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Thesis (doctoral)--University of Göteborg, 1992. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Thesis (doctoral)--University of Göteborg, 1992. / Added t.p. with thesis statement inserted. Includes bibliographical references.

Dentine caries has a microbiological aetiology whilst the diagnosis relies on clinical signs. This study examined relationships between the Locations, Colours, Textures, Sizes, Perceived Treatment Needs, Cavitations and microbiological characteristics of Primary Root Caries. The relationships between some microflora of Primary Root Caries deemed to require restoration and the overlying plaque as well as the effects of a Chemotherapeutic agent on some microflora of lesions were also studied. In all, 610 lesions in 303 patients were investigated. 447 lesions in 169 patients were examined in the main study. The Locations of lesions were related to the gingival margins; Colours were designated: Black, Yellow, Light Brown or Dark Brown; Textures were recorded as Hard, Leathery or Soft, Sizes as products of Heights and Widths, and Cavitations as the greatest loss of surface contour. The total numbers of colony forming units ; Gram-positive pleomorphic rods; Mutans streptococci; Lactobacilli; and Yeasts expressed as Log1p as well as the proportions and Frequency of isolation, in each dentine biopsy were determined, eg - 90.9 percent of Soft but only 3.3 percent of Hard lesions were <1 mm from gingivae (P < 0.001); - 68.6 percent of Soft but only 6.7 percent of Hard lesions were sized >7 mm2 (P < 0.01); - more cavitated lesions were larger (P < 0.01); - higher total numbers, proportions and frequencies of isolation of Mutans streptococci and Lactobacilli were in Soft and Leathery than in*Hard lesions (P < 0.01); - the mean total numbers of colony forming units, Mutans streptococci, Lactobacilli and Gram-positive pleomorphic rods were less in each group of lesions with a reduced Perceived Treatment Need (P < 0.01); - lesions deemed to require restoration most frequently contained Yeasts (P < 0.01); - the most reliable indicators of microbiological activity were Texture and Location rather than Colour; From 81 Primary Root Caries lesions deemed to require restoration in 52 patients, not amongst the 169 in the larger study, higher proportions of Gram-positive pleomorphic rods (P < 0.001) and Lactobacilli (P < 0.01) were in carious dentine than in the associated plaque, indicating that precision in sampling is paramount. 42 of 82 lesions deemed to require restoration in another 82 patients, were coated with a varnish containing 1 weight (wt) percent chlorhexidine and 1 wt percent thymol and after 24 hours these and the lesions not varnished were biopsied. The varnish significantly reduced the numbers of micro-organisms (total colony forming units, P<0.001; Mutans streptococci, Lactobacilli and Yeasts, P<0.01). These studies will help clinicians and epidemiologists to diagnose the levels of activity in Primary Root Caries and to indicate how Chemotherapy rather than the removal of carious dentine might be developed as a preferred strategy for its management.

Indiana University-Purdue University Indianapolis (IUPUI) / Purpose: This in vitro study aims to analyze the effect of combining two ADA-recommended professionally applied 1:1 Chlorhexidine/Thymol varnish ((Cervitec Plus)) and professionally prescribed 5,000 ppm fluoride toothpaste ((PreviDent 5000 Plus)) on reducing lesion depth and increasing mineral content Materials & Methods: Forty-eight dentin specimens were randomly distributed into four treatment groups (n=12 per treatment). Biofilms of Streptococcus mutans and Candida albicans were created on the polished surfaces of bovine root dentin specimens (n=12 per treatment). 1:1 Chlorhexidine/Thymol varnish was applied once then the tested 5,000 ppm fluoride toothpaste was applied for 120 seconds twice daily over the course of 2 days. Tested groups were: (1) 1:1 Chlorhexidine/Thymol varnish ((Cervitec Plus)) (C/T). (2) 5,000 ppm F toothpaste ((PreviDent 5000 Plus)) (F). (3) Combination of 1:1 Chlorhexidine/Thymol varnish ((Cervitec Plus)) & 5000 ppm F toothpaste ((PreviDent 5000 Plus)) (C/T+F). (4) Deionized water (DIW) as control group. Biofilms were analyzed for biofilm dry weight. Dentin specimens were analyzed using transversal microradiography (TMR) for mineral content change and lesion depth. PH data was analyzed using two-way ANOVA. Total biofilm dry weight data was analyzed using one-way ANOVA. Integrated mineral loss and lesion depth data was analyzed using two-way ANOVA All pair-wise comparisons from ANOVA analysis were made using Fisher’s Protected Least Significant Differences to control the overall significance level at 5%. Results: Treatment with (C/T+F) resulted in higher mean pH values compared to the control group (DIW) and (F) group. The average pH values of group (C/T) were not statistically different than group (C/T+F). the biomass of the combined S. mutans & C. albicans biofilm among all the groups were not significantly different. (DIW) presented significantly deeper lesions for both surfaces (sound &demineralized) when compared to (F) (P=0.0118), (C/T) (P=0.0002), and (C/T+F) (P<.0001). The sound surfaces for the specimens for group (C/T) and Group (F) showed superficial lesion depth. However, the sound surfaces of specimens treated with (C/T+F) showed the most superficial depth. Due to mineral gain, the demineralized surfaces of the specimens of both (C/T) & (C/T+F) showed a decrease in the lesion depth. Conclusion: Within the limitations of our study. The combination of 5,000 ppm fluoride toothpaste and CHX/Thymol had no significant effect on mineral content. However, the combination had a considerable effect on lesion depth reduction.

