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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
91

Oral Lichenoid Lesions: Differences in expression of TLR4 and TLR9 in Oral Lichen Planus and amalgam induced Oral Lichenoid Lesions

Brecheisen, Mariken, Persson, Julia January 2014 (has links)
Oral lichen planus (OLP) är en idiopatisk kronisk inflammatorisk sjukdom som drabbar munslemhinnan hos ca 2 % av den svenska befolkningen. Amalgamfyllningar kan framkalla lichenoida kontaktlesioner (cOLL), som kliniskt kan vara svåra att särskilja från OLP. Det är dessutom inte möjligt att skilja mellan OLP och cOLL histologiskt. Det är viktigt att kunna särskilja OLP och cOLL då behandlingen av dem skiljer sig.Toll-like receptorer (TLR) finns på flera av kroppens celler. De är en del av det medfödda immunförsvaret men de har också kopplats till autoimmuna sjuksomar. En ökad förekomst av TLR i skivepitel har påvisats vid OLP.Syftet med denna studie är att undersöka variationer i uttrycket av TLR4 och TLR9 i OLP och cOLL. Vår hypotes är att en histologisk skillnad i OLP och cOLL ska kunna observeras p.g.a. skillnader i patogenesen mellan OLP och cOLL.Metod: Vävnadsprov med histologiskt verifierad lichenoid reaktion valdes från Biobanken, Oral Patologi, Malmö från patienter med de kliniskt ställda diagnoserna OLP (10) och cOLL (12). TLR4 och TLR9 identifierades med hjälp av immunhistokemisk färgning varefter reaktionens lokalisation och intensitet jämfördes mellan de två grupperna.Resultat: En signifikant skillnad observerades i infärgningen av TLR4 hos fibroblaster, lymfocyter och makrofager, där TLR4 var mer positiv i cOLL. Uttrycket av TLR9 hos lymfocyter var starkare vid OLP än cOLL.Slutsats: Våra resultat visade att det finns en skillnad i uttrycket av TLR4 och TLR9 i cOLL och OLP. Resultaten bekräftar att OLP och cOLL har olika patogenes, men ytterligare studier behövs för att klargöra hur. / Oral lichen planus (OLP) is an idiopathic chronic inflammatory disease that affects the oral mucosa in approximately 2% of the Swedish population. Amalgam fillings may induce contact oral lichenoid lesions (cOLL) that can be difficult to clinically distinguish from OLP. It is not possible to histologically distinguish between OLP and cOLL. As their treatments differ, the correct diagnosis is vital.Toll-like receptors (TLR) are expressed by most of the body's cells and are part of the innate immune system, however they have also been linked to certain autoimmune diseases. OLP exhibits an increased amount of TLR in the epithelium.The purpose of this study is to investigate the variations in the expression of TLR4 and TLR9 in OLP and cOLL. Our hypothesis is that a histological difference in OLP and cOLL can be observed due to TLRs different roles in maintaining the immune response.Method: Tissue samples with histologically confirmed lichenoid reactions were chosen from Biobank, Oral Pathology, Malmö, from patients with the clinical diagnosis OLP (10 subjects) and cOLL (12 subjects). TLR4 and TLR9 were identified by immunohistochemical staining and compared between the two groups.Results: A significant difference was observed in TLR4 staining of fibroblasts, lymphocytes and macrophages where the antibody was less expressive in OLP. In TLR9 staining lymphocytes were stronger expressed in OLP compared to cOLL.Conclusion: Our results showed that there was a difference in the expression of TLR4 and TLR9 in cOLL and OLP, this could be a result of OLP being an autoimmune disorder. Further studies on this subject are recommended on this subject.
