• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 106
  • 6
  • 3
  • 3
  • 3
  • 3
  • 3
  • 3
  • 2
  • 2
  • 2
  • 2
  • 1
  • Tagged with
  • 125
  • 125
  • 105
  • 99
  • 63
  • 43
  • 38
  • 37
  • 32
  • 23
  • 21
  • 21
  • 17
  • 16
  • 14
  • 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.
121

Dentalne erozije i karijesne promene kod pacijenata na dugogodišnjoj inhalatornoj terapiji / Dental erosions and caries lesions in patients on long-term inhalation therapy

Velicki-Bozejac Branislava 25 November 2016 (has links)
<p>Uvod: Astma i hronična opstruktivna bolest pluća (HOBP) najče&scaron;će su hronične respiratorne bolesti u čijoj terapiji prednost imaju inhalatorni lekovi. Pacijenti na inhalatornoj terapiji imaju povećan rizik od nastanka dentalnih erozija i karijesnih lezija, usled promena u količini lučenja pljuvačke i njene pH vrednosti. Cilj: Cilj ovog istraživanja je verifikacija dentalnih erozija i karijesnih lezija kod pacijenata s astmom i hroničnom opstruktivnom bolesti pluća, koji koriste inhalatornu terapiju. Materijal i metode rada: Istraživanjem je obuhvaćeno 80 ispitanika, životne dobi od 18 do 65 godina. Eksperimentalnu grupu sačinjavalo je 40 ispitanika, s dijagnostikovanom astmom ili hroničnom opstruktivnom bolesti pluća, koji uzimaju inhalatornu terapiju duže od 5 godina. Kontrolnu grupu činilo je 40 zdravih ispitanika istog godi&scaron;ta i pola kao u eksperimentalnoj grupi. Upitnik se koristio za prikupljanje podataka o osnovnom oboljenju, simptomima koji se mogu javiti kao nuspojave inhalatornih lekova, navikama, ishrani i održavanju oralne higijene. Kliničkim stomatolo&scaron;kim pregledom određeni su erozivni indeks, KEP indeks, indeks krvarenja iz interdentalne gingive i indeks mekih naslaga na zubima. Laboratorijskim ispitivanjem određeni su količina izlučene nestimulisane pljuvačke, te pH vrednost i koncentracije kalcijuma i fosfata u pljuvački. Rezultati: Kod pacijenata na inhalatornoj terapiji ustanovljena je vi&scaron;a prevalencija dentalnih erozija i karijesnih lezija, te vi&scaron;e vrednosti indeksa krvarenja iz interdentalne gingive i indeksa mekih naslaga na zubima, u odnosu na ispitanike kontrolne grupe. U eksperimentalnoj grupi ispitanika količina i pH vrednosti nestimulisane pljuvačke su statistički značajno niže u odnosu na ista obeležja kontrolne grupe. Vrednosti koncentracije kalcijuma u pljuvački između ispitivanih grupa se ne razlikuju statistički značajno. Vrednosti koncentracije fosfata u eksperimentalnoj grupi ispitanika su statistički značajno vi&scaron;e nego u kontrolnoj grupi ispitanika. Zaključak: Pacijenti na inhalatornoj terapiji spadaju u grupu osoba s visokim rizikom od nastanka dentalnih erozija i karijesnih lezija. Uvođenje lokalne strategije preventivnih mera, te uspostavljanje međusobne saradnje stomatologa i lekara &ndash; pulmologa, dovelo bi do očuvanja i unapređenja zdravlja zuba kod pacijenata na inhalatornoj terapiji.</p> / <p>Introduction: Asthma and chronic obstructive pulmonary disease (COPD) are predominant chronic respiratory diseases in whose treatment a priority is given to inhalation drugs. The patients receiving inhalation therapy are at an increased risk of dental erosion and caries lesions due to changes in the amount of salivary flow rate and its pH value. Objective: The study objective was to investigate the prevalence of dental erosion and caries lesions in patients with asthma and chronic obstructive pulmonary disease who use inhalation therapy. Materials and methods: The study included 80 participants between the age of 18 and 65. The experimental group comprised of 40 participants previously diagnosed with asthma or chronic obstructive pulmonary disease undergoing inhalation therapy for more than 5 years. The control group involved 40 healthy participants of the same age and gender status as those in the experimental group. The questionnaire was designed to collect informations on underlying disease, symptoms that can occur as side effects of inhaled drugs, habits, dietary and oral hygiene habits. The clinical dental examination established the basic erosive wear examination (BEWE index), DMFT index, papilla bleeding index (PBI) and dental plaque index. The laboratory investigation comprised measurements of the salivary flow rates of non-stimulated saliva, pH value and calcium and phosphate concentrations in the saliva. Results: The subjects receiving inhalation therapy were found to have a higher prevalence of dental erosion and caries lesion as well as higher mean papilla bleeding index scores and mean plaque index scores in comparison to the control group. In the experimental group, the mean value of the salivary flow rate and pH value were lower as compared to the control group. Calcium concentrations in the saliva were similar in both groups, but the results were not statistically significant. However, phosphate concentration was statistically significantly higher in the experimental group than in the control group. Conclusion: The patients undergoing inhalation therapy have a high risk of dental erosion and caries lesion. The introduction of local strategy of preventive dental care and establishing mutual cooperation between dentists and pulmonary specialists would contribute to the promotion and preservation of the dental health in the patients on inhalation therapy.</p>
122

