Diss. Stockholm : Karol. inst.

Thesis (M.S.)--University of Michigan, 1975.

Thesis (M.S.)--University of Michigan, 1975.

Thesis (M.S.)--University of Alabama at Birmingham, 2009. / Title from PDF title page (viewed on Sept. 3, 2009). Includes bibliographical references (p. 32-37).

Orientadores: Mirela Sanae Shinohara, Mário Fernando de Góes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-21T23:51:52Z (GMT). No. of bitstreams: 1 Freitas_MarcelaSantiago_M.pdf: 38797129 bytes, checksum: 16869befa66eba198d1cb13ad5c9ac1d (MD5) Previous issue date: 2013 / Resumo: Estudos mostram que a resistência de união (RU) alcançada pelos sistemas adesivos autocondicionantes em superfície de esmalte pré-condicionado é significativamente maior se comparada aos valores obtidos em esmalte não condicionado. A partir destas evidências, este estudo teve como objetivo avaliar a RU e a morfologia da interface adesiva (MI) em esmalte e dentina de um adesivo autocondicionante de passo único multi-mode e um adesivo autocondicionante de dois passos com e sem pré-condicionamento ácido da superfície comparado a dois sistemas adesivos de condicionamento total, de dois e três passos. Terceiros molares humanos recém-extraídos foram seccionados para obtenção de superfícies planas em esmalte e dentina, as quais foram desgastadas com lixa SiC #600 para padronização da smear layer. Estas amostras foram divididas aleatoriamente em 6 grupos: (SBU) Scotchbond Universal; (SBUcond) SBU précondicionado; (CSE) Clearfil SE Bond; (CSEcond) CSE pré-condicionado; (SBMP) Scotchbond Multi-Purpose; e (EX) Excite F. Os grupos de condicionamento total e os autocondicionantes a serem avaliados com pré-condicionamento receberam a aplicação do ácido fosfórico por 15s em dentina e 30s em esmalte. Todos os sistemas adesivos foram aplicados de acordo com as recomendações dos fabricantes. Em seguida, um bloco de resina composta (Filtek Supreme Plus) foi construído incrementalmente sobre cada superfície preparada para o teste de RU, e para a MI, as superfícies foram restauradas com resina flow (Filtek Z-350 Flowable Restorative) formando um "sanduíche", de esmalte ou dentina. Após 24h, para avaliação da RU, as amostras foram seccionadas em palitos com área transversal de 0,8mm2 e submetidos ao teste de microtração com velocidade de 1,0mm/min. Os resultados foram analisados estatisticamente pelos testes one-way ANOVA e Fisher's PLSD (?=0.05) e os padrões de fratura analisados em Microscopia Eletrônica de Varredura (MEV). Para análise da MI, duas amostras de cada grupo foram incluídas em resina epóxica, polidas e observadas em MEV. Para esmalte, os resultados de RU mostraram que o SBUcond e CSEcond obtiveram os maiores valores, seguidos dos grupos SBMP, SBU e CSE que não apresentaram diferenças entre si. O grupo EX obteve os menores valores comparados aos outros grupos. Na análise da MI, os grupos SBUcond e CSEcond apresentaram nítidas extensões do adesivo penetrado no esmalte desmineralizado, semelhante aos sistemas de condicionamento total. Já para dentina, os resultados de RU mostraram que o condicionamento ácido prévio diminuiu significativamente os valores de RU dos sistemas autocondicionantes. Os maiores valores foram obtidos pelo SBU, CSE e SBMP, com valores de RU estatisticamente equivalentes entre si. Como em esmalte, o sistema adesivo EX obteve os menores valores. A análise em MEV da MI mostrou que o condicionamento prévio da dentina com adesivos autocondicionantes forma uma camada híbrida mais espessa com formação de tags resinosos, semelhantes aos sistemas adesivos de condicionamento total. Pode-se concluir que em esmalte, o condicionamento prévio aumentou significativamente os valores de RU para os sistemas autocondicionantes. Contudo, estes sistemas adesivos não apresentaram diferença estatística do adesivo convencional SBMP. E para dentina, o pré-condicionamento dos adesivos autocondicionantes diminuiu significativamente os valores de RU, entretanto, os valores de SBUcond não foram diferentes significativamente dos obtidos pelo sistema adesivo convencional SBMP / Abstract: Studies show that the bond strength (BS) achieved by self-etching adhesive systems on pre-etched enamel surface is significantly higher compared with the values obtained on unetched enamel. From this evidence, this study aimed to assess the BS and morphology of the adhesive interface (AI) on enamel and dentin of a one-step self-etching adhesive multi-mode and a two-step selfetching adhesive with and without pre-etching of surface compared with two totaletching adhesive systems, two and three steps. Recently extracted human third molars were sectioned to obtain flat surfaces in enamel and dentin, which were ground with #600 SiC sandpaper to standardize the smear layer. These samples were randomly assigned into 6 groups: (SBU) Scotchbond Universal; (SBU-et) SBU pre-etched; (CSE), Clearfil SE Bond, (CSE-et) CSE pre-etched; (SBMP) Scotchbond Multi-Purpose, and (EX) Excite F. The groups total-etching and selfetching to be evaluated with pre-etching received the application of phosphoric acid for 15s in dentin and 30s in enamel. All adhesive systems were applied according to manufacturers' recommendations. Then, a block of composite resin (Filtek Supreme Plus) was constructed incrementally on each surface prepared for BS testing. For AI, the areas were filled with flowable resin (Filtek Flowable Restorative Z-350) forming a "sandwich" of enamel or dentin. After 24 hours, to review the BS, the specimens were sectioned into sticks with cross-sectional area of 0.8mm² and submitted to microtensile test at a speed of 1.0mm/min. The results were statistically analyzed by one-way ANOVA test and Fisher's PLSD (?=0.05) and fracture patterns were analyzed through Scanning Electron Microscopy (SEM). For analysis of AI, two samples from each group were embedded in epoxy resin, polished and observed through SEM. For enamel, the results of BS showed that SBU-et and CSE-et obtained the highest values, followed by SBMP groups, SBU and CSE with no differences among them. The EX group obtained the lowest values of all other groups. In the analysis of AI, and CSE-et and SBU-et groups showed sharp tag extensions of the adhesive penetrated in the demineralized enamel, similar to total-etching systems. As for dentin, BS results showed that acid etching significantly reduced the BS values of self-etching systems. The highest values were obtained by the SBU, CSE and SBMP with BS values statistically equivalent to each other. As in enamel, the adhesive system EX obtained the lowest values. SEM analysis showed that BS for pre-etched dentin with selfetching adhesive forms a thicker hybrid layer with resin tags formation, similar to total-etching adhesive systems. It can be concluded that on enamel, the preetching significantly increased BS for self-etching systems. However, these adhesive systems showed no statistical difference from conventional adhesive SBMP. And to dentin, pre-etching of sel-etching adhesives significantly reduced BS, however, SBU-et values were not significantly different from those obtained by the conventional adhesive system SBMP / Mestrado / Dentística / Mestra em Materiais Dentários

Orientador: Luís Alexandre Maffei Sartini Paulillo / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-24T07:41:05Z (GMT). No. of bitstreams: 1 Coppini_ErickKamiya_M.pdf: 3349153 bytes, checksum: e0323d6512c30cee2e8ea17128a4c6e6 (MD5) Previous issue date: 2013 / Resumo: The aim of this study was to evaluate the cavosuperficial enamel acid-etching influence in class I cavities, filled with composites on microtensile bond strength, Knoop microhardness and nanoleakage after thermomechanic ageing. It was selected 76 sound molar splitted on: 32 teeth to microtensile test (n=8); 32 teeth to Knoop microhardness (n=8); and 12 teeth (n=3) to nanoleakage analysis. The cavities were prepared on a standard cavity preparation machine. Half of the teeth had the cavosuperficial enamel etched with 35% phosphoric acid and restored with a Silorane restorative system or a Methacrylate restorative system. After the conclusion of the restoration procedures, the teeth were taken to a thermomechanic cycling machine where the artificial ageing was performed with 200.000 mechanical cycles with an 80 N load in a 2HZ frequency and thermocycling by filling the chambers for 30 seconds and 15 seconds drainage with the temperatures varying between 5ºC and 55ºC. The samples were submitted to the microtensile bond strength test, Knoop microhardness and nanoleakage evaluation. To statistical analysis it was performed the ANOVA two-way and Tuckey test (p ? 