Orientador: Fábio Luiz Mialhe / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-22T04:12:08Z (GMT). No. of bitstreams: 1 Silva_CristianeMariadaCosta_D.pdf: 3248704 bytes, checksum: 118fb2ffe038d5896f2acf9514c230e7 (MD5) Previous issue date: 2012 / Resumo: O resumo poderá ser visualizado no texto completo da tese digital / Abstract: The abstract is available with the full electronic document / Doutorado / Saude Coletiva / Doutora em Odontologia

Orientador: Jaime Aparecido Cury / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Odontologia de Piracicaba / Made available in DSpace on 2018-08-26T12:48:18Z (GMT). No. of bitstreams: 1 Fernandez_ConstanzaEstefany_D.pdf: 2276340 bytes, checksum: 1735521ece2fdcfcf30384ce9aabe6df (MD5) Previous issue date: 2015 / Resumo: Dentifrício fluoretado (DF) de concentração convencional (1000-1500-ppm) é eficiente no controle da cárie de esmalte, entretanto seu efeito na cárie radicular pode não ser o mesmo devido à maior susceptibilidade da dentina à cárie. Essa diferença poderia ser compensada pelo uso diário de DF de maior concentração (DF-5000-ppm) ou da combinação da aplicação profissional de fluoreto (APF) com uso diário de DF-1100-ppm. Entretanto, além dessa comparação nunca ter sido pesquisada, a diferença do efeito entre esmalte e dentina tem sido pouco estudada num único experimento. Em acréscimo, o efeito de DF-5000-ppm na dentina radicular se limita a estudos do efeito da remineralização. O Capítulo 1 dessa tese descreve a validação do modelo de biofilme de Streptococcus mutans (SM) para estudar o efeito dose resposta de DF na redução da desmineralização (des-) do esmalte e dentina radicular. No Capítulo 2, foi avaliado in situ o efeito dose-resposta de DF e o efeito de DF-5000-ppm ou a combinação de APF com DF-1100-ppm na redução da des- e ativação da remineralização do esmalte e dentina radicular. No capítulo 1, biofilmes de SM foram crescidos sobre blocos de esmalte e dentina radicular, os quais foram expostos à sacarose 8x/dia e 2x/dia às soluções fluoretadas contendo 0, 150, 450 e 1350-ppm. Ao final do experimento, a concentração de F foi determinada nos biofilmes e nos blocos a dureza de superfície (DS) e F-solúvel em ácido (FAp). No capítulo 2, num desenho cruzado, duplo-cego de 4 fases de 14 dias cada, 18 sujeitos utilizaram dispositivo palatino contendo blocos hígidos e cariados de esmalte e de dentina radicular. Biofilme foi permitido ser acumulado sobre os blocos, os quais foram expostos à sacarose 8x/dia ou 3x/dia, nos blocos hígidos ou cariados, respectivamente. Os tratamentos foram: 1) Dentifrício-placebo (DP); 2) DF-1100; 3) DF-5000; 4) único pré-tratamento dos blocos com APF (gel acidulado, 12300-ppm) combinado com DF-1100 (APF+DF-1100). Dentifrícios foram usados 2x/dia. No fluido e porção sólida do biofilme foram determinadas as concentrações de F. Nos blocos a porcentagem de perda (%PDS) ou recuperação da DS (%RDS), nos substratos hígidos e cariados respectivamente, como também as áreas de lesão de cárie (?S). F-solúvel em álcali e ácido também foram determinadas nos blocos. Os resultados in vitro mostraram que o modelo apresentou efeito dose-resposta, havendo em função da concentração de F um aumento de F no biofilme e um aumento da concentração de FAp e decréscimo da %PDS nos blocos de esmalte-dentina. O efeito do F na redução da desmineralização no estudo in vitro foi menor na dentina do que o observado no esmalte. Os dados in situ mostraram efeito dose-resposta para a concentração de F nos dentifrícios (0;1100;5000) para a maioria das variáveis analisadas, à exceção do ?S para dentina-cariada. Na comparação dos tratamentos, APF+DF-1100 foi estatisticamente mais eficaz que DF-5000 reduzindo desmineralização e ativando a remineralização da dentina radicular. Os resultados dessa tese sugerem que o efeito de DF no controle de cárie de esmalte ou dentina é concentração dependente, sendo a combinação com APF mais relevante para dentina-radicular que para esmalte / Abstract: Fluoride dentifrice (FD) of conventional concentration (1,000-5,000 ppm) is efficient for enamel caries control; however, it is possible that their effect might not be the same for root-caries because dentine is more caries susceptible. This difference could be compensated by the daily use of high concentration FD (5,000 ppm-FD) or by the combination of professional fluoride application with daily use of 1,100 ppm-FD. Besides, this comparison has never been researched; the difference of effect between enamel and dentine has been scarcely evaluated in the same experiment. In addition, the effect of 5,000-FD has been focused essentially on root-caries remineralization. Chapter 1 of this thesis describes the validation of a Streptococcus mutans (SM) biofilm model to study the dose-response effect of FD in the reduction of demineralization (de-) on enamel and root-dentine. In Chapter 2, it was evaluated in situ the FD dose-response effect and the effect of FD-5000 ppm or the combination of acidulated phosphate fluoride (APF) application with DF-1100 ppm in the reduction of de- and activation of remineralization on enamel and root-dentine. In chapter 1, SM biofilms were grown on enamel and root-dentine slabs, and exposed 8x/day to sucrose and 2x/day to fluoridated solutions containing 