Resistência de união à dentina erodida e erodido-abrasionada em função da aplicação de clorexidina para controle do desgaste / Bond strength to eroded and eroded-abraded dentin depending on the application of chlorhexidine for the control of tooth wear

Liberatti, Giovanni Aguirra 04 February 2019 (has links)
O estabelecimento de interfaces adesivas no substrato dentinário artificialmente erodido, conceitualmente pobre em minerais, revestido por matriz orgânica exposta, é pouco promissor. Por ora, tornam-no similar àquele verificado para a dentina normal/hígida apenas a asperização ou, quando do uso de adesivos universais, a desproteinização com hipoclorito de sódio. Manter a camada de fibrilas colágenas, por meio do uso de inibidores de proteinases, talvez mesmo que compactada por abrasão, pode, porém, ser conveniente, já que desempenha importante papel nos processos de des e remineralização, inclusive contendo a progressão do desgaste erosivo e erosivo-abrasivo, e no estabelecimento de uma camada híbrida propriamente dita. Avaliou-se, pois, de imediato, a resistência de união do conjunto sistema adesivo condicione e lave simplificado-resina composta à dentina, considerando-se como fatores experimentais a condição desse substrato, em três níveis (N: normal; E: erodido; EA: erodido-abrasionado), e a aplicação de um gel para prevenção/controle do desgaste erosivo em três níveis (C: controle/sem aplicação; P: placebo/sem princípio ativo; CHX: digluconato de clorexidina a 0,12%). Para determinação do substrato normal, a dentina superficial oclusal de terceiros molares foi apenas submetida à ação de uma lixa de SiC (#600; 1 min; N); para a do erodido e do erodidoabrasionado, sequencialmente, de pronto, a desafio erosivo inicial (Coca-Cola®; 5 min). Aplicou-se sobre ela, então, ou não (controle/sem aplicação), um dos géis: placebo/sem princípio ativo; ou à base de CHX a 0,12%. Aquela de início desmineralizada ainda foi submetida à ciclagem de pH (Coca-Cola®; imersões de 5 min, 3x/dia, 5 dias), determinando-se, fatidicamente, o substrato erodido (E), ou a ciclagem de pH associada a escovação (escova elétrica/dentifrício com flúor diluído em água, 2,5 N, 30 s, 2x/dia, após 1º e último desafios ácidos), determinando-se o substrato erodido-abrasionado (EA). Após condicionamento (H3PO4 a 37%; 15 s; lavagem 30 s; secagem com papel absorvente), o adesivo AdperTM Single Bond 2® foi aplicado em todos os espécimes e a porção coronária, reconstruída com a resina FiltekTM Z350®. Transcorridas 24 h (água destilada / 37?C), os espécimes foram seccionados em palitos e testados (?TBS; 0,5 mm/min). Os valores de RU obtidos foram organizados considerando-se cada dente como unidade experimental e os testes de Análise de Variância a 2 critérios e de Tukey, aplicados (?=0,05). Um dente extra para cada grupo foi tratado exatamente como os outros, mas o corante fluorescente rodamina B foi previamente adicionado (0,16 mg/mL) ao sistema adesivo para permitir a avaliação qualitativa da interface adesiva por meio de Microscopia Confocal de Varredura a Laser. Diferentemente da variável aplicação de géis para prevenção/controle do desgaste erosivo (p=0,359), a variável condição do substrato dentinário exerceu influência significante sobre os resultados (p<0,001). Ademais, não houve interação entre elas (p=0,856). Os valores imediatos de RU ao substrato erodido e ao erodido-abrasionado, equivalentes entre si, foram sempre inferiores àqueles ao substrato normal, independentemente da aplicação, ou não, do gel de CHX, ou placebo, para prevenção/controle do desgaste erosivo. No tocante ao padrão de fratura dos palitos testados, as falhas adesivas e mistas foram predominantes em relação às coesivas, independentemente se em dentina ou em resina. Quanto à análise qualitativa, nota-se que tags resinosos se manifestam em maior número e comprimento nos substratos submetidos a desafio erosivo inicial, ou seja, o erodido e o erodido-abrasionado, independentemente da aplicação de qualquer estratégia para controle da progressão do desgaste. Dentre eles, para o substrato erodido, há uma identificável camada escura subjacente à de adesivo propriamente dito, entre os tags resinosos, representação da menor concentração de material marcado por rodamina B. Para o substrato erodido-abrasionado, verifica-se camada híbrida devidamente expressa por anuviado vermelho subjacente à camada de adesivo, mais e menos espessa, respectivamente, que a estabelecida no substrato normal e erodido. Destarte, conclui-se que o