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"Bahan organik dan bahan an-organik sangat berbeda dalam banyak hal, sehingga sulit untuk terbentuk ikatan adhesi yang sangat kuat diantara permukaan keduanya. Adhesion promoter bekerja pada permukaan material organik dan an-organik untuk menggabungkan keduanya membentuk suatu ikatan yang kuat. Bila bekerja secara optimal, adhesion promoter dapat menggabungkan kedua material organik dan anorganik secara fisik maupun kimia menjadi sebuah ikatan kohesi yang sangat kuat. Telah banyak penelitian-penelitian terdahulu yang membahas mengenai penggunaan beberapa silane sebagai adhesion promoter pada berbagai aplikasi.Pada penelitian ini penulis membandingkan beberapa jenis silane sebagai adhesion promoter yang digunakan untuk aplikasi sealant pada kaca, menganalisis pengaruh komposisi silane dalam masing-masing campuran dan waktu curingnya terhadap peningkatan daya adhesi dan daya tahan kekuatan adhesif terhadap pengaruh lingkungan, dengan metode uji peel test, dan simulasi Thermal-Humidity Cycle dan Accelerated Weathering test, untuk mendapatkan komposisi silane yang paling tepat yang dapat memenuhi standar otomotif. Didapat γ-Glycidoxypropyltrimethoxysilane memiliki peningkatan kekuatan adhesif yang lebih tinggi pada kondisi normal, namun γ- Isocyanatopropyltriethoxysilane memiliki daya tahan yang lebih baik terhadap pengaruh lingkungan.

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Organic and inorganic materials are very different in many ways, it is very difficult to form adhesive bond between these two materials. Adhesion promoter / primer works between the surfaces of organic material and inorganic material to joint them in order to make a strong bond. If it work optimally, adhesion promoter can joint those organic and inorganic material into strong cohesive bond structure. Many previous researches have explained the use of silane as adhesion promoter.In this work, we will compare a couple of silane type as adhesion promoter for glass sealant application, to anaylize the effect of silane content in every compunds and it?s curing time to adhesion strength enhancement, and durability of adhesive bond, using peel testing method and simulation using Thermal-Humidity Cycle dan Accelerated Weathering test,, in order to get the appropriate silane content for automotif glass sealant application. Concluded that in normal condition γ- Glycidoxypropyltrimethoxysilane increase adhesion strength better, but γ- Isocyanatopropyltriethoxysilane have better durability."

"PENDAHULUAN : Pit dan fissure sealant merupakan bahan restorasi yang sering digunakan untuk perawatan pencegahan khususnya pada permukaan oklusal gigi anak. Semua bahan restorasi yang berkontak dengan air akan mengalami 2 mekanisme: penyerapan air, yang menyebabkan pembengkakan matriks serta meningkatnya massa dan kelarutan air, terlepasnya komponen dari monomer yang tidak bereaksi dan menyebabkan berkurangnya massa.TUJUAN: Mengetahui pengaruh peningkatan waktu perendaman resin PFS terhadap penyerapan air dan kelarutan resin PFS di dalam air.ALAT & METODE: Sesuai spesifikasi ISO 4049 (2000). Delapan belas spesimen dibuat dari cetakkan (15x1mm) yang dimanipulasi sesuai petunjuk pabrik. Spesimen dimasukkan ke dalam desikator selama 1 hari (T 37 °C; 22 jam dan 23ºC ; 2 jam) ditimbang berulang kali sampai didapat massa konstan (M1). Spesimen direndam selama 1, 2 dan 7 hari di dalam akuabides kemudian dikeringkan dengan kertas penghisap dan digetarkan di udara selama 15 detik setelah itu ditimbang berulang kali sampai massa konstan didapat (M2). Kemudian spesimen dimasukkan lagi ke dalam desikator selama 2 hari (T 37 °C; 22 jam dan 23ºC ; 2 jam) x 2 dan segera ditimbang berulang kali sampai didapatkan massa konstan (M3). Nilai penyerapan air dan kelarutan bahan dari setiap spesimen dihitung menurut perubahan berat sebelum dan setelah perendaman dan pengeringan.HASIL : Dianalisis secara statistik dengan uji non-Parametrik Kruskal-Wallis dengan Post Hoc Mann-Whitney, p<0,05. Nilai penyerapan air meningkat secara signifikan seiring lamanya perendaman dan berbeda bermakna di antara setiap waktu perendaman sedangkan nilai kelarutan air meningkat tertinggi pada 1 hari perendaman dan tidak berbeda bermakna diantara setiap waktu perendaman, kecuali dengan 0 hari (kontrol).KESIMPULAN : 1) Peningkatan waktu perendaman menyebabkan peningkatan penyerapan air. 2) Peningkatan waktu perendaman berpengaruh terhadap kelarutan bahan hanya pada hari 1.