0, 150, 450 and 13,50-ppm. At the end of the experiment, F-concentration in the biofilms was determined and surface hardness (SH) and acid-soluble-F (FAp) were assessed in the slabs. In chapter 2, in a cross-over and blind design of 4 phases of 14 days each, 18 subjects wore a palatine appliance containing sound and carious slabs of enamel and root-dentine. Biofilm was allowed to accumulate on the slabs and while the sound slabs were exposed to sucrose 8x/day the carious were exposed 3x/day. The treatment groups were: 1) F-placebo dentifrice (PD); 2)1,100-FD; 3) 5,000-FD; 4) slabs pre-treated with APF (F-gel, 12,300 ppm-F) combined with daily use of 1100-FD (APF+1,100-FD). Dentifrices were used 2x/day. The F concentration was determined in fluid and solid portions of the biofilm. In slabs, the percentage of SH loss (%SHL) or recovery (%RSH) was estimated in sound and carious slabs, respectively, as well as the caries lesion area (?S). Acid-soluble-F and alkali-soluble-F concentrations were also determined in the slabs. The in vitro results showed that the model presented a dose-response effect, with an increment of F concentration in the biofilm and an increment of FAp in function of F concentration of the treatments. Also, %SHL showed a reduction in enamel and dentine slabs according to the treatments. F effect on the reduction of demineralization was lower on dentine than that observed on enamel. The in situ data showed a dose-response effect to F concentration in the dentifrices (0;1,100;5,000) for most response variables, with the exception of ?S for carious-dentine. In the treatments comparison, APF+1100-FD was statistically more effective than 5000-FD at reducing demineralization and activating remineralization in root-dentine. The results from this thesis suggest that the FD effect in enamel and dentine caries control is concentration-dependent, and the combination with APF was more relevant to root-dentine that to enamel / Doutorado / Cariologia / Doutora em Odontologia

A thesis submitted to the College of Dental Medicine of Nova Southeastern University of the degree of Master of Science in Dentistry. Objective: This study was conducted to determine the resistance to wear and effectiveness of Opal®Seal (Opal Orthodontics by Ultradent, South Jordan, UT, USA) against enamel demineralization in comparison to L.E.D. Pro Seal® (Reliance Orthodontic Products, Itasca, IL, USA). Background: Development of white spot lesions (WSL) is a primary concern during fixed orthodontic treatment. With poor oral hygiene during orthodontic therapy, it is almost inevitable that enamel demineralization will occur and WSLs will be seen clinically. Numerous materials have demonstrated successful prevention of WSLs, including topical varnishes and sealants, gels, pastes and bonding agents. The newly developed sealant Opal Seal is claimed by the manufacturer to prevent demineralization and subsequent WSLs from forming during orthodontic treatment. To evaluate the effectiveness of Opal Seal, we tested and compared it to Pro Seal, which has proven to be successful at WSL prevention and is, like Opal Seal, a fluoride-releasing, light-cured, low viscosity filled resin sealant. Methods: A total of 48 non-carious extracted human premolar teeth were divided into 3 groups representing one of the following topical treatments: no treatment (C), Opal Seal (OS) or L.E.D. Pro Seal (PS). Each group was subdivided into either T1 or T2 time interval groups (C1, C2, OS1, OS2, PS1 and PS2) and teeth were subjected to 10,000 or 20,000 simulated brush strokes, respectively, followed by exposure to an acidic solution for 96 hours. Teeth were examined macroscopically for product wear and assessment of WSL development and then sectioned for quantitative examination with polarized light microscopy. Results: Visual assessment revealed wear of L.E.D. Pro Seal in 62.5% of the PS2 teeth following exposure to toothbrush abrasion and acidic challenge. No L.E.D. Pro Seal or Opal Seal wear was found in any PS1 or OS teeth, respectively. WSLs involving 50-100% of the exposed enamel surface developed in all control teeth and 37.5% of PS teeth had WSLs involving less than 50% of their enamel surface. These WSLs were visible as small, white, isolated points. No visible WSLs were found in any teeth in the OS group. A Fisher's Exact test was used to evaluate any differences in demineralization within groups over time. The results indicate a significant difference in the number of lesions found at T1 compared to T2 in the PS group (p = 0.003). A non-parametric Kruskal-Wallis test using a Wilcoxon test for all multiple comparisons was conducted to evaluate any differences among the treatment groups for change in depth of demineralization (µm) at two different time points. PS and OS groups were found to have significant differences in average lesion depth compared to the control groups at T1 and T2 (pConclusions: Our results showed that both Opal Seal and L.E.D. Pro Seal reduce enamel demineralization when teeth are subjected to simulated toothbrush abrasion and an acidic environment over time. Opal Seal provided superior protection of the enamel surface and demonstrated complete wear resistance and prevention of demineralized lesion development in our experimental groups.

