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Thesis (M.S.)--University of Michigan, Ann Arbor, 1979. / Typescript (photocopy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 53-56).

Thesis (M.S.)--University of Michigan, Ann Arbor, 1985. / Typescript (photocopy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 66-71).

Thesis (M.S.)--University of Michigan, Ann Arbor, 1976. / Typescript (photocopy). eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 66-71).

Thesis (M.S.)--University of Michigan, 1953.

Diss. Nr. 11648 techn. Wiss. ETH Zürich. / Literaturverz.

Thesis (M.S.)--University of Michigan, 2003. / Includes bibliographical references.

Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this laboratory study was to determine if the bond strengths of composite resins and unfilled resins was affected similarly when applied to enamel surfaces which had been previously etched with 50 per cent phosphoric acid. The test specimens were subjected to 24 hours, 30 days, and 6 months storage in water and then subjected to temperature stress cycling and intermittent tensile stress cycling. A tensile test was used to measure the bond strengths of the composite resins (Adaptic and HL-72) and the unfilled resin (Sevriton). The following results were obtained: (1) Pretreating the enamel surface with 50 per cent phosphoric acid for 60 seconds significantly increased the bond strength of composite resins; (2) when placed on acid etched enamel, there was no significant difference in initial bond strengths obtained for the Adaptic and unfilled Sevriton resins; (3) with prolonged water storage, the Adaptic composite resins developed significant loss of bond strength when compared to the unfilled Sevriton resins and the composite HL-72 resins; (4) when Adaptic resins and the HL-72 resin specimens were compared, there was no significant difference in initial bond strengths but the HL-72 specimens were less affected by storage time. Ca45 was used to assess the marginal seal of Adaptic, HL-72, and Sevriton in acid etched and non-etched Class V restorations. One-half of the specimens were thermal cycled 2500 times and stored in water for one week. Control specimens were tested at the end of one week without the thermal cycle. On the basis of these results, it was concluded that acid etching enhances the marginal seal of both composite and unfilled resins. Both composite and unfilled resins experienced increased marginal leakage when the acid etch preparations were thermal cycled, but there were no observable difference in the marginal seal of unfilled resins and composite resins when placed in acid etched restorations.

Området submarin miljö och dentala förhållanden finns det få studier inom. Detta ger behandlare svårigheter att ta evidensbaserade behandlingsbeslut för grupper som utsätts för hyperbariskt tryck. För att kunna föra fram kvalitativa studier och odontologisk kunskap krävs tillförlitliga metoder. Syfte: Syftet är att utvärdera om den presenterade metoden är tillförlitlig när det gäller att utvärdera exponering för tryck över atmosfärstryck har en inverkan på mikroläckage av temporära restaureringsmaterial. Material och metod: 27 extraherade tänder utan visuella defekter, preparerades under standardiserade former och fyllda med glasjonomermaterial. Dessa objekts rötter kapades och två lager av bonding applicerades som blockering av infärgning. Dessa 27 objekt delades in i 3 grupper trycktes i tryckkammare till 1, 3, respektive 5 bar, liggandes i infärgning med 2% metylenblått. Dessa sektionerades och granskades visuellt enligt binära mätmetoder under förstoringsobjektiv. Resultat: Resultatet var liknande mellan grupperna oavsett utsatt tryck. Samtliga testade objekt visade på permeabilitet i tand-fyllningsgränsen. 77,8-100% av objekten hade infärgningsläckage från dentintubuli via pulpakavum sett till alla grupper. Glasjonomerfyllningar visade ingen mätbar permeabilitet i något objekt. Persisterande glasjonomer-glaze noterades på 55,6-66,6% av testobjekten beroende på testgrupp. Slutsats: Några av faktorerna inkluderade i den presenterade metoden behöver övervägas på nytt och möjligtvis ändras innan en mer tillförlitlig metod för syftet kan etableras. De faktorer som här syftas till är relaterade till termocykling, sektionering av testobjekt, utvärdering av testresultat, blockering av permeabilitet-indikator, mätning av läckage av permeabilitet-indikator, och användning av glasjonomer-glaze. / There are few studies in the area of ​​dental material science concerning submarine environments. This gives practitioners difficulties in making evidence-based decisions in the treatment of the group of patients who are exposed to hyperbaric pressures. In order to carry out qualitative studies and further odontologic knowledge in this field, reliable methods are required. Aim: The purpose of this study is to evaluate whether the presented method is reliable and accurate in evaluating and measuring micro-leakage of temporary restoration materials exposed to hyperbaric pressures. Materials and methods: 27 extracted teeth without visual defects were prepared under standardized forms and filled with glass ionomer material. The roots of the teeth were cut, and two layers of bonding were applied in the pulpal cavities as blockage for the dye. The teeth were divided into 3 groups, the groups were pressurized to 1, 3 and 5 bar respectively, lying in 2% methylene blue dye. The teeth were sectioned and visually inspected according to binary criteria standards under magnification lens. Results: Similar results irrespective of what pressurized environment they had been subject to were seen. Every test object displayed permeability along both the tooth-filling interface. A high incidence rate(=77,8-100%) of dye permeability via dentinal tubules through the open pulpal cavities was seen in all groups. The glass-ionomer material body showed no significant permeability of the dye for either of the subjects. Persistent glass-ionomer glaze was noted in each group, with an incidence of 55,6-66,6%. Conclusions: Some of the factors included in the presented method need to be reevaluated and perhaps be changed before a more reliable method for the purpose can be established. These considered factors are related to thermal cycling, slicing of test objects, test result evaluation, blockage of permeability indicator, measurement of permeability indicator leakage, and usage of glass-ionomer glaze.

O objetivo neste trabalho foi avaliar a influência da variação do tempo de fotopolimerização para diferentes cores (I, B1, B3 e C4) de uma resina composta (FiltekTM Z250, da 3M ESPE), sobre a taxa de desgaste abrasivo através do método do disco retificado. Cada espécime de resina composta fotopolimerizada estava contido numa cavidade semicircular localizada na periferia de um disco constituído por polimetilmetacrilato (PMMA), denominado disco estático, sendo que a superfície curva da resina no disco sofria desgaste por um rebolo de porcelana, denominado tecnicamente de disco dinâmico, sob carga padronizada e velocidade controlada, criando no espécime uma cavidade de aspecto semicircular. O deslocamento vertical do disco estático, ao ser desgastado, era detectado por um palpador, o qual transferia estes dados a um computador e criava os arquivos de desgaste, em função do tempo. Os dados obtidos foram tratados estatisticamente. Pôde-se concluir que 1) a resistência à abrasão do PMMA foi a maior de todas e 2) a resina de cor C4, a mais resistente de todas. / The aim at this study was estimate the influence of light-curing time variation of different colors (I, B1, B3 and C4) of composite resin (FiltekTM Z250, 3M ESPE), upon abrasive wear through the retified disc method. The porcelain existent in the named dynamic disc promoted a wear of each resin specimen located in the polimethylmetacrylate (PMMA) static disc, under a standardized charge and with controlled velocity. Vertical displacement of static disc was detected by a sensor that send data to a computer where wear arquives were plotted in function of time. After data statistical analysis, it could be concluded that: 1) PMMA resistance was greater than anyone of resins and 2) C4 was more resistant than all the other colors.