Objetivo: Este estudo avaliou a influência do uso de diferentes lasers, associados ou não à aplicação de fluoreto de sódio, na prevenção da cárie radicular. Materiais e Método: Para este estudo, 128 espécimes de dentina radicular humana (4,25mm X 4,25mm e 3,00mm de espessura) foram divididos aleatoriamente em 8 grupos: (G1=nenhum tratamento, G2=aplicação de flúor gel, G3=irradiação com o laser Er:YAG, G4=aplicação de flúor gel + irradiação com o laser Er:YAG, G5=irradiação com o laser Nd:YAG, G6=aplicação de flúor gel + irradiação com o laser Nd:YAG, G7=irradiação com o laser CO2, G8=aplicação de flúor gel + irradiação com o laser CO2. Para os grupos que receberam irradiação laser , metade do espécime foi irradiada (&asymp;9,00mm2) e a outra metade não (região controle). Nos grupos que receberam flúor gel, este foi aplicado antes da irradiação laser por 4 minutos. Após o tratamento dos espécimes, estes foram submetidos a desafios cariogênicos (ciclos de pH) em soluções desmineralizante (pH=5,0) e remineralizante (pH=7,0), por 6 horas e 18 horas, respectivamente, completando um período experimental de 14 dias. A avaliação dos tratamentos realizados nos grupos experimentais foi feita através dos seguintes testes: 1-) mensuração da porcentagem de desmineralização através de microscopia óptica MO; 2-) avaliação da morfologia da superfície irradiada através de microscopia eletrônica de varredura MEV; 3-) análise da microdureza das paredes de fundo da dentina radicular desmineralizada em diferentes profundidades através do teste de microdureza longitudinal; 4-) quantificação da porcentagem dos elementos cálcio, fósforo e flúor através de micro análise por energia dispersiva de raios X EDS. Os dados foram submetidos a diferentes testes estatísticos, dependendo da propriedade analisada. Resultados: Os lasers Nd:YAG e CO2 foram mais eficazes na diminuição da porcentagem de desmineralização do que o laser Er:YAG. A menor porcentagem de desmineralização foi observada no G7. Na microscopia eletrônica da varredura, o laser Er:YAG proporcionou mudanças mais satisfatórias que os demais, na medida em que observou-se uma dentina mais lisa e homogênea, sem trincas ou áreas de carbonização. O laser Er:YAG também foi superior no aumento da resistência ácida da dentina, quando avaliada pelo teste de microdureza. O G3 obteve os maiores valores médios de microdureza Knoop. Em relação à análise de EDS, houve uma tendência de incorporação do flúor nas áreas irradiadas, principalmente após irradiação com os lasers Er:YAG e CO2. Conclusões: Todos os lasers testados apresentaram resultados promissores na prevenção da cárie radicular e, para as propriedades analisadas, não houve sinergismo resultante da aplicação de flúor gel previamente à irradiação laser. / Objective: This study evaluated the influence of different lasers, associated or not with sodium fluoride application, in the prevention of root caries. Materials and Methods: For this study, 128 specimens of human root dentin (4.25mm X 4.25mm and 3.00mm thick) were randomly divided into 8 groups: (G1=no treatment, G2=application of fluoride gel, G3= Er:YAG laser irradiation, G4=application of fluoride gel + Er:YAG laser irradiation, G5= Nd:YAG laser irradiation, G6=application of fluoride gel + Nd:YAG laser irradiation, G7= CO2 laser irradiation, G8= application of fluoride gel + CO2 laser irradiation. For the groups that received laser irradiation, half of the specimen was irradiated (&asymp;9.00mm2) and the other half was not (control region). In the groups that received fluoride gel, this was applied before laser irradiation for 4 minutes. After treatment of samples, these were submitted to a cariogenic challenge (pH cycles) in demineralizing (pH=5.0) and remineralizing (pH=7,0) solutions for 6 hours and 18 hours, respectively, completing an experimental period of 14 days. The evaluation of the proposed