Indiana University-Purdue University Indianapolis (IUPUI) / Erosive tooth wear (ETW) is an emerging dental condition manifested clinically as tooth surface loss, eventually impairing the teeth’s structural integrity, function, and esthetics. Both research and practice are in need of a quantitative, non-destructive method to monitor ETW. Cross-polarization optical coherence tomography (CP-OCT), an advanced imaging tool, shows great potential to fulfill this need, but its feasibility and shortcomings remain unclear. In this dissertation, I explored the capability of CP-OCT to monitor ETW in three in vitro studies, one per chapter. Chapter 2 investigated the effects of enamel surface roughness and dental erosion severity on CP-OCT dental surface loss measurements. Chapter 3 tested the effects of enamel surface roughness and dental erosion on CP-OCT enamel thickness measurements at different simulated wear levels. Chapter 4 explored the ability of CP-OCT to quantify the thickness of natural and wornout enamel surfaces and to estimate longitudinally the wear depths resulting from simulated wear. I concluded: (1) enamel surface roughness did not affect CP-OCT measurements of enamel surface loss, however, the estimated error limited the appropriate assessment of the initial stages of dental erosion surface loss using CP-OCT; (2) enamel surface roughness and dental erosion did not affect CP-OCT enamel thickness measurements, and the CP-OCT differentiated the simulated enamel wear levels; and (3) CP-OCT quantified thickness of natural enamel before, during, and after the tooth wear simulation and allowed wear depth estimation following the simulated wear. / 2021-07-03

Direct carbon fuel cell (DCFC) is a high temperature fuel cell (around 700 "C) that produces electrical energy from the direct conversion of the chemical energy of carbon. DCFC has a higher achievable efficiency of 80% compared to other fuel cells and the corresponding CO2 emission is very low compared to conventional coal-burning power plants. Moreover, a DCFC can use diversified fuel resources even waste material, which is advantageous compared to other types of fuel cells which are limited to specific fuels. DCFCs are still under development due to a number of fundamental and technological challenges such as the efficiency of carbon fuels and the effect of impurities on the performance and lifetime of the DCFC. These are key factors for the development and commercialization of these devices. In this study, three biochars obtained from the pyrolysis of poultry litters (PL) collected from Tunisian and US farmers, were characterized to see whether they can be potential anode fuels for DCFC or not. PL biochars have low fixed carbon contents (19-35 wt%) and high ash contents (32.5-63 wt%). These ashes contain around 40 wt% catalytic oxides for carbon oxidation reaction, however, these oxides have very low electrical conductivities, which resulted in the very low (negligible) electrical conductivity of the PL biochars (7.7x10-9-70.56x10-9 S/cm) at room temperature. Moreover, the high ash contents resulted in low surface areas (3.34-4.2 m"/g). These findings disqualified PL biochar from being a potential anode fuel for DCFCs. Chemical demineralization in the sequence HF/HCl followed by carbonization at 950" C of the PL biochars will result in higher fixed carbon content, higher surface area, and higher electrical conductivities. Moreover, the treated PL biochars would contain a potential catalyst (Calcium in the form of CaF2) for carbon oxidation. All these criteria would qualify the treated PL biochars to be potential fuels for DCFC. / Master of Science

A erosão dentária ocasiona a perda da estrutura dental através da dissolução da sua porção mineralizada por ácidos de origem não bacteriana. Assim, o objetivo deste estudo é avaliar a capacidade de materiais contendo compostos bioativos de remineralizar o esmalte bovino submetido a desafio erosivo e se o método de quantificação da fluorescência induzida por luz (QLF) tem correlação com os resultados do teste de microdureza Knoop. 120 fragmentos de esmalte bovino foram distribuídos entre os grupos experimentais, sendo n=5 para o teste de microdureza (3 x 3 x 2 mm) e n=10 para o método do QLFTM (5 x 5 x 3 mm). Os corpos-de-prova foram analisados em três momentos diferentes (inicial, após 2 dias de protocolo de erosão e após 6 dias de tratamento remineralizador). As amostras foram submetidas a 2 dias de protocolo de erosão, através de imersão em ácido cítrico a 0,3% pH 3,2, por 2 minutos e manutenção das mesmas em saliva artificial (pH 7,0) durante 24 horas. Na sequência, foram realizados os tratamentos remineralizadores por 6 dias consecutivos: 1 gota de saliva foi depositada sobre as amostras e após 1 hora foram imersas por 2 minutos em suspensão aquosa preparada com os seguintes materiais: G1-Pro-Argin+NaMFP, bicarbonato de arginina + carbonato de cálcio + monofluorfosfato de sódio (Colgate® Sensitive Pró-Alívio); G2-Recaldent+NaF, fosfopeptídeo de caseína com