0,05). The group restored with methacrylate without acid-etching showed the lowest values of microtensile bond strength and it was statistically different to the other groups that have no difference between them. The methacrylate composite presented statistically higher values on Knoop microhardness compared to silorane composite. The nanoleakage analysis showed low infiltration to silorane restorative system and moderate infiltration to the methacrylate restorative system. The methacrylate group restored without enamel acid-etching showed the formation of Water Trees. It can be concluded that the acid-etching improved the bond strength to the methacylate system. The methacrylate composite has bigger Knoop microhardness than silorane composite. The methacrylate restorative system showed moderate infiltration on nanoleakage analysis / Abstract: The aim of this study was to evaluate the cavosuperficial enamel acid-etching influence in class I cavities, filled with composites on microtensile bond strength, Knoop microhardness and nanoleakage after thermomechanic ageing. It was selected 76 sound molar splitted on: 32 teeth to microtensile test (n=8); 32 teeth to Knoop microhardness (n=8); and 12 teeth (n=3) to nanoleakage analysis. The cavities were prepared on a standard cavity preparation machine. Half of the teeth had the cavosuperficial enamel etched with 35% phosphoric acid and restored with a Silorane restorative system or a Methacrylate restorative system. After the conclusion of the restoration procedures, the teeth were taken to a thermomechanic cycling machine where the artificial ageing was performed with 200.000 mechanical cycles with an 80 N load in a 2HZ frequency and thermocycling by filling the chambers for 30 seconds and 15 seconds drainage with the temperatures varying between 5ºC and 55ºC. The samples were submitted to the microtensile bond strength test, Knoop microhardness and nanoleakage evaluation. To statistical analysis it was performed the ANOVA two-way and Tuckey test (p ? 0,05). The group restored with methacrylate without acid-etching showed the lowest values of microtensile bond strength and it was statistically different to the other groups that have no difference between them. The methacrylate composite presented statistically higher values on Knoop microhardness compared to silorane composite. The nanoleakage analysis showed low infiltration to silorane restorative system and moderate infiltration to the methacrylate restorative system. The methacrylate group restored without enamel acid-etching showed the formation of Water Trees. It can be concluded that the acid-etching improved the bond strength to the methacylate system. The methacrylate composite has bigger Knoop microhardness than silorane composite. The methacrylate restorative system showed moderate infiltration on nanoleakage analysis / Mestrado / Dentística / Mestre em Clínica Odontológica

Este estudo in vitro avaliou a influência do clareamento ativado com luz híbrida, em função da variação do pH e concentração de géis clareadores, e do condicionamento ácido prévio do esmalte bovino na alteração da rugosidade e desgaste após escovação simulada. Fragmentos de esmalte (1,5cm x 0,5cm x 0,4cm) foram divididos em duas partes, ficando uma metade como controle e a outra como área teste. Esta última foi subdividida em duas metades, sendo que uma recebeu o condicionamento ácido somado ao gel clareador e a outra somente o gel clareador. Os espécimes foram divididos aleatoriamente em seis grupos (n=10): C = controle; TBO35LH = Total Blanc Office 35% 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPS35LH= Lase