92

Oral Lichenoid Lesions - Differences in expression of TLR4 and TLR9 in Oral Lichen Planus and amalgam induced Oral Lichenoid Lesions

Persson, Julia, Brecheisen, Mariken January 2014 (has links)
Oral lichen planus (OLP) är en idiopatisk kronisk inflammatorisk sjukdom som drabbar munslemhinnan hos ca 2 % av den svenska befolkningen. Amalgamfyllningar kan framkalla lichenoida kontaktlesioner (cOLL), som kliniskt kan vara svåra att särskilja från OLP. Det är dessutom inte möjligt att skilja mellan OLP och cOLL histologiskt. Det är viktigt att kunna särskilja OLP och cOLL då behandlingen av dem skiljer sig.Toll-like receptorer (TLR) finns på flera av kroppens celler. De är en del av det medfödda immunförsvaret men de har också kopplats till autoimmuna sjuksomar. En ökad förekomst av TLR i skivepitel har påvisats vid OLP.Syftet med denna studie är att undersöka variationer i uttrycket av TLR4 och TLR9 i OLP och cOLL. Vår hypotes är att en histologisk skillnad i OLP och cOLL ska kunna observeras p.g.a. skillnader i patogenesen mellan OLP och cOLL.Metod: Vävnadsprov med histologiskt verifierad lichenoid reaktion valdes från Biobanken, Oral Patologi, Malmö från patienter med de kliniskt ställda diagnoserna OLP (10) och cOLL (12). TLR4 och TLR9 identifierades med hjälp av immunhistokemisk färgning varefter reaktionens lokalisation och intensitet jämfördes mellan de två grupperna.Resultat: En signifikant skillnad observerades i infärgningen av TLR4 hos fibroblaster, lymfocyter och makrofager, där TLR4 var mer positiv i cOLL. Uttrycket av TLR9 hos lymfocyter var starkare vid OLP än cOLL.Slutsats: Våra resultat visade att det finns en skillnad i uttrycket av TLR4 och TLR9 i cOLL och OLP. Resultaten bekräftar att OLP och cOLL har olika patogenes, men ytterligare studier behövs för att klargöra hur. / Oral lichen planus (OLP) is an idiopathic chronic inflammatory disease that affects the oral mucosa in approximately 2% of the Swedish population. Amalgam fillings may induce contact oral lichenoid lesions (cOLL) that can be difficult to clinically distinguish from OLP. It is not possible to histologically distinguish between OLP and cOLL. As their treatments differ, the correct diagnosis is vital.Toll-like receptors (TLR) are expressed by most of the body's cells and are part of the innate immune system, however they have also been linked to certain autoimmune diseases. OLP exhibits an increased amount of TLR in the epithelium.The purpose of this study is to investigate the variations in the expression of TLR4 and TLR9 in OLP and cOLL. Our hypothesis is that a histological difference in OLP and cOLL can be observed due to TLRs different roles in maintaining the immune response.Method: Tissue samples with histologically confirmed lichenoid reactions were chosen from Biobank, Oral Pathology, Malmö, from patients with the clinical diagnosis OLP (10 subjects) and cOLL (12 subjects). TLR4 and TLR9 were identified by immunohistochemical staining and compared between the two groups.Results: A significant difference was observed in TLR4 staining of fibroblasts, lymphocytes and macrophages where the antibody was less expressive in OLP. In TLR9 staining lymphocytes were stronger expressed in OLP compared to cOLL.Conclusion: Our results showed that there was a difference in the expression of TLR4 and TLR9 in cOLL and OLP, this could be a result of OLP being an autoimmune disorder. Further studies on this subject are recommended on this subject. MeSH: "Dental Amalgam", "Dermatitis, Allergic Contact", "Immunohistochemistry", "Lichen Planus, Oral", "Toll-Like Receptor 4", "Toll-Like Receptor 9"
93

Anticariogenic in situ effect of different restorative dental materials / AvaliaÃÃo in situ do efeito anticariogÃnico de diferentes materiais restauradores

Rosane Pontes de Sousa 24 April 2008 (has links)
Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / Tooth structure immediately adjacent to restorations is susceptible to secondary caries, which may be caused by imperfect adaptation of restorative materials and subsequent microorganism colonization. Therefore, in order to identify methods of preventing secondary caries and increasing clinical dental restoration durability, different restorative dental materials have been introduced and applied in dental clinics. Thus, this in situ study assessed the effects of different restorative materials on the microbiological composition of dental biofilm and evaluated their ability of protecting the adjacent enamel against acid attacks from bacterial activity. A double-blind, split-mouth design was performed in one phase of 14 days, during which, 20 volunteers wore intra-oral palatal devices with five human enamel slabs, which were extra-orally restored according to the manufacturerâs specifications, using one of the following materials: Filtek Z 250/Single Bond composite resin; Permite amalgam; Fuji II encapsulated resin-modified glass ionomer; Vitremer resin-modified glass ionomer and Ketac Molar conventional glass ionomer.. During the experimental period, all subjects used fluoride-containing dentifrice 3x/day and a 20% sucrose solution was dripped onto the slabs 8x/day in predetermined times. The biofilm formed on the slabs was analyzed to determine total and mutans streptococci as well as lactobacilli counts. Demineralization (delta S) was determined on enamel by cross-sectional microhardness at 20 and 70 -Âm from the restoration margin. In order to verify the differences among the treatments, Kruskal-Wallis and ANOVA followed by Minimum Squares test were applied for cariogenic microbiota and delta S, respectivly. No statistically significant differences were found in the cariogenic microbiota grown on the slabs. At 20-Âm distance, only Fuji II statistically differed from the other groups presenting the lowest demineralization. At 70-Âm, Fuji II significantly inhibited demineralization when compared to Permite, Filtek-Z-250 and Ketac Molar. Concluding, in the background of fluoride dentifrice and under the cariogenic exposure condition of this study, only the encapsulated resin-modified glass ionomer material provided additional protection against secondary caries. / A estrutura dentÃria imediatamente adjacente a restauraÃÃes à suscetÃvel ao surgimento de cÃrie secundÃria, que pode ocorrer devido a imperfeiÃÃes na adaptaÃÃo de materiais restauradores e subseqÃente colonizaÃÃo por microrganismos. Logo, com o objetivo de identificar os mÃtodos de prevenÃÃo da cÃrie secundÃria e aumentar a longevidade das restauraÃÃes, diferentes materiais restauradores tÃm sido introduzidos e usados na clÃnica odontolÃgica. Desta forma, este estudo in situ avaliou os efeitos de diferentes materiais restauradores na composiÃÃo microbiolÃgica do biofilme dental bem como a habilidade destes materiais em proteger o esmalte adjacente dos ataques Ãcidos provenientes da atividade bacteriana. Foi empregado um delineamento duplo-cego, âsplit-mouthâ realizado em uma fase de 14 dias, durante a qual, 20 voluntÃrios utilizaram dispositivos intra-orais palatinos com cinco blocos de esmalte dental humano que foram restaurados extra-oralmente, de acordo com as recomendaÃÃes do fabricante com um dos seguintes materiais: Resina composta Filtek Z250/Single Bond (grupo controle), AmÃlgama Permite, IonÃmero de vidro modificado por resina encapsulado Fuji II, IonÃmero de vidro modificado por resina Vitremer e IonÃmero de vidro convencional Ketac Molar. Durante o perÃodo experimental, os voluntÃrios utilizaram dentifrÃcio fluoretado, 3 vezes ao dia e gotejaram sobre os blocos, uma soluÃÃo de sacarose a 20%, 8 vezes ao dia em horÃrios prÃ-determinados. No 14o dia, o biofilme formado sobre os blocos foi removido para determinar a contagem de estreptococos totais e estreptococos mutans, bem como lactobacilos. A desmineralizaÃÃo (delta S) ao redor da restauraÃÃo foi avaliada atravÃs da anÃlise de microdureza em corte longitudinal do esmalte a 20 e 70 Âm da margem da restauraÃÃo. Para detectar as diferenÃas entre os tratamentos, foram aplicados os testes Kruskal-Wallis e ANOVA seguida