Menyelami Ilmu Biologi Molekuler dan Genetika dari Buku Genomes 3

Buku Genomes 3 merupakan buku yang sangat dianjurkan untuk dibaca oleh ilmuwan di era yang sangat pesat akan perkembangan ilmu pengetahuan dan teknologi, khususnya dibidang ilmu molekuler biologi dan genetika. Penulisan buku ini telah disusun dengan sangat hati hati agar mudah dipahami oleh pembaca dan dilengkapi dengan CD-ROM yang dapat dilihat dalam dua format, power point dan JPEG

Treatment of temporomandibular joint trauma following odontectomy

Temporomandibular Joint Disorder (TMD) is a non-dental musculoskeletal disorder that has a complex and multifactorial etiology. The most frequent symptoms are pain in the masticatory muscles, in front of the ears, and in the temporomandibular joint (TMJ); this disorder can also be accompanied by clicking sounds and locking. This study aimed to present a case report of temporomandibular joint trauma following odontectomy. A 22-year-old patient came with some complaints, namely pain in the TMJ, a clicking sound when opening and closing the mouth, and limited mouth opening. The symptoms started when the patient underwent odontectomy on all the four third molars, causing tightness around the jaw, pain, and clicking. However, she did not seek any treatment for these conditions until the pain became worse and disturbed her activities. The patient had to deal with limited mouth opening and severe migraines up to twice a day. During an examination, the patient was able to open her mouth without pain only 25 mm in width, with a maximum mouth opening of 35 mm. The therapy was done by constructing a 4-mm stabilization splint and educating the patient on how to reduce the pain. In fact, 2 months after the treatment and the use of stabilization splints, her complaints of TMJ pain and clicking sounds decreased, her mouth opening increased, and the migraines never came back. In this case, non-invasive treatment as the first-line therapy in patients with disc displacement with reduction and arthralgia can reduce the joint pain symptoms, and some of the symptoms have even disappeared

MENYELAMI ILMU BIOLOGI MOLEKULER DAN GENETIKA DARI BUKU GENOMES 3

Buku Genomes 3 merupakan buku yang sangat dianjurkan untuk dibaca oleh ilmuwan  di era yang sangat pesat akan perkembangan ilmu pengetahuan dan teknologi, khususnya dibidang ilmu molekuler biologi dan genetika. Penulisan buku ini telah disusun dengan sangat hati hati  agar mudah dipahami oleh pembaca dan dilengkapi dengan CD-ROM yang dapat dilihat dalam dua format, power point dan JPEG

Penggunaan gigi tiruan untuk rehabilitasi perubahan otot wajah akibat kehilangan gigi

Perubahan dimensi jaringan lunak dan tulang paska pencabutan gigi dapat menyebabkan perubahan estetika wajah. Hal ini disebabkan karena gigi berfungsi untuk mendukung otot wajah, tanpa dukungan gigi wajah terlihat berkerutdan lebih tua. Perubahan yang terlihat pada wajah meliputi lipatan nasolabial menjadi lebih dalam, sudut mulut turun, bibir menipis, bibir atas terlihat panjang dan hidung terlihat lebih besar akibat hilangnya dukungan bibir atas. Usaha yang dilakukan untuk memperbaiki keadaan tersebut adalah pembuatan gigi tiruan yang dapat mendukung kembali otot wajah. Tujuan artikel ini yaitu untuk menginformasikan akibat kehilangan gigi pada perubahan otot wajah dan usaha memperbaikinya menggunakan gigi tiruan. Seorang wanita usia 67 tahun datang ke RSGM Prof Soedomo dengan keluhan merasa rendah diri karena wajah terlihat lebih tua akibat hilangnya seluruh gigi pada rahang atas dan bawah. Tatalaksana kasus 1). Anamnesa, 2). Pemeriksaan klinis dan radiografis, 3). Pencetakan rahang, 4). Pembuatan gigi tiruan lengkap (GTL) kerangka logam untuk rahang atas dan rahang bawah, 5). Insersi GTL. Pembuatan GTL pada rahang atas dan rahang bawah yang sesuai dengan kaidah pembuatan gigi tiruandapat memperbaiki estetika akibat hilangnya dukungan otot wajah. Kesimpulan dari penggunaan GTL konvensional yang dibuat sesuai dengan prinsip prostodontik yang ditetapkan dapat mengembalikan estetika otot wajah akibat kehilangan gigi