Peroxide Sense 35% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPS25LH = Lase Peroxide Sense 25% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPL15LH = Lase Peroxide Lite 15% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPL10LHV = Lase Peroxide Lite 10% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser violeta. A rugosidade aritmética (Ra) inicial, após clareamento e após escovação, foi determinada pela média (μm) de três leituras (em cada área sem e com ácido totalizando seis leituras por espécimes) com o rugosímetro Hommel Tester T 1000. Os valores médios do pH foram determinados pelo peagômetro digital Sentron Model 1001 nos tempos inicial e final. Os espécimes foram armazenados em saliva artificial por sete dias, submetidos a 100.000 ciclos de escovação simulada. Após 24 horas o desgaste superficial foi determinado (μm) empregando o mesmo rugosímetro. Em relação ao desgaste e a alteração de rugosidade superficial, os resultados foram submetidos à Anova a dois critérios e a dois critérios de medidas repetidas e posteriormente ao teste de Tukey. Os dados obtidos das leituras de pH foram submetidos à ANOVA a um critério e a dois critérios de medidas repetidas e ao teste de Kruskal Wallis e Tukey para comparações individuais entre os grupos. Para todos os testes o nível de significância foi de 5%. A rugosidade e o desgaste apontaram diferenças estatísticas entre os grupos, principalmente quando comparado à área com e sem ácido. Os géis clareadores apresentaram tendência de diminuição dos valores de pH do tempo inicial para o tempo final, contudo, uma correlação com a rugosidade e com o desgaste não pôde ser estabelecida de forma clara. / This in vitro study evaluated the influence of whitening activated with hybrid light on the function variations of the pH level and concentration of bleaching gels and prior acid etching of bovine enamel and the change in roughness and wear after simulated tooth brushing. Fragments of enamel (1.5 cm x 0.5 cm x 0.4 cm) were divided into two parts, one half as the control and the other as the test area. The latter was divided into two halves, one of which received the etching added to the whitening gel and the other with only the whitening gel. The specimens were randomly divided into six groups (n = 10): C = control; TBO35LH = 35% Total Blanc Office 1x session (5x8\') + activation with hybrid light LED/Laser; LPS35LH = 35% Lase Peroxide Sense - 1x session (5x8\') + activation with hybrid light LED/Laser; LPS25LH = 25% Sense Lase Peroxide - 1x session (5x8\') + activation with hybrid light LED/Laser; LPL15LH = 15% Lase Peroxide Lite - 1x session (5x8 \') + activation with hybrid light LED/Laser; LPL10LHV = 10% Lase Peroxide Lite - 1x session (5x8\') + activation with violet hybrid light LED/Laser. The arithmetic roughness (Ra) started after bleaching and after brushing was determined by averaging (μm) the three readings (in each area - with and without acid for a total of six readings per specimen) with a Rugosimeter Hommel Tester T 1000. The mean pH values were determined by the Sentron Model 1001 digital pH meter at the start and end times. The specimens were stored in artificial saliva for seven days, and subjected to 100,000 cycles of simulated brushing. After 24 hours, the surface wear was determined (μm) employing the same roughness meter. In relation to the change in wear and surface roughness, the results were evaluated by two way ANOVA testing for repeated measures and later, a Tukey\'s test. The data obtained from the pH readings were submitted to two way ANOVA testing for repeated measures and the Kruskal Wallis and Tukey tests for the comparisons between the individual groups. The significance level was set at 5% for all the tests. The roughness and wear showed statistical differences between the groups, especially when compared to the area with and without acid. The bleaching gels tended to decrease in pH from the starting time to the final time, however, a correlation with the roughness and wear could not be clearly established.

