Thesis (M.A.)--University of Delaware, 2007. / Principal faculty advisor: Brock W. Jobe, Winterthur Program in Early American Culture. Includes bibliographical references.

AIM: The aim of this study is to compare, in a randomized clinical trial, the appearance improvement of white spot carious lesions (WSL) treated with resin infiltration (RI) – ICON®, 5% sodium fluoride (22,600 parts per million (ppm) with fluoride varnish (FV), and to assess the synergistic effect of adding Casein Phosphopeptide-Amorphous Calcium Phosphate- MI Paste® (MIP) to these treatment modalities. METHODS: Forty subjects with unrestored WSL, after debanding fixed orthodontic appliances, were recruited from the Department of Orthodontics, Henry M. Goldman School of Dental Medicine, Boston University. A randomized, split-mouth, and double-blind clinical trial design was used to allocate subjects to resin infiltration and fluoride varnish without MI Paste® (RI and FV), 20 patients, and resin infiltration and fluoride varnish with MI Paste® (RI-MIP and FV-MIP), 20 patients. Patients in the MI Paste® present treatment group given 6-weeks supply of MI Paste®. The assessment methods were: 1) patient self-assessment, 2) expert panel subjective assessment, 3) clinical caries assessment using the International Caries Detection and Assessment System (ICDAS), and 4) actual lesion size assessment. Treatment efficacy was assessed after 4-6 weeks of application. The appearance improvement was analyzed at α level of 5% and a power of 90%. RESULTS: Over 4-6 weeks, RI treatment appeared to have a higher mean difference between baseline and follow-up compared to fluoride varnish with a statistically significant difference across all assessment methods. The patient self-assessment mean difference was 1.07 (±1.49); 95% CI [0.59 - 1.55], the expert panel subjective assessment mean difference was 0.75 (±1.06); 95% CI [0.61 - 0.88], the ICDAS mean difference was 0.38 (± 0.43); 95% CI [0.24 - 0.52], and the actual size assessment mean difference was 0.07 (±0.16); 95% CI [0.01 - 0.12]. There was no statistically significant difference between the mean differences between RI and RI-MIP, nor between FV and FV-MIP across all assessment methods. CONCLUSION: The results indicate that RI is significantly better in improving the appearance of WSLs when compared to FV. There is little evidence that use of MIP adds to the improvement of the appearance of WSL in conjunction with either modality. / 2019-09-26T00:00:00Z

Conservators have long been aware of the problems associated with the preservation of rubber objects due to inherent instability that can be attributed, in part, to the presence of additives. Inorganic additives, such as fillers, accelerators, stabilizers, and special ingredients are necessary in manufacturing to alter the properties of natural rubber. These materials all have different interactions with the rubber, and each other, and differing effects on the ageing process. To date, the most effective and accepted methods to preserve rubber are cold, dark storage of objects, or the use of low oxygen environments. While these methods are effective, they greatly limit access. The application of coatings to the surface of rubber objects can slow deterioration and greatly increase the ability of an institution to handle and display rubber objects. While numerous coatings for preventive and interventive treatment have been tested, none have been so successful to warrant routine use. The first section of this research highlighted the relationship between the inclusion of certain additives in natural rubber objects and the accelerated or slowed down overall degradation. In the second part of this research, the acrylic varnishes Golden Polymer Varnish with UVLS, Lascaux Acrylic Transparent Varnish-UV, Sennelier Matte Lacquer with UV Protection, and Liquitex Soluvar Varnish containing ultraviolet light absorbers or stabilizers were tested as a preventative coating for rubber. Through testing the visual and physical properties of the samples, as well as compound analysis the results of this research suggest that acrylic varnishes do provide protection, each to varying degrees. The results also provided insight into the behavior of rubber and these varnishes with continuing light exposure. / Thesis (Master, Art Conservation) -- Queen's University, 2013-10-04 20:14:54.597

The presented work deals with preparation of test samples filled microparticles of mica and nanoparticles of silicon dioxide (SiO2). Monitors the impact of climatic conditions and filler on electrical properties of composite materials. Electrical properties of composite materials are measured by dielectric relaxation spectroscopy. Test samples influence of epoxide resin TSA 220S and polyester resin DOLPHON XL 2102. Varnishes are modified with different weight percentage of nanoparticles of silicon dioxide, or micronized mica. The results of this project are frequency dependencies of parts of complex permittivity and their evaluation.