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INTRODUCTION : Pit and fissure sealant is one of the restorative material that often used as a preventive treatment, especially at occlusal surface of child dentition. All of restorative material that contact with water will experienced 2 mechanism: water sorption, which leads to swelling and mass increase and water solubility, elution of unreacted monomer which leads to a reduction of mass.

OBJECTIVE: To evaluate the effect of different time of immersion to the value of water sorption and water solubility in aquabidest.

METHOD AND MATERIALS: According to ISO (4049) specification. Eighteen disks (15 x 1 mm) of each material are prepared according to the manufacturers' instructions. Specimens are first desiccated for 1 day (T 37 °C; 22 hr dan 23ºC ; 2 hr) weigh several times until a consistent mass is obtained (M1). Specimens are immersed for 1, 2 and 7 days in aquabidest, remove then dried with absorbent paper, waved in the air for 15 second then immediately weighed after this period (M2). After that the specimen is inserted in dessicator again for 2 days (T 37 °C; 22 hr and 23ºC ; 2 hr) x 2 and weighed several times until constant mass is reached (M3). The value of water sorption and solubility of each specimen were calculated according to the change in its weight as observed before and after immersion and desiccation periods.

RESULTS: This result is analyzed statistically with nonparametric test Kruskal-Wallis with post hoc test Mann-Whitney p<0,05. The value of water sorption is increasing significantly along the time of immersion and different significantly from the other time of immersion while water solubility reach its maximum value in the first day and doesn?t different significantly with other time of immersion, except with control.

CONCLUSIONS: 1) The longer time of immersion increases the value of water sorption 2) The longer time of immersion only affect the first day value of water solubility."

"ABSTRACTFor a given sealant, successful pit and fissure sealing is principally governed by the enamel conditioning technique and the presence of moisture contamination. A new generation of hydrophilic resin sealants is reported to tolerate moisture. This study investigates the impact of Er YAG laser preconditioning and moisture contamination on the microleakage of a recent hydrophilic sealant. Occlusal surfaces of extracted human molars were either acid etched (n = 30), or successively lased and acid etched (n = 30). Ten teeth from each group were either air dried, water contaminated, or saliva-contaminated prior to sealing with UltraSeal XT hydro. Samples were inspected for penetration of fuchsin dye following 3000 thermocycles between 5 and 50 C, and the enamel sealant interfaces were observed by scanning electron microscopy (SEM). Significant differences in microleakage were evaluated using the Mann Whitney U test with Bonferroni adjustment (p = 0.05). Laser pre-conditioning significantly reduced dye penetration irrespective of whether the enamel surface was moist or dry. Microleakage of watercontaminated acid etched teeth was significantly greater than that of their air-dried or salivacontaminated counterparts. SEM analysis demonstrated good adaptation in all groups with the exception of water-contaminated acid etched teeth which exhibited relatively wide gaps. In conclusion, this hydrophilic sealant tolerates the presence of saliva, although water was found to impair its sealing ability. Laser pre-conditioning significantly decreases microleakage in all cases."