Sp6 downregulation of follistatin gene expression in ameloblasts

Sp6 is a member of the Sp family of transcription factors that regulate a wide range of cellular functions, such as cell growth and differentiation. Sp6, also called epiprofin, is specifically expressed in tooth germ, limb bud, and hair follicle, but there is little information on its function. To investigate the possible role of Sp6 in tooth development, first we established an Sp6- overproducing clone, CHA9, and analyzed the features of the cell, including cell proliferation and gene expression. The parental cells of CHA9 are the ameloblast-lineage G5 cells that we previously established from rat dental epithelia of lower incisor. Sp6 overproduction accelerated cell proliferation and induced the expression of ameloblastin mRNA, a marker of ameloblast differentiation. Second, we performed genome-wide screening of Sp6 target genes by microarray analysis. Out of a total 20,450 genes, 448 genes were up-regulated and 500 genes were down-regulated by Sp6. We found the expression of follistatin, a BMP antagonist, to be 22.4-fold lower in CHA9 than in control cells. Transfection of the Sp6-antisense construct into CHA9 cells restored follistatin expression back to equivalent levels seen in control cells, indicating that Sp6 regulates follistatin gene expression in ameloblasts. Our findings demonstrate that the follistatin gene is one of the Sp6 target genes in ameloblasts and suggest that Sp6 promotes amelogenesis through inhibition of follistatin gene expression

Dealing with the high-risk potential of COVID-19 cross-infection in dental practice

The World Health Organization reported that the SARS-CoV-2 virus has infected more than 5 million people around the world. Dental care providers and health care professionals need to be aware of the high-risk potential of crossinfection since the routes of virus transmission commonly happen through droplets and aerosols. This review aimed at collecting essential knowledge about the COVID-19 needed by dental practitioners. The review focused on the oral involvement in COVID-19, the role of oral transmission as the high-risk potential of cross-infection and recommended strategies to minimize the risk of cross-infection in dental practice. We searched all the published clinical features from PubMed, Google Scholar, Scopus and hand searched library online databases, from January 2015 until May 2020. Keywords used were “COVID-19”, “Dentistry”, “Dental protection”, “Cross-contamination”, “Aerosol and non aerosol”, and ”Povidone-iodine” with their combinations. We identified 52 articles to review after the initial selection with inclusion and exclusion criteria. Results showed use of topical applications of povidine-iodine and viricidal mouthwash could significantly reduce the high-risk of cross-infection from dentistry patients who are asymptomatic with COVID-19 infection. Further safeguards include suspending all non-emergency procedures temporarily and closely screening patients for symptoms which may be suspected to be COVID-19 infection

Msx2 and Sp6 Regulate Follistatin

Background: Ameloblasts are epithelially derived cells responsible for enamel formation through a process known as amelogenesis. Amongst the several transcription factors that are expressed during amelogenesis, both Msx2 and Sp6 transcription factors play important role. Msx2 and Sp6 mouse mutants, exhibit similar amelogenesis defects, namely enamel hypoplasia, while humans with amelogenesis imperfecta (AI) carry mutations in the human homologues of MSX2 or SP6 genes. These across species similarities in function indicate that these two transcription factors may reside in the same developmental pathway. In this paper, we test whether they work in a coordinated manner to exert their effect during amelogenesis. Methods: Two different dental epithelial cell lines, the mouse LS8 and the rat G5 were used for either overexpression or silencing of Msx2 or Sp6 or both. Msx2 mutant mouse embryos or pups were used for in vivo studies. In situ hybridization, semi-quantitative and quantitative real time PCR were employed to study gene expression pattern. MatInspector was used to identify several potential putative Msx2 binding sites upstream of the murine Sp6 promoter region. Chromatin Immunoprecipitation (chIP) was used to confirm the binding of Msx2 to Sp6 promoter at the putative sites. Results: Using the above methods we identified that (i) Msx2 and Sp6 exhibit overlapping expression in secretory ameloblasts, (ii) Sp6 expression is reduced in the Msx2 mouse mutant secretoty ameloblasts, and (iii) that Msx2, like Sp6 inhibits follistatin expression. Specifically, our loss-of function studies by silencing Msx2 and/or Sp6 in mouse dental epithelial (LS8) cells showed significant downregulation of Sp6 but upregulation of Fst expression. Transient transfection of Msx2 overexpression plasmid, up-regulated Sp6 and downregulated Fst expression. Additionally, using MatInspector, we identified several potential putative Msx2 binding sites, 3.5 kb upstream of the murine Sp6 promoter region. By chIP, we confirmed the binding of Msx2 to Sp6 promoter at these sites, thus suggesting that Sp6 is a direct target of Msx2. Conclusion: Collectively, these results show that Sp6 and Msx2 work in a concerted manner to form part of a network of transcription factors that operate during later stages of tooth development controlling ameloblast life cycle and amelogenesis