Purpose: The purpose of this study is to assess the impact of preventive dental services (screening, oral health education, and fluoride varnish) given by pediatric medical providers with an assessment of caregivers interviewed at baseline and at 6-months follow-up.Methods: Using a prospective cohort study design, an oral health knowledge and socio-demographic questionnaire was delivered to a cross-section of caregivers of preschool-aged children seen at VCU Children's Pavilion. Baseline data was used to conduct a cross-sectional analysis of caregivers prior to their children receiving preventive dental services (screening, oral health education, and fluoride varnish). Subsequently, six months into the program, caregivers of children receiving preventive dental services were retested on their oral health knowledge. The 23-item questionnaire included knowledge, behavior and opinion items on risk factors for dental diseases, care of child's teeth, and socio-demographic characteristics of the family. Data collection occurred in the clinic waiting rooms and the examination rooms. Results: A sample of 120 caregivers completed the baseline questionnaire. Caregivers at baseline reported 89% of the children have never been to a dentist. Sixty-four percent of caregivers have never been told by a doctor or nurse when their child should go to the dentist. After receiving preventive dental care in a primary care setting, there was a significant increase in the use of fluoridated toothpaste and less trouble brushing the child's teeth. Caregivers reported a significant increase in information given to them by medical residents about how to brush the child's teeth.Conclusion: The delivery of preventive dental services in a primary care setting is effective in improving certain aspects of caregiver oral health knowledge, though persistence is needed to further caregiver education in an effort to improve the oral health of children.

Purpose: The purpose of this study is to examine the social determinants of CHIP (Child Health Investment Partnership) of Roanoke Valley children who participated in the preventive oral health program compared to those who did not. Methods: This is a retrospective cohort study of children (n=2,425) enrolled in CHIP of Roanoke Valley from September 2008-September 2014. Bivariate analysis and multivariable logistic regression models were used to compare age, gender, race, locality, parents’ education level, age at enrollment, and length of enrollment for oral health program participants versus those who did not participate. Results: Children who were Hispanic as well as children who enrolled in CHIP at an earlier age were more likely to enroll in the oral health program. Conclusions: By focusing on enrolling children at earlier ages, there is the potential to increase the use of dental care to match the recommended periodicity of dental care for young children.

With the amount of users on the web steadily increasing websites must at times endure heavy loads and risk grinding to a halt beneath the flood of visitors. One solution to this problem is by using HTTP reverse proxy caching, which acts as an intermediate between web application and user. Content from the application is stored and passed on, avoiding the need for the application produce it anew for every request. One popular application designed solely for this task is Varnish; another interesting application for the task is Nginx which is primarily designed as a web server. This thesis compares the performance of the two applications in terms of number of requests served in relation to response time, as well as system load and free memory. With both applications using their default configuration, the experiments find that Nginx performs better in the majority of tests performed. The difference is however very slightly in tests with low request rate.

A discussion of possible means by which the varnish of Master John's portrait of Katherine Parr (c.1545) might be conserved, providing historical context and a description of new conservation methods.