treatments in the experimental groups was performed using the following tests: 1-) measurement of the percentage of demineralization by light microscopy MO; 2-) assessment of the morphology of the irradiated surface by scanning electron microscopy MEV; 3-) microhardness analysis of the bottom walls of demineralized root dentin at different depths through the test of longitudinal microhardness; 4-) quantification of the percentage of the elements calcium, phosphorus and fluoride through micro analysis by energy dispersive X-ray - EDS. Data were submitted to different statistical tests, depending on the analyzed property. Results: Nd:YAG and CO2 lasers were more effective in decreasing the percentage of demineralization than the Er:YAG laser. The lowest percentage of demineralization was observed in the G7. In the scanning electron microscopy, the Er:YAG laser provided more satisfactory changes than the others, considering that there was a more smooth and homogeneous dentine, without cracks or carbonization areas. The Er:YAG laser was also greater in increasing the acid resistance of the dentin, when evaluated by microhardness test. The G3 obtained the highest average values of Knoop microhardness. Regarding the analysis of EDS, there was a tendency of incorporating fluoride in the irradiated areas, especially after irradiation with Er:YAG and CO2 lasers. Conclusions: All the tested lasers showed promising results in the prevention of root caries and for the analyzed properties, no synergism resulting from the application of fluoride gel prior to laser irradiation was found.

Os microrganismos associados à cárie são, em sua maioria, microrganismos acidogênicos e acidúricos, anaeróbios estritos e facultativos. A presença de fungos é associada à microbiota de cárie radicular, sendo a espécie fúngica mais relacionada a Candida albicans. Embora estudos de cultivo e de análise de DNA comprovem a presença de fungos na microbiota associada a lesões de cárie radicular, demonstrando um gradiente crescente de colonização com a progressão da doença, pouco se sabe sobre o papel que estes microrganismos desempenham no processo de doença. O objetivo deste trabalho foi estudar o papel de Candida albicans na cárie radicular, através da análise de transcriptoma de biofilmes naturais de superfícies radiculares hígidas (n=10, SRS) e de lesão de cárie radicular ativa (n=9, RC). Foi avaliada a expressão diferencial de genes de Candida albicans, as funções específicas e vias metabólicas associadas a este microrganismo. O RNA total microbiano foi extraído e o mRNA isolado e sequenciado na plataforma Illumina Hi-Seq2500. Foram formados pool (grupamentos) das amostras com valores inferiores a 30ng/RNA para a construção de bibliotecas genômicas. Os dados gerados pelo sequenciamento de RNA-Seq foram compilados em uma tabela de contagem (reads) e mapeados com o genoma de referência (C. albicans SC5314) utilizando o software CLC Genomics Workbench 7.5.1. Para o cálculo do nível de expressão gênica os dados foram normalizados com o algoritmo DESeq. A expressão diferencial foi calculada com binomial negativa e False Discovery Rate (FDR<0,05). Os genes com maior expressão em RC e em SRS foram analisados pela mediana relativa de expressão (RME; Relative Median Expression) e expressão diferencial, assim como as vias metabólicas associadas a genes de virulência e metabolismo de açúcares. Dois genes (CaO19.610, FDR=0.009; CaO19.2506, FDR=0.018) apresentaram expressão diferencial significativa em superfície radicular hígida (SRS) e tem suas funções relacionadas a formação de biofilme. Enquanto que em superfície radicular cariada (RC) sete genes (UTP20, FDR=0.018; ITR1, FDR=0.036; DHN6, FDR=0.046; CaO19.7197, FDR=0.046; CaO19.7838, FDR=0.046; STT4, FDR=0.046; GUT1, FDR=0.046) apresentaram expressão diferencial significativa e tem suas funções relacionadas a atividade