fosfato de cálcio amorfo + fluoreto de sódio (MI Paste Plus); G3-ACP+NaF, fosfato de cálcio amorfo + fluoreto de sódio + nitrato de potássio (Relief ACP); G4-CaGP+KF, glicerofosfato de cálcio + fluoreto de potássio (Flúor Protector Gel); G5-NovaMin®+NaF, fosfosilicato de cálcio e sódio + fluoreto de sódio (Nupro® Sensodyne®); G6-NovaMin®+NaMFP, fosfosilicato de cálcio e sódio + monofluorfosfato de sódio (Sensodyne® Repair&Protect); G7-NaF, fluoreto de sódio + nitrato de potássio (Sensodyne® Cool Gel) e G8-saliva artificial (controle negativo). Após 2 horas de imersão em saliva foi repetido o protocolo de erosão. Foram realizadas análises estatísticas para o teste de microdureza e QLF (=0,05). A ANOVA de dois fatores para medidas repetidas mostrou diferenças estatisticamente significativas apenas para os momentos da análise e para a interação dos fatores tratamentos x momentos da análise. O teste de Tukey mostrou diferenças significativas na comparação entre todos os momentos da análise e na interação momentos da análise x tratamentos: valores iniciais x após erosão e após tratamento e entre os valores após erosão x após tratamento (NovaMin®+NaF, NovaMin®+NaMFP, NaF e saliva). O teste de Tukey na comparação dos tratamentos no momento final da análise mostrou diferenças significativas na análise da microdureza para o Recaldent+NaF x NovaMin®+NaF, NovaMin®+NaMFP e NaF; mas no QLF, as diferenças ocorreram entre o Pro-Argin+NaMFP x NaF e saliva; Recaldent+NaF x NovaMin®+NaMFP, NaF e saliva e ACP+NaF x NaF. Nenhum dos tratamentos foi capaz de remineralizar totalmente o esmalte dental, mas os materiais Pro-Argin+NaMFP, Recaldent+NaF, ACP+NaF e CaGP+KF foram capazes de estabilizar o processo de erosão do esmalte com resultado superior aos demais tratamentos. O método do QLF mostrou uma correlação positiva significativa com os resultados do teste de microdureza. / Dental erosion leads to loss of the tooth structure by dissolving its mineral portion by acids for non-bacterial origin. The objective of this study is evaluate the ability of materials with bioactive compounds to remineralize bovine enamel subjected to erosive challenge and verify the possible correlation between the datas from the quantitative light-induced fluorescence method (QLF) and the Knoop surface microhardness test. 120 bovine enamel pieces were distributed among experimental groups with n=5 for microhardness testing (3 x 3 x 2 mm) and n=10 for the QLF method (5 x 5 x 3 mm) and were analysed at three different times (initial, after 2 days of erosion protocol and after 6 remineralizing days of treatment).The samples were subjected to two-days erosion protocol, through its immersion into 0,3% citric acid solution pH 3,2 for 2 minutes and maintaining them into artificial saliva for 24 hours (pH 7,0). Following remineralizing treatments were performed for 6 consecutive days: the samples were covered with 1 drop of saliva and after 1 hour were immersed for 2 minutes in the slurry prepared with the following materials: G1-Pro-Argin+NaMFP, arginine bicarbonate + calcium carbonate + sodium monofluorophosphate (Colgate® Sensitive Pro-Alívio); G2-Recaldent+NaF, casein phosphopeptide-amorphous calcium phosphate + sodium fluoride (MI Paste Plus); G3-ACP+NaF, amorphous calcium phosphate + sodium fluoride + potassium nitrate (Relief ACP); G4-CaGP+KF, calcium glycerophosphate + potassium fluoride (Fluor Protector Gel); G5- NovaMin®+NaF, calcium sodium phosphosilicate + sodium fluoride (Nupro® Sensodyne®); G6-NovaMin®+NaMFP, calcium sodium phosphosilicate + sodium monofluorophosphate (Sensodyne® Repair&Protect); G7-NaF, sodium fluoride + potassium nitrate (Sensodyne® Cool Gel) and G8-Artificial saliva (negative control). After 2 hours of soaking in saliva the erosion protocol was repeated. Statistical analyzes were conducted for microhardness and QLF with coincidence of the results (=0,05). A two-factors ANOVA for repeated measures showed statistically significant differences only for the time of analysis and the interaction treatments x time of analysis. The Tukey test showed statistically significant differences when comparing the three times of analysis and the interaction between times of analysis x treatments: baseline values with values after erosion and after treatment and the values after erosion x after treatment (NovaMin®+NaF, NovaMin®+NaMFP, NaF and saliva). The Tukey test when comparing the treatments x final times of analysis showed statistically significant differences in microhardness test for Recaldent+NaF x NovaMin®+NaF, NovaMin®+NaMFP and NaF; in QLF method the differences occurs between Pro-Argin+NaMFP x NaF and saliva; Recaldent+NaF x NovaMin®+NaMFP, NaF and saliva; ACP+NaF x NaF. None of the treatments was able to completely remineralize bovine enamel, but Pro-Argin+NaMFP, Recaldent+NaF, ACP+NaF and CaGP+KF materials were able to stabilize the eroding enamel, thus demonstrating a score higher than others and the QLF method showed a significant and positive correlation with the microhardness test results.