A erupção de molares permanentes é importante para o estabelecimento da doença cárie dentária. Embora a maioria das lesões de cárie oclusal tendem a inativar uma vez que os molares permanentes atingem o plano oclusal, estudos recentes têm mostrado que uma quantidade significativa destas lesões permanecem ativas, necessitando de um tratamento adequado. O objetivo deste estudo foi observar a efetividade do verniz fluoretado (Duraphat, Colgate) e do ionômero de vidro modificado por resina (ClinproXT, 3M) na inativação de lesões em esmalte em molares permanentes em erupção. Este ensaio clínico randomizado paralelo longitudinal foi realizado entre Junho de 2014 e julho de 2015. 64 molares (± 2,37 dentes por crianças) foram tratados (33 selados e 31 tratados com verniz fluoretado), e reavaliados após 3, 6, 9 e 12 meses. 97% das lesões seladas, e 74,2% das lesões que receberam aplicações de verniz fluoretado foram inativadas em um intervalo de 12 meses (p=0,04). A idade das crianças e as intervenções realizadas foram estatisticamente associadas com a paralização das lesões (modelo de regressão deWeibull Cox, p>0,05). Este estudo mostrou que os selantes de ionômero de vidro modificado por resina tiveram um melhor desempenho que aplicações de verniz fluoretado na inativação de lesões em esmalte ativas após um período de acompanhamento de 12 meses. / Background: Eruption of permanent molars is significantly important for the development of dental caries. Although most occlusal caries lesions tend to arrest when teeth reach the occlusal plan, recent studies have shown that an important proportion of these lesions remain active, and in need of proper management. Aim: The aim of this study was to investigate the effectiveness of resin modified glass ionomer cement for pit and fissures sealing (ClinproXT, 3M) and fluoride varnish (Duraphat, Colgate) on arresting enamel carious lesions, on erupting molars in different stages of eruption. Design: This randomized parallel longitudinal clinical study was carried out between June 2014 and June 2015. Results: 27 children and 64 molars (±2.37 teeth per children) were treated (33 sealed and 31 treated with fluoride varnish) and reassessed after 3, 6, 9 and 12 months. 97% of the lesions that were treated with ionomer cement sealant were arrested against 74.2% of the lesions that received fluoride varnish applications (p=0.04). Also, children’s age and treatment were significantly associated with occlusal lesion arrestment (Weibull Cox regression models, p>0.05). Conclusions: Resin modified glass ionomer cement sealants performed better than fluoride varnish applications on caries arrestment after a 12-month follow-up period.

A erupção de molares permanentes é importante para o estabelecimento da doença cárie dentária. Embora a maioria das lesões de cárie oclusal tendem a inativar uma vez que os molares permanentes atingem o plano oclusal, estudos recentes têm mostrado que uma quantidade significativa destas lesões permanecem ativas, necessitando de um tratamento adequado. O objetivo deste estudo foi observar a efetividade do verniz fluoretado (Duraphat, Colgate) e do ionômero de vidro modificado por resina (ClinproXT, 3M) na inativação de lesões em esmalte em molares permanentes em erupção. Este ensaio clínico randomizado paralelo longitudinal foi realizado entre Junho de 2014 e julho de 2015. 64 molares (± 2,37 dentes por crianças) foram tratados (33 selados e 31 tratados com verniz fluoretado), e reavaliados após 3, 6, 9 e 12 meses. 97% das lesões seladas, e 74,2% das lesões que receberam aplicações de verniz fluoretado foram inativadas em um intervalo de 12 meses (p=0,04). A idade das crianças e as intervenções realizadas foram estatisticamente associadas com a paralização das lesões (modelo de regressão deWeibull Cox, p>0,05). Este estudo mostrou que os selantes de ionômero de vidro modificado por resina tiveram um melhor desempenho que aplicações de verniz fluoretado na inativação de lesões em esmalte ativas após um período de acompanhamento de 12 meses. / Background: Eruption of permanent molars is significantly important for the development of dental caries. Although most occlusal caries lesions tend to arrest when teeth reach the occlusal plan, recent studies have shown that an important proportion of these lesions remain active, and in need of proper management. Aim: The aim of this study was to investigate the effectiveness of resin modified glass ionomer cement for pit and fissures sealing (ClinproXT, 3M) and fluoride varnish (Duraphat, Colgate) on arresting enamel carious lesions, on erupting molars in different stages of eruption. Design: This randomized parallel longitudinal clinical study was carried out between June 2014 and June 2015. Results: 27 children and 64 molars (±2.37 teeth per children) were treated (33 sealed and 31 treated with fluoride varnish) and reassessed after 3, 6, 9 and 12 months. 97% of the lesions that were treated with ionomer cement sealant were arrested against 74.2% of the lesions that received fluoride varnish applications (p=0.04). Also, children’s age and treatment were significantly associated with occlusal lesion arrestment (Weibull Cox regression models, p>0.05). Conclusions: Resin modified glass ionomer cement sealants performed better than fluoride varnish applications on caries arrestment after a 12-month follow-up period.