do teste dos quadrados mÃnimos para a microbiota cariogÃnica e delta S, respectivamente. NÃo foram encontradas diferenÃas estatisticamente significativas na microbiota cariogÃnica formada sobre os blocos. Na distÃncia 20 Âm, somente o Fuji II diferiu estatisticamente dos outros grupos apresentando a menor desmineralizaÃÃo. A 70 Âm, o Fuji II inibiu significativamente a desmineralizaÃÃo quando comparado ao Permite, Filtek-Z-250 e Ketac Molar. Conclui-se que na situaÃÃo de uso de dentÃfricio flouretado associada ao desafio cariogÃnico do presente estudo, somente, o ionÃmero de vidro modificado por resina encapsulado apresentou uma proteÃÃo adicional contra o desenvolvimento de cÃrie secundÃria
94

Biokompatibilnost i marginalna adaptacija mineral-trioksid agregata, trikalcijum-silikatnog cementa i amalgama kao materijala za retrogradno zatvaranje kanala korena zuba / Biocompatibility and marginal adaptation of mineral trioxide aggregate, tricalcium silicate cement and dental amalgam as a root end filling materials

Jovanović Lena 25 October 2019 (has links)
<p>Već izvesno vreme u stručnoj literaturi vodi se rasprava o biokompatibilnosti materijala koji se koriste u periapikalnoj hirurgiji. Pored biokompatibilnosti, od materijala za retrogradnu opturaciju kanala korena zuba se očekuje da spreči prodor bakterija iz kanalnog sistema u okolna tkiva. Kvalitetno rubno zaptivanje, odnosno adekvatna marginalna adaptacija su među najznačajnijim faktorima za dugoročan uspeh tretmana. Cilj ovog istraživanja je bio ispitati biokompatibilnost i utvrditi da li postoji razlika u biokompatibilnosti između mineral-trioksid agregata, trikalcijum-silikatnog cementa i amalgama na osnovu tri standadna testa citotoksičnosti, kao i utvrditi marginalnu adaptaciju ispitivanih materijala za retrogradno zatvaranje kanala korena zuba. Materijali i metode: Eksperimentalni deo istraživanja je podeljen na dva dela. U prvom delu istraživanja je vr&scaron;eno ispitivanje biokompatibilnosti materijala, dok je u drugom delu vr&scaron;eno ispitivanje marginalne adaptacije na osnovu mikrofotografija dobijenih skening elektronskim mikroskopom. Ispitivanje biokompatibilnosti je izvr&scaron;eno na dve ćelijske linije, liniji mi&scaron;jih fibroblasta (L929) i liniji humanih fibroblasta (MRC-5). U eksperimentima su kori&scaron;ćene samo žive (vijabilne) ćelije. Broj ćelija i njihova vijabilnost je određena testom odbacivanja boje sa 0,1% tripan plavim. Vijabilnost ćelija kori&scaron;ćenih u eksperimentu je bila veća od 90%. Biokompatibilnost sve tri vrste materijala je ispitana na osnovu standardnih testova biokompatibilnosti: DET test, MTT test, Agar difuzioni test. Ispitivanje marginalne adaptacije je sprovedeno na 90 ekstrahovanih jednokorenih zuba interkaninog sektora gornje vilice sa intaktnom pulpom, zavr&scaron;enim rastom korena, bez frakture i resorpcije korena zuba. Izvr&scaron;ena je endodontska obrada svih zuba i nakon toga su zubi ostavljeni u vlažnoj sredini na 48h, da bi se sprečile frakture prilikom sečenja. Nakon mehaničko medikamentozne obrade i opturacije kanala korena zuba je vr&scaron;ena resekcija vrha korena zuba 3mm, a nakon toga su svi zubi preparisani do dubine od 3 mm unutar kanala, ultrazvučnim nastavcima (EMS, miniMaster Piezon scaler). Zubi su naizmenično podeljeni u 3 grupe (30 zuba po grupi). Prvu grupu čine zubi kojima je apikalni kavitet biti ispunjen amalgamom, u drugoj grupi, apikalni kavitet je ispunjen MTA, a u trećoj trikalcijum-silikatnim cementom. Nakon retrogradne opturacije, zubi su ostavljeni u vlažnoj sredini 48h, do potpunog vezivanja ispitivanih materijala. Nakon vezivanja ispitivanih materijala, zubi su sečeni longitudinalno, finom dijamantskom &scaron;ajbnom. Marginalna adaptacija ispitivanih materijala je procenjena skening elektronskim mikroskopom (SEM). Pripremljeni uzorci su posmatrani pod uvećanjima 30x, 40x, 80x i 100x. Uvećanje 30x je rađeno radi prikaza celokoupnog retrogradnog punjenja na jednom snimku, tj. spoja materijal-zub. Nakon toga je napravljeno vi&scaron;e