Objetivou-se realizar um estudo retrospectivo sobre a frequência de cães acometidos pela reabsorção dentária (RD) atendidos no Laboratório de Odontologia Comparada da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, no período de 2006 a 2017, correlacionando com características como raça, idade, sexo, doenças orais concomitantes, hábito alimentar, comportamento mastigatório, histórico dental e sinais clínicos relacionados a dor, bem como, relatar estatisticamente os grupos dentários frequentemente acometidos, porções dentárias mais afetadas, aspectos radiográficos e extensão da reabsorção de acordo com a classificação determinada pelo American Veterinary Dental College (AVDC). Os dados avaliados procederam de 2.364 prontuários contendo fichas de consulta e de tratamento, além da análise de 1.122 registros radiográficos. Constatou-se que a prevalência geral da RD em cães foi de 8,7% e o ano mais frequente foi 2016 com 21,2%. Os pré-molares mandibulares e os maxilares foram significativamente mais afetados (37,3% e 38,1% respectivamente) e a porção radicular apresentou-se mais acometida (60,5%). As lesões do tipo 1 foram significativamente mais frequentes (53,2%) que as lesões do tipo 2 (27,9%) e tipo 3 (8,1%). Não houve lesões classificadas no estágio 1. Os estágios da reabsorção dentária mais frequentes foram o RD3 com 34,3% e o RD2 com 29,5%. Os estágios 4a, 4b e 4c representaram respectivamente 3,3%, 1,8% e 12,8%. No estágio 5, detectou-se apenas fragmentos de raiz em estágio avançado da reabsorção (2,3%). A reabsorção dentária foi associada estatisticamente com os cães de idades avançadas (10 e 13 anos com 14,6% cada). Não houve diferença significativa entre a frequência de machos e fêmeas, mas, a frequência de cães castrados (42,3%) foi significativamente menor do que a de não castrados (57,7%). A doença periodontal mostrou-se significativamente associada à reabsorção dentária (84,0%), seguida das fraturas dentárias (20,9%). Os cães acometidos pela RD alimentavam-se somente de ração (90,5%), premium ou super premium (86,6%). A maioria dos cães apresentaram-se assintomáticos no pré-operatório (82,0%) e sem alteração do comportamento no pós-operatório (39,3%). O tratamento de escolha para 66,5% dos casos foi a extração dentária. Concluiu-se que: a reabsorção inflamatória externa ou reabsorção do tipo 1, mostrou-se mais frequente quando comparada com a reabsorção de substituição externa (tipo 2). Sugere-se que boa parte da reabsorção dentária dos cães avaliados nesse estudo, esteja diretamente relacionada com processos inflamatórios desencadeados pela doença periodontal, uma vez que, evidenciou-se correlação estatística significativa entre a reabsorção dentária e a doença periodontal. / The objective of this study was to conduct a retrospective study on the frequency of dogs affected by tooth resorption attended at the Laboratory of Comparative Dentistry of the Faculty of Veterinary Medicine and Animal Science of the University of São Paulo from 2016 to 2017, correlating with characteristics such as race, age, sex, concomitant oral diseases, eating habits, masticatory behavior, dental history and clinical signs related to pain, as well as, statistically reporting the frequently affected dental groups, most affected dental portions, radiographic aspects and extent of resorption according to the classification determined by the American Veterinary Dental College (AVDC). The data evaluated came from 2,364 medical records containing records of consultation and treatment, in addition to the analysis of 1,122 radiographic records. It was found that the overall prevalence of tooth resorption in dogs was 8.7% and the most frequent year was 2016 with 21.2%. The mandibular and maxillary premolars were significantly more affected (37.3% and 38.1%, respectively) as well as the root portion (60.5%). Type 1 lesions were significantly more frequent (53.2%) than type 2 (27.9%) and type 3 (8.1%) lesions. There were no lesions classified in stage 1. The most frequent stages of tooth resorption were E3 with 34.3% and E2 with 29.5%. Stages 4a, 4b and 4c represented 3.3%, 1.8% and 12.8%, respectively. In stage 5, only root fragments were detected at an advanced stage of reabsorption (2.3%). Dental resorption was statistically associated with dogs at advanced ages (10 and 13 years old with 14.6% each). There was no significant difference between the frequency of males and females, but the frequency of castrated dogs (42.3%) was significantly lower than that of non-castrated dogs (57.7%). Periodontal disease was significantly associated with tooth resorption (84.0%), followed by dental fractures (20.9%). The dogs affected by tooth resorption were only fed commercial food (90.5%), premium or super premium (86.6%). Most of the dogs were asymptomatic in the preoperative period (82.0%) and no change in postoperative behavior (39.3%). The treatment of choice for 66.5% of the cases was dental extraction. It was concluded that: The external inflammatory resorption or type 1, was more frequent when compared to external replacement resorption (type 2). It is suggested that a good part of the dental resorption of the dogs evaluated in this study is directly related to inflammatory processes triggered by periodontal disease, since a significant statistical correlation between dental resorption and periodontal disease was evidenced.