metabólica, transporte de açúcares, tolerância ao estresse, invasão e regulação de pH. Candida albicans é um microrganismo importante no desenvolvimento da doença cárie radicular. / The microbiota associated with root caries must be acidogenic and aciduric. S. mutans, Lactobacillus, Actinomyces, Veilonella, Bifidobacterium, and other bacteria play important roles in root caries biofilm. Yeasts are also present on carious and non-carious root biofilms, being the specie Candida albicans the most prevalent yeast found in root biofilms. Although the presence of Candida albicans is stablished in the literature, and there are an increasing gradient of Candida species. colonization with caries progression, the role of this microorganism in root caries has not being totally elucidated. The aim of this study is to analyse the role of Candida albicans in root caries thought a transcriptomic analysis of biofilms of sound root surfaces (n=10, SRS) and root caries lesions (n=9, RC) using a high-throughput sequencing of cDNA (RNA-Seq). The differential expression of genes of Candida albicans SC5314, the specific functions and pathways associated with the gene expression of the present study were investigated. The total bacterial RNA was extracted and the mRNA was isolated (Illumina Hi-Seq2500). Samples with low RNA concentration (less than 30ng/RNA) were pooled, yielding a final sample size of SRS=10 and RC=9. Sequence reads were compiled in a count table and mapped to C. albicans SC5314 genome of reference, using the software CLC Genomics Workbench 7.5.1. Gene expression was calculated in the algorithm DESeq, and the differential expression was calculated with binomial negative (Log2FoldChange) and False Discovery Rate (FDR<0,05). The genes with higher expression in RC and SRS were analysed by the Relative Median Expression (RME), and the virulence factors and pathways and sugar metabolization related with Candida albicans pathogenicity in root caries were analysed. Two genes (CaO19.610, FDR=0.009; CaO19.2506, FDR=0.018) are up-regulated in Sound Root Surface (SRS) have their functions related to biofilm formation and seven (UTP20, FDR=0.018; ITR1, FDR=0.036; DHN6, FDR=0.046; CaO19.7197, FDR=0.046; CaO19.7838, FDR=0.046; STT4, FDR=0.046; GUT1, FDR=0.046) are up-regulated in biofilm of carious dentin (RC) have functions related to metabolic activity, sugar transport, stress tolerance, invasion and pH regulation.

O envelhecimento da população tem resultado em mudanças no padrão de doenças, com aumento importante na prevalência de doenças não transmissíveis e problemas de saúde mental, como a depressão, cujos impactos incluem mudanças negativas nos comportamentos em saúde e piora na imunidade. O presente estudo teve como objetivo avaliar a associação entre sintomas depressivos e cárie radicular em idosos vivendo independentemente em Carlos Barbosa, RS. Para tanto, realizou-se um estudo transversal, por meio de amostra aleatória simples, com coleta de dados realizada durante 2004. Todos os idosos não hospitalizados, acamados ou que não residiam em casas de repouso, foram convidados a participar. Entre os que responderam positivamente ao convite, 785 completaram o protocolo (entrevista e exame), dos quais 390 foram incluídos por possuírem pelo menos 1 dente. A estimativa do tamanho amostral indicou a necessidade de uma amostra composta de 404 idosos para avaliar associação entre depressão e cárie. Medidas: inventário padronizado com variáveis sociodemográficas e de comportamentos de saúde, escala reduzida de sintomatologia depressiva (Geriatric Depression Scale) e exame clínico odontológico, com índice CPOD-Raiz, índice de placa visível, além de coleta de saliva para determinação de fluxo estimulado. O desfecho do presente estudo foi à razão existente entre o numero de raízes cariadas e o número de raízes em risco à cárie. A existência de associação entre as