uzastopnih snimaka sauvećanjem 80x do pune dužine materijala. Na taj način je utvrđeno postojanje i izvr&scaron;eno merenje marginalne pukotine u mikrometrima. Merenja ukupne dužine marginalne pukotine u mikrometrima u 5 tačaka sa obe strane preparata su vr&scaron;ena u softverskoj aplikaciji Image J software (National Institutes of Health, Bethesda, USA). Tačke su izabrane tako da tačka 1a i tačka 5a predstavljaju gornju i donju ivicu preparata. Tačka 3a predstavlja sredinu rastojanja između tačke 1a i tačke 5a. Tačka 2a i tačka 4a predstavljaju sredinu razmaka između tačke 1a i 3a, odnosno 3a i a5. Tačke 1b-5b su naspramne tačke. Rezultati biokompatibilnosti ukazuju na visok stepen ćelijske kompatibilnosti svih ispitivanih materijala. Međutim, DET testomnije utvrđena statistički značajna razlika u citotoksičnosti između istovetnih ispitivanih materijala u obe ćelijske linije, niti između sva tri ispitivana materijala u obe ćelijske kulture.Poređenjem rezultata MTT testa nakon 24h i 48h, kao i nakon 48h i 72h uočava se da su dobijene srednje vrednosti indeksa citotoksičnosti kod sva tri ispitivana materijala i na obe ćelijske linije manje nakon 48h, odnosno nakon 72h, &scaron;to ukazuje na oporavak ćelijskog metabolizma. Poređenjem rezultata nakon 24h i nakon 72h, uočava se znatno veći pad vrednosti indeksa citotoksičnosti nakon 72h kod sva tri ispitivana materijala i na obe ćelijske linije. U kulturi ćelija MRC5, kod sva tri ispitivana materijala postoji statistički značajna razlika između indeksa citotoksičnosti izmerenog nakon 24h i nakon 72h, kao i u kulturi ćelija L929. Agar difuzionim testom nije uočena dekolorizacija, niti liza ćelija ispod ispitivanih materijala. Ćelijski odgovor je 0/0 &scaron;to ukazuje da ovim testom nije utvrđeno postojanje citotoksičnog efekta ispitivanih materijala na ćelijske linije L929 i MRC-5. Ispitivanje marginalne adaptacije materijala je vr&scaron;eno na osnovu mikrofotografija dobijenih skening elektronskim mikroskopom.. Najpre su testirane razlike na prvoj tački merenja. Rezultati ovog testa pokazuju da postoje značajne razlike između materijala i da amalgam ima značajno vi&scaron;e vrednosti izmerenih pukotina u odnosu na preostala dva materijala, dok se vrednosti za MTA i biodentin međusobno značajno ne razlikuju. Kao jo&scaron; jedna referentna tačka uzeta je tačka merenja 5. I u odnosu na vrednosti u ovoj tački merenja zabeležene su značajne razlike između materijala. Post hoc Mann-Whitney test pokazuje da se amalgam značajno razlikuje od preostala dva materijala, dok nema značajnih razlika između MTA i biodentina. Na osnovu medijane može se videti da amalgam ima niže vrednosi u ovoj tački merenja u odnosu na preostala dva materijala. U tačkama 2-4, kao i u tačkama 1-5 (ukupno), ne postoji statistički značajna razlika u marginalnoj adaptaciji ispitivanih materijala. Rezultati biokompatibilnosti ukazuju na visok stepen ćelijske kompatibilnosti svih ispitivanih materijala. Rezultati sva tri testa pokazuju da ne postoji statistički značajna razlika u citotoksičnosti između ispitivanih materijala. MTT test pokazuje da u obe ćelijske kulture, kod istovetnih ispitivanih materijala postoji statistički značajna razlika između indeksa citotoksičnosti izmerenog nakon 24h i nakon 72h. Rezultati ispitivanja marginalne adaptacije pokazuju da u tački 1 najgore zaptiva amalgam, dok izmedju MTA i biodentina nema razlike. U tački 5 najbolje zaptiva amalgam.</p> / <p>Biocompatibility of materials, deployed in periapical surgery, has been a subject of debate in referential literature for some time now. Apart from biocompabillity, root end filling materials are expected to prevent bacteria from entering the surrounding tissue from canal system. The most important factors for successful long term treatment include marginal seal, i.e. adequate marginal adaptation. The aim of this research was to examine biocompatibility and establish the potential difference in biocompatibility between mineral trioxide aggregate, tricalcium silicate cement and dental amalgam according