"Pendahuluan. Persentase indeks karies oklusal gigi mendekati 90 % dimana area pit & fissure gigi memiliki risiko karies 8x lebih besar daripada permukaan licin lainnya pada gigi. Resin pit & fissure sealant merupakan bahan restorasi gigi yang digunakan untuk menutup pit dan fissure oklusal gigi posterior guna mencegah karies. Oleh karena lokasi restorasi tersebut berada di dalam mulut, maka resin tersebut akan berkontak dengan saliva yang kandungan utamanya adalah air. Air tersebut akan diserap oleh matriks resin pit & fissure sealant sehingga mengakibatkan perubahan pada kekerasan permukaannya. Tujuan. Untuk menganalisa pengaruh waktu perendaman resin pit & fissure sealant di dalam air terhadap kekerasan permukaan material tersebut. Metode. Spesimen resin pit & fissure sealant (diameter 15 mm & tebal 1 mm) sebanyak 24 buah dimanipulasi sesuai petunjuk pabrik dan dibuat dengan menggunakan cetakan akrilik. Jumlah tersebut dibagi dalam 4 kelompok uji, yaitu kelompok kontrol (tidak direndam dalam air), kelompok uji perendaman 1 hari, 2 hari dan 7 hari, dimana setiap kelompok uji menggunakan 6 spesimen. Spesimen direndam dalam air akuabides 40 ml dan dimasukkan ke dalam cornic tube kemudian disimpan dalam inkubator 370C. Sebelum direndam, setiap spesimen ditimbang 3 kali dengan timbangan elektronik Shimadzu hingga diperoleh massa konstan (M1). Kemudian spesimen tersebut direndam dalam air akuabides selama 1, 2, dan 7 hari, kecuali kelompok kontrol yang langsung diuji kekerasan permukaannya dengan alat uji Vicker. Setelah direndam, spesimen ditimbang 3 kali hingga didapat massa konstan (M2). Setelah itu, spesimen diuji kekerasan permukaannya dengan alat Vicker. Indentasi pada uji kekerasan permukaan dilakukan pada 5 area untuk setiap spesimen. Hasil. Spesimen kontrol memiliki nilai kekerasan permukaan yang tertinggi. Nilai kekerasan permukaan antar kelompok spesimen yang direndam tidak menunjukkan perbedaan nilai yang signifikan. Hasil penelitian ini dianalisis secara statistik dengan menggunakan one-way ANOVA, p<0,05 berarti terdapat perbedaan bermakna nilai kekerasan permukaan antara kelompok kontrol dengan semua kelompok perendaman. Sedangkan nilai kekerasan permukaan antar tiap kelompok perlakuan tidak berbeda bermakna, dengan p>0,05. Kesimpulan. Waktu perendaman 1 hari resin pfs dalam air menyebabkan penurunan kekerasan permukaan secara signifikan. Namun, waktu perendaman selama 2 & 7 hari tidak menunjukkan penurunan kekerasan permukaan yang signifikan.

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Introduction. Percentage of occlusal caries teeth approximately 90 % and pit & fissure tooth have caries risk about 8 times than other smooth surface of tooth. Pit and fissure sealant resin is tooth restorative material which is used to seal pit and fissure on occlusal of posterior tooth to prevent caries. Due to the location of restoration in oral cavity, it will contact with saliva which have major content is water. Water will be absorbed by resin`s matrix therefore cause changing of surface hardness.

Objectives. The purpose of this research is to analyze effect of immersion time to the surface hardness of pit & fissure sealant resin.

Methods. 24 specimens pit & fissure sealant resin (15 mm in diameter & 1 mm in thick) are manipulated according to factory manual in acrylic mould. The number of specimens is divided to 4 groups of specimen. These are control group (doesn`t immersed in water), specimen groups which is immersed for 1 day, 2 days and 7 days. Each of these group uses 6 specimens. The specimens are immersed in 40 ml aquabidest and inserted to cornig tube and then storage in incubator 370C. Before specimens is immersed in water, it is weighed 3 times by Shimadzu electronic balance until mass constant is regained (M1). After that, the specimens are immersed in aquabidest for 1 day, 2 days and 7 days, except control group which is surface hardness tested immediately with Vicker surface hardness tester. After the specimens are immersed in aquabidest, it is weighed 3 times until mass constant is regained. And then, the specimens is tested for Vicker surface hardness. Indentation of surface hardness test have done on 5 areas for each specimen.