variáveis independentes e o desfecho foi verificada por meio de regressão binomial negativa. Aproximadamente metade da população era do sexo masculino (51,3%) e a média de idade foi de 66,87 anos (±6,1). A maioria dos entrevistados era casada (80%), morava na zona urbana (52,7%), ganhavam até 1 salário mínimo (52,3%) e possuía até a 4ª série completa (36,5%). Quanto ao hábito de fumar, 72,5% relatou não fumar, 33% dos entrevistados afirmou escovar os dentes mais do que duas vezes ao dia e a média da quantidade medicamentos ingeridos por dia foi de 1,89 (±1,9). A regressão binomial negativa revelou um modelo final onde idade (β= 0,03) (p=0,001), sexo feminino (β=-0,23) (p=0,08), viver na zona rural (β=025) (p=0,008), freqüência de escovação (β=0,43) (p=0,025), fluxo salivar (β=-0,012) (p< 0,0001), e a interação das variáveis sexo (masculino) e presença de sintomas depressivos (β=-0,99) (p=0,012) foram significativamente associadas à cárie radicular. Os achados demonstram que a interação entre sintomas de depressivos e sexo masculino foi associada ao desfecho cárie radicular, sugerindo que mecanismos psicológicos podem estar envolvidos na etiologia da cárie e idosos. / Aging is leading to changes in the pattern of disease in the population, with an important increase in the prevalence of chronic diseases and mental illnesses, including depression, that have negative impacts in health-related behaviors as well in immunity. The objective of this study was to evaluate the association between depressive symptoms and root caries in independent-living older persons in Southern Brazil. A cross-sectional study using a simple-random sampling was carried out during 2004. Only non-hospitalized, non-bedridden older persons were invited to take part. Amongst those who accepted to take part, 785 completed the study protocol (interview and examination), of which 390 had at least one natural teeth and were considered for statistical analysis purposes. Sample size was estimated to be of 404 participants in order to examine the association between caries and depression. Measures included a standardized questionnaire assessing socio-demographic, health behavior and depression symptoms (Geriatric Depression Scale-Brief version) information. Oral examination included DMFT-Root Index, Visible Plaque Index, and stimulated saliva flow assessment. The studied outcome was the based on the ratio number of decayed roots/number of roots at risk. The existence of association between independent variable and the outcome was assessed using negative binomial regressions. Approximately half of the studied sample was comprised of men (51,3%) and the mean age was 66.87 (±6.1). The majority of the older persons was married (80%), lived in the urban area (52,7%), had a income equivalent to up to 1 Brazilian minimum wage (53.2%), and had up to 4 years of formal education (36.5%). In respect to health behaviors, 72.5% were non or former smokers, 33% reported brushing their teeth at least twice a day and the average of prescription medication intake was 1.89 (1.9). The final, fully adjusted, negative binomial regression model revealed that age (β=0.03, p=0.001), female sex (β=-0.23, p=0.08), living in the rural area (β=0.25, p=0.008), tooth brushing frequency (β=0.43, p=0.025), stimulated saliva flow (β=-0.012, p<0.0001) and the interaction sex(male) and the presence of depression symptoms (β=-0.99, p=0,012) were independent and significantly associated with root caries. The findings showed that the interaction between male sex and depression symptoms was associated with root caries, suggesting that psychological mechanisms may be involved in root caries etiology in older adults.

Thesis (M.S.)--University of Florida, 2004. / Typescript. Title from title page of source document. Document formatted into pages; contains 34 pages. Includes Vita. Includes bibliographical references.