Este estudo teve como objetivo avaliar do efeito da aplicação tópica de um verniz e solução experimental de TiF4, comparando-os ao verniz e solução de NaF, sobre o processo de des-remineralização do esmalte dentário in situ. Para tal, 132 blocos de esmalte bovino (4x4mm) foram selecionados pela microdureza de superfície, sendo que em metade deles foi produzida lesão de cárie artificial em solução desmineralizante (pH 5,0, 6 dias). Na seqüência, foi determinada a microdureza de superfície pós-lesão. A outra metade dos blocos permaneceu hígida. Onze voluntários participaram de 3 fases cruzadas (14 dias cada, washout de 7 dias), boca-dividida e cegas, nas quais utilizaram aparelhos palatinos com 4 amostras de esmalte por fase (2 hígidas e 2 desmineralizadas), sendo que cada tipo de amostra recebeu um tipo de tratamento (verniz ou solução). Em todas as amostras permitiu-se o acúmulo de placa dentária. Em uma fase (Fase A), foram aplicados agentes a base de NaF a 5,42% (2,45% F- e pH 5,0), em outra fase (Fase B), foram utilizados agentes a base de TiF4 a 4% (2,45% F- e pH 1,0), e na última fase (Fase C) foram utilizados agentes placebos (verniz sem flúor pH 5,0 e sem tratamento). Os tratamentos foram realizados in vitro (verniz-6 h e solução-1 minuto). Durante o período in situ, os voluntários aplicaram solução de sacarose a 20%, 8x5min ao dia, sobre os blocos hígidos, para provocar a desmineralização. Já para os blocos desmineralizados nenhum procedimento foi realizado, para permitir a remineralização. A microdureza de superfície final foi realizada, para o cálculo da porcentagem de variação de microdureza de superfície, assim como a microdureza longitudinal e microradiografia transversal, para o cálculo das perdas de microdureza e volume mineral integradas, respectivamente. Os dados foram submetidos à ANOVA-RM/ Tukey-Kramer, teste t pareado e ANOVA a dois critérios/Bonferroni (p<0,05). Houve uma redução significativa da desmineralização superficial e um aumento significativo da remineralização superficial do esmalte in situ pelos tratamentos com verniz e solução de TiF4, em comparação aos controles. Pôde-se constatar ainda que os tratamentos com o verniz de NaF, verniz de TiF4 e solução de TiF4 foram efetivos na redução da desmineralização subsuperficial in situ. No entanto, observou-se que o protocolo experimental não permitiu uma adequada remineralização de subsuperfície in situ. Com base nos resultados, pode-se concluir que o verniz e a solução de TiF4 parecem ser promissores na prevenção da desmineralização, porém em relação à remineralização mais estudos in situ são necessários. / The aim of this study was to evaluate the effect of the experimental TiF4 varnish and solution, comparing with NaF solution and varnish, on dental enamel de-remineralization in situ. For that, 132 bovine enamel samples (4x4 mm) were selected using surface microhardness, and half of them were submitted to artificial caries lesion formation using a demineralizing solution (pH 5.0, 6 days). The surface microhardness after the demineralization was measured. The other half of the samples remained sound. Eleven volunteers took part in this cross-over, split-mouth and double-blind study performed in 3 phases of each 14 days (washout of 7 days). Four enamel samples were worn in palatal appliances (2 sound and 2 demineralized), being each type of sample submitted to one treatment (varnish or solution). The dental plaque accumulation was allowed on all samples. In phase A, 5.42% NaF varnish/solution was applied (2.45% F-, pH 5.0); in phase B, 4% TiF4 varnish/solution was used (2.45% F-, pH 1.0) and at the last phase (phase C) the placebo treatments were performed (placebo varnish pH 5.0 and no-treatment). The treatments were performed in vitro (varnish-6h and solution-1min). During the in situ phase, the volunteers dripped a solution containing 20% weight/volume (w/v) sucrose on the sound samples for 5 min, 8 times a day, to provoke demineralization. While on the demineralized samples nothing was done, in order to allow remineralization. The final surface microhardness was analyzed for the calculation of the % of surface microhardness change, as well as the cross-sectional hardness and the transversal microradiography, for the calculation of the integrated loss of microhardness and mineral volume, respectively. The data were submitted to RM-ANOVA/ Tukey-Kramer, t test and 2-way ANOVA/ Bonferroni (p<0.05). There was a significant reduction of the surface enamel demineralization and increase of surface remineralization by the treatments with TiF4 varnish and solution compared to control in situ. The treatments with NaF varnish, TiF4 varnish and solution were able to reduce the subsurface demineralization in situ. However, the experimental protocol did not allow the subsurface remineralization in situ. Based on the results, it can be concluded that the TiF4 varnish and solution seem to be promising products for preventing demineralization, but for the remineralization more studies need to be conducted.