gel de CHX não foi capaz de determinar, por meio da preservação/controle do desgaste erosivo, ou erosivo-abrasivo, substrato tão favorável à adesão com os materiais resinosos quanto o normal, mesmo que não o tenha desajudado ainda mais. / The establishment of adhesive interfaces on artificially eroded dentin substrate, conceptually poor in minerals, coated with an exposed organic matrix, is little promising. For the time being, only diamond bur surface roughening and deproteinization with sodium hypochlorite, when universal adhesives are used, make it similar to the obtained for normal/sound dentin. Maintaining the layer of collagen fibrils, using protease inhibitors, perhaps even when compressed by abrasion, may, however, be convenient, since it plays an important role in the demineralization and remineralization processes, including the erosive and erosive-abrasive wear progression, and in establishing a hybrid layer itself. The aim of this study was to evaluate, immediately, bond strength (BS) of an etch-and-rinse adhesive system plus a composite to dentin, considering the condition of its substrate in three levels (N: normal; E: eroded; EA: eroded-abraded), and the application of a gel for the prevention/control of the erosive wear in three levels (C: control / without application, P: placebo / without an active principle, and CHX: 0.12% chlorhexidine digluconate). To determine the normal substrate, occlusal dentin from third molars was subjected solely to the action of a SiC sandpaper (# 600; 1 min; N); to determine the eroded and eroded-abraded, it was sequentially, and readily, subjected to an initial erosive challenge (Coca-Cola®, 5 min). One of the gels were applied, or not (control / without application), on it: placebo / without active principle; or containing 0.12% CHX. The initial demineralized one was still submitted to a pH cycling (Coca-Cola®, immersions of 5 min, 3x /day, 5 days), determining the eroded substrate (E), or to the pH cycling associated to brushing (electric toothbrush/fluoride toothpaste diluted in water, 2.5 N, 30 s, 2x/day, after 1st and last acid challenges), determining the eroded-abraded substrate (EA). After acid-etching (37% H3PO4, 15 sec, 30 sec washing, drying with absorbent paper), Adper(TM) Single Bond 2® adhesive was applied to all specimens and resin composite buildups constructed with Filtek(TM)Z350®. After 24 h (distilled water / 37?C), specimens were sectioned in beams and tested (?TBS, 0.5 mm/min). BS values obtained were organized considering each tooth as an experimental unit and a twoway ANOVA and Tukey test, applied (?=0.05). An extra tooth for each group was treated exactly like the others, but rhodamine B fluorescent dye was previously added (0.16 mg / mL) to the adhesive system to allow qualitative evaluation of the adhesive interface by means of Confocal Laser Scanning Microscopy. Differently from the variable application of gels for prevention/control of erosive wear (p=0.359), the condition of the dentin substrate had a significant influence on the results (p<0.001). In addition, there was no interaction between them (p=0.856). Immediate BS values to eroded and eroded-abraded substrates, equivalent to each other, were always lower than that to the sound substrate, regardless of the application, or not, of the CHX or the placebo gel for prevention/control of erosive wear. Concerning the fracture pattern of the tested beams, adhesive and mixed failures were predominant in relation to the cohesive, regardless of whether in dentin or in resin composite. As for the qualitative analysis, it is noticed that resinous tags are manifested in greater number and length in the substrates submitted to erosive initial challenge, that is, eroded and erodedabraded substrates, regardless of the application of any strategy to control progression of wear. Among them, for the eroded substrate, there is an identifiable dark layer underlying that of the adhesive itself, among the resin tags, representing the lowest concentration of material marked by rhodamine B. For the eroded-abraded substrate, hybrid layer is duly expressed by a red blur underlying the layer of adhesive, more and less thick than that established in the normal and eroded substrates, respectively. Therefore, it is concluded that the CHX gel was not able to determine, while preserving/controlling the erosive or erosive-abrasive wear, a substrate as favorable to bonding with resinous materials as a sound one, even if it has not impaired it even more.
123