Submitted by Andrea Maselli (deamaselli@yahoo.com.br) on 2018-01-19T20:23:34Z No. of bitstreams: 2 Tese PDF Impressão.pdf: 1825558 bytes, checksum: 52a8a536c671378887d7f638e8244a82 (MD5) Tese PDF Impressão.pdf: 1825558 bytes, checksum: 52a8a536c671378887d7f638e8244a82 (MD5) / Approved for entry into archive by Silvana Alvarez null (silvana@ict.unesp.br) on 2018-01-23T19:31:17Z (GMT) No. of bitstreams: 1 maselli_a_me_sjc.pdf: 1719458 bytes, checksum: 9bbc488c5915b3ba270ef7fd508729ab (MD5) / Made available in DSpace on 2018-01-23T19:31:17Z (GMT). No. of bitstreams: 1 maselli_a_me_sjc.pdf: 1719458 bytes, checksum: 9bbc488c5915b3ba270ef7fd508729ab (MD5) Previous issue date: 2017-12-17 / A mensuração da degradação de colágeno radicular é um importante parâmetro para avaliar a progressão de cáries na dentina ou a eficácia de métodos terapêuticos na prevenção de lesões não cariosas. O objetivo deste trabalho foi avaliar a degradação do colágeno da dentina radicular frente a métodos de prevenção de cárie, utilizando o teste da Hidroxiprolina e a microradiografia. Foram obtidos 40 blocos de dentina radicular com aproximadamente 1,5 mm de profundidade x 6 mm de diâmetro, a partir de incisivos bovinos, os quais foram submetidos ao processo de desmineralização artificial em tampão acetato (pH=5), a fim de induzir a formação de uma lesão cariosa. Em seguida as amostras foram submetidas aos tratamentos preventivos de cárie radicular: 1) Clorexidina 0,12% 1 min, 2) Flúor neutro 2% 1 min, 3) Nd: YAG Laser- 60 mJ 10 s e 4) Água Deionizada (controle) 1 min. Após os tratamentos as amostras foram expostas à degradação pela enzima colagenase (Tipo VII, Produto No. C0773, Sigma-Aldrich, St. Louis, MO, USA) por um período de 5 dias. Ao final do desafio da colagenase, a solução contendo a enzima foi coletada para ser submetida ao teste da hidroxiprolina, para a mensuração da quantidade de colágeno degradado por meio de colorimetria em espectrofotômetro. Em seguida as mesmas amostras foram submetidas à mais 2 dias de desmineralização. Em complemento ao ensaio da hidroxiprolina as amostras foram expostas à microradiografia transversal para visualização e medição da área degradada. Uma análise descritiva dos dados obtidos foi realizada de modo a determinar o teste estatístico a ser aplicado. A análise de variância (ANOVA) para a HYP revelou que não houve diferença estatisticamente significativa entre os tratamentos empregados (p>0,05). Os dados obtidos na microradiografia foram submetidos ao teste de Kruskal Wallis e teste de comparações múltiplas, Dunn. Os dados de reptetição, comparações entre a desmineralização inicial (5 dias) e a segunda desmineralização (2 dias), foi realizado individulamente em cada grupo por teste T de medidas repetidas ou Wilcoxon. Houve diferença significativa entre os grupos (p<0,0001). Dos tratamentos empregados, a clorexidina e o flúor foram eficazes na prevenção da progressão da cárie radicular. / Quantification of collagen degradation is an important parameter to evaluate dentin caries progression of caries prevention aid. The aim of this study was to evaluate root collagen degradation against preventive methods by using the hydroxyproline assay and microradiography technique. Forty root dentin blocks were obtained with 1,5x6 mm (depth x diameter) from bovine incisors, which were submitted to artificial demineralization process by acetate buffer (PH=5), in order to induce a carious lesion. Then, the samples were submitted to preventive therapeutic treatment of root caries: 1) Chlorhexidine 0,12% 1 min, 2) Fluoride 2% 1 min, 3) Nd:YAG Laser - 60 mJ 10s, 4) Deionized Water (control) 1 min. After that, the samples were exposed to degradation by the collagenase enzyme (Type VII, Product No. C0773, Sigma- Aldrich, St. Louis, MO, USA) for 5 days. Following the collagenase challenge, the enzyme solution was collected for assaying hydroxyproline released from collgen matrix, where it is possilble to measure the amount of degraded collagen by colorimetry in a spectrophotometer. Soon after, the same samples were submitted to a further 2 days of demineralization process. In addition to the hydroxyproline assay the samples were exposed to the transverse microradiography for a visualization of the degraded area. Soon after the colorimetric test the same samples were submitted to further two days of demineralization. A descriptive analysis of the data will be performed to determine the statistical test to be applied. ANOVA test revealed that there was no difference between the treatments (p>0,05). The microradiography data were submitted to the Kruskal Wallis test and multiple comparison test, Dunn. The repetition data, comparisons between the initial (5 days) and the second (2 days) demineralization, were performed individually in each group by repeated measures T-test or Wilcoxon (p<0,0001). Among the proposed treatments, chlorhexidine and fluoride were effective in preventing root caries progression.