Este estudo teve o objetivo de comparar os efeitos da biomodificação radicular por ácido cítrico associado à tetraciclina (AC) ou terapia fotodinâmica antimicrobiana (aPDT) no recobrimento de recessões gengivais pela técnica do enxerto de tecido conjuntivo subepitelial (ETCS). Para o estudo paralelo foram selecionados 60 sítios em 17 pacientes com recessões de classe I e II de Miller de 2 a 5 mm, múltiplas e isoladas, as quais foram divididas em 3 grupos: grupo controle (C) - apenas raspagem, grupo AC raspagem e, aplicação de gel de ácido cítrico associado à tetraciclina (90s) e o grupo aPDT - raspagem e aplicação da terapia fotodinâmica antimicrobiana (Azul de toluidina O 100g/ml + laser vermelho). Os parâmetros clínicos profundidade de sondagem (PS), nível clínico de inserção (NCI), altura da recessão (AR), largura mucosa ceratinizada (LMC), espessura de mucosa ceratinizada (EMC), índice de sangramento à sondagem (ISS), índice de placa (IPI) e porcentagem de recobrimento radicular (%REC) foram avaliados por um examinador cego e calibrado no baseline e 3, 6 e 12 meses de pós-operatório. Avaliou-se a hiperestesia dentinária (HIPER) e a percepção estética (EST) do paciente através de escala analógica visual no baseline e após 7 e 14 dias e 1, 3, 6 e 12 meses. A análise estatística dos dados de NCI foi feita pelo teste ANOVA complementado por Tukey. O teste de Friedman complementado por Wilcoxon foi aplicado para análise intra-grupos. O teste de Kruskal-Wallis foi aplicado para as diferenças entre os grupos, complementado por comparações múltiplas entre os três grupos. Para a %REC foi realizado o teste de Kruskal-Wallis complementado por Dunnet (p<0,05). Observou-se ganho do NCI em todos os grupos, mas este ganho foi maior para os grupos AC (0,55±1,68) e aPDT (0,80±2,11) em relação ao C (2,50±1,99) (p<0,05). Houve redução na AR em todos os grupos, porém o grupo AC (0,40±0,62) teve maior redução quando comparado C (1,15±1,04) (p<0,05). Houve aumento na LMC em todos os grupos e aumento na EMC também em todos os grupos, sendo que a EMC nos grupos aPDT (2,80±0,733) e AC (2,33±0,60) foram iguais com melhores resultados que o C (1,99±0,65) (p<0,05). Para a PS não foram observadas diferenças significantes entre os grupos e nem entre os períodos (p>0,05). A %REC foi maior nos grupos AC (82%±30%) e aPDT (82%±28%) do que no grupo C (58%±40%) (p<0,05). De maneira geral C, AC e aPDT foram semelhantes entre si e entre eles ao longo do tempo para o ISS e IPI (p>0,05). Houve redução significante da HIPER ao longo do tempo e entre os grupos, sendo que em AC (1,20±2,23) e aPDT (0,70±1,15) a diminuição da sensibilidade foi maior do que em C (2,63±2,22) (p<0,05). Houve melhora na EST ao longo do tempo e para o grupo AC (9,40±0,96) foi maior do que o C (8,58±1,07) (p<0,05), sendo que o grupo aPDT foi igual ao C. Concluiu-se que o uso de biomodificadores radiculares, como o AC e aPDT favorecem o recobrimento de recessões, resultando em redução da hipersensibilidade dentinária, maior porcentagem de recobrimento radicular e mais sítios com recobrimento completo, mantendo os resultados a longo prazo. / The aim of this study was to compare root biomodification by a combination of citric acid with tetracycline (CA) or antimicrobial photodynamic therapy (aPDT) on root coverage by subepithelial connective tissue graft (SCTG). Sixty sites with Millers class I or II recessions were divided in three groups: Control (C) scaling only, CA scaling and root conditioning with a combination of citric acid and tetracycline (gel 90s), aPDT scaling and antimicrobial photodynamic therapy (toluidine blue O 100 g/ml and red laser). Periodontal clinical parameters as probing depth (PD), clinical attachment level (CAL), recession height (RH), keratinized mucosa height (KMH), keratinized mucosa width (KMW), bleeding on probing (BOP), plaque index (PI) and percentage of root coverage (%RC) were evaluated by a blinded calibrated examiner at baseline, 3, 6, 12 months. Dentinal hyperestesia (HYPER) and patient esthetic perception (EST) were recorded in a visual analogic scale at baseline, 7 and 14 days, 1, 3, 6,and 12 months. Statistical analysis of CAL values was done with ANOVA complemented by Tukey. Friedmans complemented by Wilcoxons test evaluated intragroup data, while Kruskal-Wallis was applied for intergroup data. Comparison for %RC was done by Kruskal-Wallis complemented by Dunnet (p<0.05). Reduction in CAL was observed in all groups, with higher numbers for CA (0.55±1.68) and aPDT (0.80±2.11) in relation to C (2.50±1.99) (p<0.05). A higher reduction in RH was observed for CA (0.40±0.62) compared to C (1.15±1.04) (p<0.05). There was an improvement of KMH and KMW for all groups, but with higher values of KMW for aPDT (2.80±0.733) and CA (2.33±0.60) in relation to C (1.99±0.65) (p<0.05). There were no differences for PD (p>0.05). There was a significant higher %RC for CA (82%±30%) and aPDT (82%±28%) in relation to C (58%±40%) (p<0.05). In general, BOP and PI were similar for all groups and periods (p>0.05). There was a significant reduction in hyperestesia along time, but for CA (1.20±2.23) and aPDT (0.70±1.15) the reduction was higher than C (2.63±2.22) (p<0.05). Esthetic perception was improved along time with higher values for CA (9.40±0.96) than C (9.40±0.96) (p<0.05). In conclusion, root biomodification agents as CA and aPDT favored recession coverage by STCG, resulting in reduction of dentin hypersensitivity, higher percentage of root coverage and more sites with total coverage. Additionally, these results had a long-term stability.