Orientador: Mario Fernando de Goes / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-08T13:06:43Z (GMT). No. of bitstreams: 1 Caiado_AnaCarolinaRochaLima_M.pdf: 12410221 bytes, checksum: 10dff9d1f7b58797480e9a00a97d0a78 (MD5) Previous issue date: 2006 / Resumo: Este estudo teve como objetivos: (a) caracterizar a morfologia, a densidade e a área transversal de túbulos dentinários da dentina coronária (profunda) e radicular (terço cervical) intactas e após condicionamento com ácido fosfórico 32% (AF) e primer condicionante do sistema adesivo Clearfill Protect Bond (P); e (b) avaliar e comparar a resistência de união e os padrões de fratura obtidos na dentina coronária (profunda) e dentina radicular (terço cervical). Pré-molares humanos hígidos foram fixados em gluteraldeído (2,5%). Secções da dentina coronária profunda e dentina radicular (região cervical) foram obtidas por clivagem. Cada dente recebeu os seguintes tratamentos: G1- dentina coronária + AF; G2- dentina coronária + P; G3 - dentina coronária sem tratamento; G4- dentina radicular + AF; G5- dentina radicular + P; G6- dentina radicular sem tratamento. As secções condicionadas com primer foram imersas em etanol e acetona. Todos os grupos foram desidratados em concentrações ascendentes de álcool e HMDS e visualizadas por microscopia eletrÃ'nica de varredura em ampliação de 1500X. As imagens obtidas foram usadas para calcular a densidade (D) e a área (A) da secção transversal dos túbulos dentinários em µm2 utilizando o programa Leica IM50. Para o teste de microtração foram utilizados fatias de dentina coronária profunda e dentina radicular cervical de 12 dentes que foram divididas em quatro grupos de acordo com a região dentinária e o sistema adesivo utilizado: G7- dentina radicular + Single Bond II; G8- dentina radicular + Clearfill Protect Bond; G9- dentina coronária + Single Bond II; G10- dentina coronária + Clearfill Protect Bond. Resina composta foi acrescentada em ambos os lados das fatias. Foram obtidas dessas fatias espécimes em forma de palito. Após armazenamento em água (37ºC) os espécimes foram submetidos ao teste de microtração em uma máquina de ensaio universal (Instron), a uma velocidade de 0,5mm/min. A dentina radicular intacta do terço cervical apresentou uma superfície irregular formada por calcosferitos, o que a difere estruturalmente da dentina coronária. Já a densidade (42.627/mm2) e a área transversal média (2,9035/ µm2) dos túbulos dentinários na raiz não revelou diferença estatisticamente significante (p> 0,05) aos valores encontrados na coroa. Os dados de resistência de união foram estatisticamente superiores na dentina coronária (26.63 MPa) do que na dentina radicular (19.76 MPa). O padrão de fratura mais frequentemente encontrado para ambas as regiões foi a fratura mista (coesiva no adesivo e na camada híbrida). ÿ possível concluir que as dentinas coronária (profunda) e radicular do (terço cervical) apresentam diferenças morfológicas e nos valores de resistência de união, porém apresentam semelhanças quanto à densidade de túbulos e padrões de fratura independente do sistema adesivo utilizado / Abstract: The aim of this study was to: (a) characterize the morphology, density and transversal cross-section area of tubules of deep crown and cervical root dentine, intact and after etched with 32% phosphoric acid (AF) or the self-etch primer of the Clearfill Protect Bond adhesive system (P); and (b) evaluate and compare the bond strength and the fracture patterns obtained from deep crown dentine and cervical root dentine. Human carie-free premolars (n=5) were fixed in 25% glutaraldehyde. Deep crown and root dentine sections were obtained by cleavage. Each tooth was treated as follows: G1- crown dentine + AF; G2- crown dentine and P; G3-intact crown dentine; G4- root dentine + AF; G5- root dentine + P; G6- intact root dentine. The sections etched with primer were immersed in ethanol and acetone. All groups were dehydrated in increasing alcohol concentration and Hexamethyldisilazane, nd were visualized by Scanning Electron Microscopy. A magnification of 1500X was used to calculate the density (D) and the dentinal tubule transversal cross-section area per mm2, using the program Leica IM50. For microtensile testing, twelve premolars were cut to obtain slices of deep crown dentine and cervical root dentine. These were divided in four groups according to dentine region and adhesive system employed: G7- root dentine + Single Bond II; G8- root dentine + Clearfill Protect Bond; G9- crown dentine + Single Bond II; G10- crown dentine + Clearfill Protect Bond. Restorative was added to both sides of the slices. Beam specimens were obtained from these restored slices which were kept in water at 37ºC. The specimens were microtensile tested using a universal testing machine (Instrom) at a speed of 0,5mm/min. Intact cervical root dentine presented an irregular surface formed with calcospherites, demonstrating its structural difference from coronary dentine. On the other hand, root dentine tubule density (42,627/mm2) and average transversal area (2.9035/ µm2) did not reveal statistically significant difference (p>0.05) when compared to values obtain in crown. Bond strength results were statistically superior for crown dentine (26.63 MPa) then root dentine (19.76 MPa). Mixed fractures (cohesive in adhesive and hybrid layer) were the most frequent fracture patterns found for both regions. It is possible to conclude that deep crown dentine and cervical root dentine present morphological and bond strength differences, however, are similar in relation to tubule density and fracture patterns independent of the adhesive system employed. / Mestrado / Endodontia / Mestre em Clínica Odontológica