Results. Specimens control have the highest value of surface hardness. Surface hardness value between immersed specimen groups doesn`t show different value significantly. This result is analyzed statistically with one-way ANOVA, p<0,05. According it, there were significant difference among control group and all of immersed groups. Meanwhile no significant difference in surface hardness value among immersed groups (p>0,05). Conclusion. Immersion of pit & fissure sealant resin in water for 1 day cause significantly decreasing of surface hardness but immersion time for 2 & 7 days doesn`t significantly decreased. "

"Joint sealant is used for concrete pavement joints. To fulfill jpint sealant requirements, laboratory tests have been carried out except weathering test, therefore for this purpose, experiments by simulation on concrete pavement is required in order to conform to all requirements for use in sealing joints in concrete pavements..."

"Pit Fissure Sealant berbahan resin merupakan salah satu produk pencegahan karies. Pada penelitian sebelumnya, ditunjukkan adanya pelepasan komponen dan material tersebut ke lingkungannya yang menimbulkan respon hipersensitifitas. Tujuan : untuk mengetahui biokompatibilitas dari Resin Pit Fissure Sealant terhadap sel keratinosit kulit yang dicerminkan dari viabilitas sel HaCaT. Material dan Metode: Spesimen Resin Pit & Fissure Sealant dibuat pada cetakan akrilik (N=18; diameter 15mm; ketebalan 1mm) menurut ISO 4049 dan dipolimerisasi dengan UV dari QTH (Quartz Tungsten Halogen) ( = 400 nm). Spesimen dipersiapkan dan disterilisasi untuk menghindari kontaminasi dari bakteri atau jamur. Setelah itu, spesimen direndam dalam DMEM (5mL) dan disimpan dalam inkubator (370C) selama 1, 2, dan 7 hari. Kultur sel dipersiapkan pada 96 well dan diinkubasi selama 24 jam. Rendaman spesimen dipaparkan ke setiap well dan diuji tingkat viabilitas selnya menggunakan MTT assay. Tingkat viabilitas sel diukur dengan microplate reader = 490 nm. Signifikansi diukur dengan metode analisis ragam satu arah Anova. Hasil : Viabilitas sel menurun pada hari pertama dan setelah hari kedua. Kesimpulan : Waktu perendaman mempengaruhi viabilitas sel, tetapi masih cukup aman untuk digunakan untuk perawatan gigi.

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Resin based Pit Fissure Sealant is one of dental caries prevention product. Previous research of resin showed that some components leached into aqueous environment and cause hypersensitivity responses.

Objectives: To observe the biocompatibility of Resin Pit Fissure Sealant due to skin keratinocytes which is determined by viability of HaCaT Cell lines.

Material & Methods : Resin based Pit Fissure Sealant were made in acrylic mould (N= 18; diameter 15mm; thickness 1mm) according to ISO 4049 and polymerized by UV light from QTH (Quartz Tungsten Halogen) ( = 400 nm). Specimen were prepared and sterilized to avoid contamination from bacterial or germs. After that, Specimens were immersed in DMEM (5mL) and stored in incubator (370C) for 1, 2, and 7 days. Cell Culture were prepared into 96 well and stored in incubator for 24 hours. The elution of specimens was exposed into every well, and examined the viability of cells by MTT assay. Viability Cell were counted in 490 nm microplate reader. Significance were measured by One Way Anova.

Results : The viability of HaCaT Cell Lines were decreased in first and after second days.

Conclusion : The elution time of Resin based Pit Fissure Sealant affect the viability of HaCat Cell line, but still safe to be used in dental clinic."