Soluble matrix from osteoblastic cells induces mineralization by dental pulp cells

Dental pulp cells have a capacity to differentiate into mineralization-inducing cells. To clarify the molecular mechanism, we established an in vitro mineralization-inducing system by rat clonal dental pulp cell line, RPC-C2A, and tried to purify a mineralizationinducing factor in conditioned medium (CM) from preosteoblastic MC3T3-E1 cells. The active factor was impermeable to an ultrafiltrating membrane, and sedimented by ultracentrifugation. The sedimented factor was found as a needle-like structure about 1.3 μm in average length as observed by transmission electron microscopy. The factor contained type I collagen, suggesting not a matrix vesicle, but a soluble matrix. The mineralizationinducing activity was also detected in CM from primary culture of rat calvaria (RC) cells. These results suggested that the soluble matrices from osteoblastic cells serve, at least in part, as differentiation-inducing agents

PERAN PROPOLIS TERHADAP TERJADINYA KARIES GIGI

Penelitian ini bertujuan untuk mengetahui peran propolis terhadap terjadinya karies gigi. Propolis berguna sebagai antibaktori dan dapat mengliambat aktivitas enzim glucosyltransferase. Dua puluh ekor tikus wistar jantan disapih pada umur 30 hari dan dibagi dalam 2 kelompok. Masing masing kelompok terdiri dari 10 ekor tikus. Kelompok pertama diberi air minum, yang mengandung propolls. Kelompok kedua diberi air minum yang tidak mengandung propolis. Semua tikus diberi diet kariogenik yang sama, dan diberi minum. ad libitum selama 32 hari. Setelah 32 hari tikus dianastesi dengan eter dan dikorbankan dengan dekapitasi. Mandibula dipotong dan direndam dalam buffer formalin 10% selama 3 hari, kemudian dicuci dalam air mengalir, kemudian dilakukan pengamatan dengan bantuan kaca, pembesar pada, kesepuluh fissure dari kedua molar bawah (kiri dan kanan, MI dan M2) dan dihitung sebagai karies jika terdapat lesi karies. Analisis hasil menunjukkan terdapat perbedaan yang bermakna antara kelompok tikus yang diberi propolis dan tanpa, propolis (P<0,05)

The effect of 1,25-dihydroxyvitamin D3 on MSX2 gene expression during tooth and alveolar bone development

Background: 1,25-dihydroxyvitamin D3 has been proven to be able to control the formation and biomineralization of tissue through a regulatory gene. A previous research even showed that a cell responsible for the formation of the enamel (ameloblasts), dentin (odontoblasts) and bone (osteoblasts, osteoclasts) was the target of  1,25-dihydroxivitamin D3. Purpose: This research was aimed to determine the role of 1,25- dihydroxyvitamin D3 in vivo in the development of teeth and alveolar bone tissue by analyzing MSX2 gene expression as a gene marker responsible for the growth and development of enamel, dentin, tooth root and alveolar bone. Methods: Samples used for RT-PCR analysis were total RNA of insisivus teeth and alveolar bone derived from mice. RT-PCR analysis was conducted by using primer-specific gene, MSX2. Primer gene, GAPDH, was also used as an internal control. Five hundred nanograms of total RNA were used as a template for PCR. Semi quantitative results of PCR were quantified by using ImageJ software. Results: RT-PCR analysis showed that the expression level of MSX2 was enhanced in the samples of teeth and alveolar bone treated with 1,25 dihydroxyvitamin D3. The increasing of MSX2 expression significantly occurred in alveolar bone samples. Conclusion: It can be concluded that 1,25 dihydroxyvitamin D3 could enhance MSX2 expression as a marker of the development of teeth and alveolar bone tissue. Therefore, 1,25-D3 dihydroxyvitamin is expected to be used as an agent to help the regeneration of teeth and bone tissue.</p