Este estudo in vitro avaliou a influência do clareamento ativado com luz híbrida, em função da variação do pH e concentração de géis clareadores, e do condicionamento ácido prévio do esmalte bovino na alteração da rugosidade e desgaste após escovação simulada. Fragmentos de esmalte (1,5cm x 0,5cm x 0,4cm) foram divididos em duas partes, ficando uma metade como controle e a outra como área teste. Esta última foi subdividida em duas metades, sendo que uma recebeu o condicionamento ácido somado ao gel clareador e a outra somente o gel clareador. Os espécimes foram divididos aleatoriamente em seis grupos (n=10): C = controle; TBO35LH = Total Blanc Office 35% 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPS35LH= Lase Peroxide Sense 35% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPS25LH = Lase Peroxide Sense 25% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPL15LH = Lase Peroxide Lite 15% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser; LPL10LHV = Lase Peroxide Lite 10% - 1 sessão (5x8) + ativação com luz híbrida LED/Laser violeta. A rugosidade aritmética (Ra) inicial, após clareamento e após escovação, foi determinada pela média (μm) de três leituras (em cada área sem e com ácido totalizando seis leituras por espécimes) com o rugosímetro Hommel Tester T 1000. Os valores médios do pH foram determinados pelo peagômetro digital Sentron Model 1001 nos tempos inicial e final. Os espécimes foram armazenados em saliva artificial por sete dias, submetidos a 100.000 ciclos de escovação simulada. Após 24 horas o desgaste superficial foi determinado (μm) empregando o mesmo rugosímetro. Em relação ao desgaste e a alteração de rugosidade superficial, os resultados foram submetidos à Anova a dois critérios e a dois critérios de medidas repetidas e posteriormente ao teste de Tukey. Os dados obtidos das leituras de pH foram submetidos à ANOVA a um critério e a dois critérios de medidas repetidas e ao teste de Kruskal Wallis e Tukey para comparações individuais entre os grupos. Para todos os testes o nível de significância foi de 5%. A rugosidade e o desgaste apontaram diferenças estatísticas entre os grupos, principalmente quando comparado à área com e sem ácido. Os géis clareadores apresentaram tendência de diminuição dos valores de pH do tempo inicial para o tempo final, contudo, uma correlação com a rugosidade e com o desgaste não pôde ser estabelecida de forma clara. / This in vitro study evaluated the influence of whitening activated with hybrid light on the function variations of the pH level and concentration of bleaching gels and prior acid etching of bovine enamel and the change in roughness and wear after simulated tooth brushing. Fragments of enamel (1.5 cm x 0.5 cm x 0.4 cm) were divided into two parts, one half as the control and the other as the test area. The latter was divided into two halves, one of which received the etching added to the whitening gel and the other with only the whitening gel. The specimens were randomly divided into six groups (n = 10): C = control; TBO35LH = 35% Total Blanc Office 1x session (5x8\') + activation with hybrid light LED/Laser; LPS35LH = 35% Lase Peroxide Sense - 1x session (5x8\') + activation with hybrid light LED/Laser; LPS25LH = 25% Sense Lase Peroxide - 1x session (5x8\') + activation with hybrid light LED/Laser; LPL15LH = 15% Lase Peroxide Lite - 1x session (5x8 \') + activation with hybrid light LED/Laser; LPL10LHV = 10% Lase Peroxide Lite - 1x session (5x8\') + activation with violet hybrid light LED/Laser. The arithmetic roughness (Ra) started after bleaching and after brushing was determined by averaging (μm) the three readings (in each area - with and without acid for a total of six readings per specimen) with a Rugosimeter Hommel Tester T 1000. The mean pH values were determined by the Sentron Model 1001 digital pH meter at the start and end times. The specimens were stored in artificial saliva for seven days, and subjected to 100,000 cycles of simulated brushing. After 24 hours, the surface wear was determined (μm) employing the same roughness meter. In relation to the change in wear and surface roughness, the results were evaluated by two way ANOVA testing for repeated measures and later, a Tukey\'s test. The data obtained from the pH readings were submitted to two way ANOVA testing for repeated measures and the Kruskal Wallis and Tukey tests for the comparisons between the individual groups. The significance level was set at 5% for all the tests. The roughness and wear showed statistical differences between the groups, especially when compared to the area with and without acid. The bleaching gels tended to decrease in pH from the starting time to the final time, however, a correlation with the roughness and wear could not be clearly established.