Interaction between tin/flouride-containing solutions and artificially created dental pellicles on erosion prevetion in vitro

Algarni, Amnah Abdullah A. January 2013 (has links)
Indiana University-Purdue University Indianapolis (IUPUI)School of dentistry / BACKGROUND: Fluoride and stannous ions have been reported to be relevant for dental erosion prevention. However, their interaction with the acquired dental pellicle (ADP), a clinically relevant erosion protective factor, is not well known and needs to be investigated. OBJECTIVES: To investigate the anti-erosive properties of fluoride-containing solutions and stannous solutions on enamel and dentin surfaces with a previously formed ADP. To characterize the protein profile of the ADP treated with the test solutions. METHODS: Phase I tested four solutions: SnCl2/NaF, NaF, SnCl2 and deionized water (DIW) (as negative control). Forty bovine enamel and dentin specimens 104 (4x4x2 mm3) were prepared and randomly distributed into 4 groups (n = 10). The specimens were incubated in clarified human saliva (CHS) for 24 h for pellicle formation and then they were subjected to a cycling procedure that included a 5-min erosive challenge (0.3-percent citric acid, pH 2.6); a 2-min treatment with the solution (between 1st, 3rd and 6th cycles); a 2-h immersion in CHS, and overnight immersion in CHS. Cycles were repeated 6x/day for 5 days. The outcome measure was surface loss (SL) using profilometry. Phase II: Thirty-two (32) bovine enamel specimens (882 mm3) (n = 8) were similarly prepared and incubated in saliva for 24 h and then treated with the solutions for 2 min followed by CHS immersion for 2 h. This cycle was repeated 3x for one day. The pellicles formed and treated with the test rinse solutions were collected, digested, and analyzed for specific protein content using liquid chromatography electrospray ionization tandem mass spectrometry (LCESI-MS/MS). RESULTS: Phase I: for enamel, SnCl2/NaF, SnCl2, NaF solutions provided 89 percent, 67 percent, and 42 percent SL reduction respectively compared with the control, while in dentin they provided 60 percent, 23 percent, and 36 percent, respectively, all significant at p < 0.05. Phase II: Seventy-two (72) common proteins were identified in all groups, 30 exclusive to DIW, 20 to SnCl2/NaF, 19 to NaF, and 13 to SnCl2. SnCl2/NaF increased the abundance of pellicle proteins than each one alone. CONCLUSION: SnCl2/NaF showed the best anti-erosive effect on both enamel and dentin. The findings suggest that the composition of acquired pellicle changes with different solutions, which may be related to their anti-erosive effect.
124

