whitney U test.

Results A no significant differences p ge 0,05 in depth of cure amongst the six groups of non preheated and preheated bulk fill composite. However, all of the groups have reached a minimum value of ge 80 depth of cure. Moreover, there is a significant differences in microhardness in all of the six groups of non preheated and preheated bulk fill composite and between 5 and 15 of exposure times in both groups. Conclusion Exposure times and pre heating at 39 C had an influence on microhardness of bulk fill composite."

"Latar Belakang: Proses PILP adalah proses remineralisasi yang menggunakan makromolekul bermuatan, yakni polyaspartic acid, untuk menstabilkan ion calcium phosphate dalam larutan tersaturasi, dan mencegah nukleasi spontan serta presipitasi mineral. Penambahan ion fluoride pada proses ini akan membentuk kristal fluorapatite yang memiiki kekerasan lebih tinggi dari hidroksiapatit. Tujuan:Penelitian ini bertujuan untuk mengetahu pengaruh penambahan fluoride dalam larutan remineralisasi melalui proses PILP terhadap kekerasan email. Metode: 25 sampel gigi dibagi menjadi 5 kelompok. Kelompok 1 (email normal) sebagai kontrol positif, kelompok 2 (email terdemineralisasi) sebagai kontrol negatif, kelompok 3 email yang diremineralisasi melalui proses PILP, kelompok 4 email yang diremineralisasi melalui proses PILP dengan penambahan fluoride 5 ppm, kelompok 5 email yang diremineralisasi melalui proses PILP dengan penambahan fluoride 25 ppm. Seluruh sampel disimpan dalam inkubator pada suhu 370C selama 14 hari. Selanjutnya dilakukan uji kekerasan mikro untuk melihat kekerasan email. Data yang diperoleh dianalisis secara statistik dengan one-way ANOVA dan uji Post Hoc Tamhane. Hasil: Terdapat perbedaan bermakna kekerasan mikro email setelah diremineralisasi melalui proses PILP tanpa dan dengan penambahan fluoride 5 ppm dan 25 ppm. Kesimpulan:Remineralisasi melalui proses PILP dengan penambhan fluoride 5 ppm memiliki kekerasan mikro yang lebih tinggi dibandingkan tanpa penambahan fluoride dan dengan penambahan fluoride 25 ppm.

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Background: PILP process is a remimineralization used charged macromolecule, polyaspartic acid, to stabilize calcium and phophate ion in order to prevent mineral spontaneus nucleation and precipitation. Fluoride was addedto form fluorapatite crystals which have a higer microhardness than hydroxyapatite. Objective: To determine the effect of adding fluoride in remineralization solution through the PILP process on enamel microhardness. Methods: 25 teeth were divided into 5 groups. Group 1 (normal enamel) as a positive control, group 2 (demineralized enamel) as a negative control, group 3 demineralized enamel which remineralized through PILPprocess, group 4 demineralized enamel which remineralized through PILP process with 5 ppm fluoride, group 5 demineralized enamel which remineralized through PILP process with 25 ppm fluoride. All samples were stored in an incubator at 370C for 14 days. Vicker's microhardness test was performed to see enamel microhardness. The data were statistically analyzed with one-way ANOVA and Tamhane Post Hoc Test. Result: There is a difference between enamel microhardness after being remineralized through PILP process without and with 5 and 25 ppm fluoride.Conclusion: Remineralization via PILP process with addition of 5 ppm fluoride has a higher microhardness value than without and with 25 ppm fluoride."

"ABSTRAKLatar belakang: Karies gigi merupakan penyakit multifaktor yang disebabkan oleh interaksi komplek biofilm dengan sumber karbohidrat yang menempel di permukaan gigi. Salah satu proses yang terjadi pada email gigi untuk terbentuknya karies adalah proses demineralisasi gigi yang terjadi secara dominan dibandingkan dengan proses remineralisasi. Upaya yang dapat dilakukan untuk mencegah karies adalah dengan pengaplikasian bahan remineralisasi seperti propolis fluorida dan natrium fluorida. Penggunaan bahan remineralisasi ini dapat meningkatkan kekerasan email. Tujuan: Membandingkan peningkatan kekerasan email setelah pengaplikasian bahan remineralisasi propolis fluorida dan natrium fluorida. Metode: 32 sampel gigi premolar dibagi menjadi kelompok propolis fluorida dan natrium fluorida. Seluruh spesimen ditanam di dalam pipa paralon dan dilakukan penghalusan dan pemolesan. Seluruh spesimen dilakukan tes kekerasan awal. Kemudian dilakukan demineralisasi dengan menggunakan Buavita® (pH 3,85). Setelah itu spesimen diukur kekerasannya, kemudian diaplikasikan propolis fluorida dan natrium fluorida dan direndam dalam saliva buatan selama 3 hari. Setelah itu dilakukan pengukuran kekerasan akhir dan dibandingkan secara statistik. Hasil: Natrium Fluorida lebih efektif dalam meningkatkan kekerasan email dibandingkan dengan Propolis Fluorida, dan juga terdapat perbedaan bermakna kekerasan gigi yang telah didemineralisasi dan kekerasan email gigi setelah diaplikasi bahan remineralisasi. Kesimpulan: Terdapat perbedaan bermakna antara peningkatan kekerasan email pada pengaplikasian propolis fluorida dan natrium fluorida.

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ABSTRACT

Background: Dental caries is a multifactorial disease caused by the interaction of the biofilm complex with carbohydrate sources attached to the surface of the teeth. One process that occurs in tooth enamel for caries formation is the process of tooth demineralization that occurs predominantly compared to the remineralization process. Efforts that can be made to prevent caries are by applying remineralization materials such as propolis fluoride and sodium fluoride. The use of remineralization materials can increase the hardness of email. Objective: Compares increased enamel hardness after application of propolis fluoride and sodium fluoride remineralization materials. Methods: 32 premolar tooth samples were divided into propolis fluoride and sodium fluoride groups. All specimens were planted in paralon pipes and finalized and polished. All specimens were subjected to initial hardness tests. Then demineralization was done using Buavita® (pH 3.85). After that the specimens were measured hardness, then propolis fluoride and sodium fluoride were applied and soaked in artificial saliva for 3 days. After that, the final violence measurement and compared statistically. Results: Sodium Fluoride is more effective in increasing the hardness compared with Propolis Fluoride, and there were also significant differences in demineralized tooth enamel and tooth enamel hardness after remineralization.. Conclusion: There is a significant difference between increasing enamel hardness when applying propolis fluoride and sodium fluoride."