<p>Gleđ je supstrat adhezije direktnih i indirektnih ispuna, ljuspi, splintova, zalivača i ortodontskih bravica. Adhezija između materijala i zubnog tkiva je ključna za uspe&scaron;no sprovođenje različitih stomatolo&scaron;kih intervencija. Ova veza, bez obzira na brojnost i raznovrsnost novih materijala nije u potpunosti re&scaron;ena. CILJ: Ispitati mehaničke i hemijske osobine gleđi nakon tretmana različitim kondicionerima za pripremu gleđi. Odrediti tvrdoću i modul elastičnosti, odrediti hemijski udeo minerala kalcijuma i fosfata u povr&scaron;inskom sloju gleđi pre i posle nagrizanja različitim kiselinama i utvrditi uticaj prizmatičnosti gleđi na stepen nagrizanja gleđi primenom različitih kiselina. METODE: Sprovedeno je in vitro istraživanje na ekstrahovanim humanim zubima. U odnosu na primenjeni kondicioner analizirano je 192, od toga 96 uzoraka stalnih zuba i 96 uzoraka mlečnih zuba. Pripremljeni uzorci gleđi su analizirani pre i nakon primene četiri vrste kondicionera: 37% ortofosforne kiseline (Kerr, Gel etchant), 10% poliakrilne kiseline (GC, Dentin Conditioner), monomera estra fosforne kiseline (GC G bond), hidroksietilmetakrilata sa fosfornom kiselinom (3M Unitek, Transbond&trade; Plus Self Etching Primer). Određivana je tvrdoća i modul elastičnosti gleđi nanoindentacijom, struktura povr&scaron;inskog sloja gleđi pomoću skening elektronske mikroskopije, dok je hemijski sastav povr&scaron;inskog sloja gleđi određen metodom energetske disperzione spektroskopije. Rezultati modula elastičnosti unutar grupe mlečnih zuba ukazali su na postojanje statistički značajnih razlika između rezultata netretirane okluzalne povr&scaron;ine i svih tretiranih uzoraka okluzalne povr&scaron;ine, dok analiza tvrdoće gleđi u istoj grupi, ukazala je na statistički značajne razlike između vrednosti netretiranih i svih tretiranih uzoraka, na svim povr&scaron;inama, osim na uzorcima bukalne povr&scaron;ine tretiranih poliakrilnom kiselinom. U grupi stalnih zuba, postoje statistički značajne razlike vrednosti modula elastičnosti između uzoraka tretiranih ortofosfornom kiselinom, bez obzira na povr&scaron;inu zuba, u odnosu na grupe u kojima su kori&scaron;ćeni drugi kondicioneri, osim kada su poređeni uzorci lingvalne povr&scaron;ine stalnih zuba tretirani ortofosfornom kiselinom sa uzorkom - iste povr&scaron;ine tretirane Transbondom. Rezultati tvrdoće gleđi stalnih zuba pokazali su statistički značajne razlike između netretirane, kontrolne grupe i svih grupa testiranih kondicionera, bez obzira na ispitivanu povr&scaron;inu zuba. Svaki primenjeni kondicioner promenio je povr&scaron;insku morfologiju uzorka. Ortofosforna i poliakrilna kiselina, u najvećoj meri su uticala na pojavu polja nagrizanja tipa 1 i tipa 2. Primenom G bonda i Transbonda pored tipa 1, veliki udeo polja nagrizanja bio je tipa 5. Analiza hemijskih elemenata povr&scaron;inskog sloja gleđi uzoraka pre i nakon kondicioniranja ukazala je na smanjenje udela analiziranih elemenata, osim kiseonika čiji se maseni udeo povećao nakon tretmana sa svim kondicionerima u grupi stalnih i mlečnih zuba. ZAKLJUČAK: Vrednosti tvrdoće gleđi i vrednosti modula elastičnosti značajno se smanjuju nakon nagrizanja gleđi u stepenu koji je u zavisnosti od primenjenog kondicionera. Efekat nagrizanja aprizmatične gleđi je značajno manji u odnosu na stepen nagrizanja prizmatične gleđi, primenom svih testiranih kondicionera. Hemijski udeo minerala kalcijuma i fosfata u povr&scaron;inskom sloju gleđi je značajno niži posle nagrizanja u odnosu na vrednosti pre nagrizanja gleđi, međutim sam odnos Ca i P se ne menja.