to three cytotoxicity tests, but also to corroborate marginal adaptation of the materials in question for retrograde seal of a root canal. Materials and methods: The experimental part of the research is divided in two parts. In the first part of the research biocompatibility of the materials was examined, while the examination of the marginal adaptation based on the micro images from scanning electron microscope was conducted in the second part. The examination of biocompatibility was executed on two cell lines, mouse fibroblast cell line (L929) and human cell line (MRC-5).Biocompatibility of all three types of material was examined based on three standard biocompatibility tests: DET test, MTT test, Agar diffusion test.The examination of marginal adaptation was carried out on 90 single-rooted tooth extractied human teeth of the intercanine sector of maxilla with intact pulp, mature apices, without root fractures or resorption. All teeth were endodontically treated. After the extirpation, irrigation and opturation, the resection of 3mm of root apex and retrograde preparation with ultrasonic instruments up to 3 mm depth inside the canal was done. Teeth were divided in three groups alternately. The First group include teeth which apical cavitation was filled with amalgam, in the Second group apical cavitation was filled with MTA, and in the Third group with tricalcium silicate cement. After the complete setting of the materials, teeth were cut in longitudinal manner, with fine, diamond tool. Marginal adaptation of the materials was assessed through scanning electron microscope (SEM). Software application Image J software was deployed to measure the total length of marginal fissure in micrometers in 5 pointson both sides of the preparation . The results of biocompatibility indicate high degree of cell compatibility of all tested materials. DET test did not assert any statistically significant difference in cytotoxicity between the same tested materials in both cell lines, nor between all three tested materials in both cell cultures. Comparing the results of MTT test after 24h and 48h, and 48h and 72h, it is noted that middle value of cytotoxicity index with all three tested materials and on both cell lines is lower after 48h, and after 72h, indicating the recovery of cell metabolism. In both cell cultures, with all three tested materials there is statistically significant difference between measured cytotoxicity indices after 24h and after 72h. Agar diffusion test did not show decolorization, nor cell lysis underneath the tested materials, which means that cytotoxic effect was not asserted on cell lines L929 i MRC-5. The examination of marginal adaptation was conducted according to micro images gained by scanning electron microscope. The results in the measure point 1 indicate there are significant differences between materials, and amalgam has significantly higher values of the measured fissures in relation to remaining two materials, whereas values for MTA and biodentine do not differ significantly. In measure point 5 significant differences were noted. Post hoc Mann-Whitney test shows that amalgam has lower values of the tested fissures in this measure point in relation to two other materials, while there were no significant differences between MTA i biodentine. In points 2-4, as well as points 1-5 (in total), there were no statistically significant differences in marginal adaptation of the examined materials. The results of all three tests show that there is no statistically significant difference in cytotoxicity between examined materials. MTT test shows that there is, in both cell cultures, with the same examined materials , statistically significant difference between cytotoxicity indices measured after 24h and after 72h. The results of the examination of marginal adaptation show that in point 1 amalgam has the worst seal, whereas between MTA and biodentine there is no difference. In point 5 amalgam has the best seal.</p>

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