Chlorhexidine does not improve but preserves bond strength to eroded dentin.

Francisconi dos Rios, Luciana Fávaro, Calabria, Marcela Pagani, Casas-Apayco, Leslie, Honório, Heitor Marques, Carrilho, Marcela Rocha De Oliveira, Pereira, José Carlos, Wang, Linda 02 1900 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / PURPOSE: To evaluate the effect of aqueous solutions of chlorhexidine digluconate (CHX) in different concentrations on bond strength to eroded dentin up to 6 months, using normal dentin as a control. METHODS: Exposed flat dentin of extracted third molars was only ground with 600-grit SiC paper/1 minute (normal dentin - N), or subsequently eroded by a regular-cola soft-drink (eroded dentin - E). N and E were acid-etched, washed, dried and rehydrated with 1.5 μL, respectively, of distillated water (control - NC / EC); of 0.004% CHX (N0.004% / E0.004%); or of 2% CHX (N2% / E2%). Adper Single Bond 2 was applied in all specimens and resin composite buildups were constructed with Filtek Z350. Specimens were sectioned in beams, which were tested (μTBS) immediately or after 6 months of aging. RESULTS: Microtensile bond strength to eroded dentin was always significantly lower than that to normal dentin. Application of tested CHX solutions did not exert a significant effect immediately; however, after aging, the 2% CHX prevented abrupt bond strength loss both to eroded and normal dentin. / Revisión por pares
125

Effect of simulated intraoral erosion and/or abrasion effects on etch-and-rinse bonding to enamel.

Wang, Linda, Casas-Apayco, Leslie, Hipólito, Ana Carolina, Dreibi, Vanessa Manzini, Giacomini, Marina Ciccone, Bim Júnior, Odair, Rios, Daniela, Magalhães, Ana Carolina 02 1900 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / PURPOSE: To assess the influence of simulated oral erosive/abrasive challenges on the bond strength of an etch-and-rinse two-step bonding system to enamel using an in situ/ex vivo protocol. METHODS: Bovine enamel blocks were prepared and randomly assigned to four groups: CONT - control (no challenge), ABR - 3x/day-1 minute toothbrushing; ERO - 3x/day - 5 minutes extraoral immersion into regular Coca Cola; and ERO+ABR - erosive protocol followed by a 1-minute toothbrushing. Eight blocks were placed into an acrylic palatal appliance for each volunteer (n = 13), who wore the appliance for 5 days. Two blocks were subjected to each of the four challenges. Subsequently, all the blocks were washed with tap water and Adper Single Bond 2/Filtek Z350 were placed. After 24 hours, 1 mm2 beams were obtained from each block to be tested with the microtensile bond strength test (50 N load at 0.5 mm/minute). The data were statistically analyzed by one-way RM-ANOVA and Tukey's tests (alpha = 0.05). RESULTS: No difference was detected among the ABR, ERO, and CONT groups (P > 0.05). ERO+ABR group yielded lower bond strengths than either the ABR and ERO groups (P < 0.0113). / Revisión por pares

Page generated in 0.0724 seconds