</p> / <p>Dental enamel is a substrate for the adhesion of direct and indirect fillings, venners, splints, fissure sealants and orthodontic brackets. Adhesion between the material and dental tissue is key to success of various interventions in dentistry. Despite the abundance and variety of new materials, adhesion has not been fully resolved. OBJECTIVES: To investigate the mechanical and chemical properties of the enamel after treatment with different conditioners. Determine the hardness and modulus of elasticity, the chemical content of calcium and phosphate minerals in the surface layer of the enamel before and after etching with different acids, and define the effect of enamel prismaticity on the degree of demineralisation by applying different acids. METHODS: An in vitro study was performed on extracted human teeth. In relation to the conditioner used, 192 were analyzed, of which 96 were permanent teeth and 96 were decidous teeth. Prepared enamel samples were analyzed before and after the application of four types of conditioner: 37% orthophosphoric acid (Kerr, Gel etchant), 10% polyacrylic acid (GC, Dentin Conditioner), phosphoric acid ester monomer (GC G bond), hydroxyethyl methacrylate with phosphoric acid ( 3M Unitek, Transbond &trade; Plus Self Etching Primer ). The hardness and modulus of elasticity of the enamel were determined by nanoindentation, the structure of the enamel surface layer by scanning electron microscopy, while the chemical composition of the enamel surface layer was determined by energy dispersive spectroscopy. RESULTS: The results of the modulus of elasticity within the group of decidous teeth indicated statistically significant differences between the results of untreated occlusal surface and all treated occlusal surface samples, while the analysis of the hardness of the enamel in the same group indicated statistically significant differences between the values of untreated and all treated samples, on all surfaces except buccal surface samples treated with polyacrylic acid. In the group of permanent teeth, there are statistically significant differences in the value of the modulus of elasticity between the samples treated with orthophosphoric acid, regardless of the tooth surface, compared to the groups in which other conditioners were used, except when the samples of the lingual surface of permanent teeth were treated with orthophosphoric acid in comparison to same sample group treated with Transbond. The results of the hardness of the permanent tooth enamel showed statistically significant differences between the untreated, control group and all groups of conditioners used, regardless of the tooth surface tested. Each conditioner applied changed the surface morphology of the sample. Orthophosphoric and polyacrylic acid, to a large extent, influenced the appearance of etching patterns type 1 and type 2. Using G bond and Transbond alongside to type 1, a large proportion of the etching pattern was type 5. Analysis of the chemical components of the surface layer of the enamel samples before and after conditioning indicated reduction of the proportion of analyzed elements, except for oxygen whose mass fraction increased after treatment with all conditioners in the permanent and deciduous teeth group. CONCLUSION: The values of the hardness of the enamel and the values of the modulus of elasticity decrease significantly after etching of the enamel to a degree that depends on the conditioner applied. The etching effect on aprismatic enamel is significantly smaller than the degree of demineralisation of the prismatic enamel in all conditioners tested. The chemical content of calcium and phosphate minerals in the surface layer of the enamel is significantly lower after the conditioning, however the Ca and P ratio does not change.</p>