"Magnesium (Mg) merupakan logam ringan dan dapat diserap tubuh melalui proses degradasi atau bersifat biodegradable. Namun Magnesium dan paduannya mengalami degradasi yang sangat cepat di dalam lingkungan fisiologis akibatnya kekuatan mekanik dari implan akan menurun. Untuk meningkatkan ketahanan korosi dari paduan magnesium dapat dilakukan dengan metode anodizing. Lapisan oksida yang dihasilkan dari proses anodizing memiliki banyak retakan dan pori pada permukaannya. Retakan dan pori ini dapat ditutup melalui metode sealing beeswax-colophony. Proses anodizing dilakukan pada tegangan konstan 5 volt dalam elektrolit 0.5 M Na3PO4 pada suhu 30°C ± 1°C dengan variasi waktu 10, 20, dan 30 menit. Pada waktu 10, 20, dan 30 menit terukur tebal lapisan 6, 14, dan 16 μm. Optimasi waktu anodizing dihasilkan pada anodizing 20 menit. Untuk mengetahui laju korosi paduan magnesium yang telah di anodizing dan sealing dilakukan dengan uji hilang berat (invitro) selama 14 hari dalam larutan 0,9% NaCl pada suhu 37°C. Hasil uji hilang berat divalidasi dengan uji potentiodynamic polarization. Hasil uji hilang berat yang menunjukkan laju korosi dari substrat; anodizing; substrat + beeswax-colophony sealing; anodizing + hidrotermal sealing; anodizing + beeswax-colophony sealing berturut-turut yaitu 7,91; 6,26; 5,0; 6,06; dan 3,30 mmpy. Hasil uji polarisasi menunjukkan peningkatan ketahanan korosi yang diperlihatkan oleh kenaikan potensial korosi untuk substrat; anodizing; substrat + beeswax-colophony sealing; anodizing + hidrotermal sealing; anodizing + beeswax-colophony sealing berturut-turut adalah -1.49, -1.57, -1.54, -1.43, dan -1,17 VAg/AgCl dan penurunan arus korosi berturut-turut 5.72x10-4, 3.40x10-5, 2.54x10-8, 2.19x10-5 , dan 3.19x10-8 A/cm2. Hasil tersebut menunjukkan bahwa perlakuan anodizing dan sealing dengan beeswax-colophony terbukti dapat meningkatkan ketahanan korosi paduan AZ31 2 kali lipat.

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Magnesium (Mg) is the light metals and absobable materials by the human body through a process of degragradation known as biodegradable. However, Mg and its alloys has a rapid corrosion rate in physiological environtment causes reduction of mechanical properties of implants. Anodizing is widely used to increase corrosion resistance of magnesium alloys. The oxide layer produced while anodizing process has many cracks and porous on its surface. Cracks and porous could covered by beeswax-colophony sealing method. The anodization process was carried out at constant voltage 5 volt in electrolyte of 0.5 M Na3PO4 at 30 ° C ± 1 ° C with variations of time 10, 20, and 30 minutes. The thickness of layer was measured at 10, 20, and 30 minutes are 6, 14, 16 μm respectively. Anodizing time optimization was obtained at 20 minutes. to determine the corrosion rate of anodized and sealed magnesium alloy was carried out by in-vitro test for 14 days on 0.9% NaCl solution at 37 ° C. The results of the weight loss test were validated by potentiodynamic polarization test. The weight loss test results exhibits the rate of corrosion of the substrate, anodizing; substrate + beeswax-colophony sealing; anodizing + hydrothermal sealing; anodizing + beeswax-colophony sealing are 7.91, 6.26, 5.0, 6.06, and 3.30 mmpy respectively. The results of corrosion on AZ31 show by increased corrosion potential, -1.49, -1.57, -1.54, -1.43, and -1.17 VAg/AgCl and decreased corrosion currents, 5.72x10-4, 3.40x10-5, 2.54x10-8, 2.19x10-5, and 3.19x10-8 A/cm2 on the substrate; anodizing; substrate + beeswax-colophony sealing; anodizing + hydrothermal sealing; anodizing + beeswax-colophony sealing. These results prove anodizing and coatings increase corrosion resistance of AZ31 twice.

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