A cárie dental ainda afeta grande número de pessoas no mundo todo. Sua ocorrência depende da formação, sobre a superfície dentária, de um biofilme microbiano. As interações entre microrganismos do biofilme e os componentes da dieta, podem interferir de diferentes formas nessa patologia, pois alguns componentes alimentares atuam favorecendo o aparecimento de lesões, tal como os carboidratos, enquanto outros, atuam inibindo, como ácidos graxos, polifenóis, caseína e lectina. O tucumã (Astrocaryum vulgare) e a pupunha (Bactries gasipae) são frutos oleaginosos nativos da Região Amazônica, que apresentam alto teor lipídico e de carotenos. Assim, o objetivo deste estudo foi avaliar a influência dos óleos extraídos da polpa destes frutos na composição do biofilme dental e dinâmica do processo de desmineralização em esmalte. Os óleos foram extraídos sem adição de solventes, caracterizados e misturados a uma solução de 20% de sacarose, para serem testados por meio de um modelo de estudo in situ. Oito voluntários utilizaram dispositivos palatinos contendo 4 blocos de esmalte dental, durante 3 fases de 14 dias cada (n=96). As soluções controle (sacarose 20%) e as soluções com óleos testadas, foram aplicadas sobre os blocos de esmalte 8 vezes ao dia, de 2 em 2 horas. A cada 7 dias, foram coletados 2 blocos de esmalte e o biofilme formado sobre esses blocos. A análise do biofilme compreendeu avaliação da quantidade de unidades formadoras de colônia (UFC) de Streptococcus mutans, Streptococcus totais e Lactobacillus casei; dosagem de carboidratos totais e dosagem da capacidade antioxidante equivalente ao Trolox (TEAC). A perda mineral dos blocos de esmalte foi avaliada por meio da microdureza superficial Knoop e Tomografia por Coerência Óptica (OCT). Utilizou-se o programa BioEstat 5.0 para a análise estatística, com nível de significância de ?=0,05. A análise do biofilme mostrou que o grupo tucumã (GT)-14dias e grupo pupunha (GP)-7dias apresentaram a menor quantidade de UFC do total de microrganismos, diferindo estatisticamente dos grupos sacarose (GS)-7 e 14dias, GT-7dias e GP-14dias (p<0,05). O grupo GT-7 e 14 dias mostraram dosagens de TEAC semelhantes estatisticamente ao grupo GS-7 e 14dias. O grupo GP apresentou os menores valores de TEAC e de carboidratos totais. Não houve diferença estatística intragrupos nos diferentes tempos experimentais, relacionados ao TEAC e carboidratos totais. A análise da perda de dureza superficial (PDS), coeficiente de atenuação óptica e área sob a curva do sinal de OCT mostraram que o grupo GP-7dias apresentou a menor perda mineral superficial e subsuperficial. A variável TEAC revelou correlação positiva moderada com carboidratos, Streptococcus mutans, Streptococcus totais e PDS sugerindo que o ambiente redox possa ter influenciado e mediando as reações no biofilme. Concluiu-se que os óleos testados reduziram a agregação bacteriana e a perda mineral, sendo que o óleo de tucumã apresentou efeito tardio, enquanto que o óleo da pupunha mostrou resultado mais imediato. O óleo da pupunha por ter apresentado ação nos processos iniciais de formação do biofilme pode ser considerado mais efetivo na prevenção à cárie dental. / Dental caries still affects many people worldwide. Its occurrence depends on the formation of a biofilm on the tooth surface. The interaction between biofilm microorganisms and the components of the diet can interfere in different ways in this pathology, as some food components act favoring the appearance of lesions, such as carbohydrates, while others, act by inhibiting it, such as fatty acids, polyphenols, casein and lectin. Tucumã (Astrocaryum vulgare) and peach palm (Bactries gasipae) are oleaginous fruits native from the Amazonia, which have a high lipid content and carotenes. The objective of this study was to evaluate the influence of the oils extracted from the pulp of these fruits on dental biofilm composition and dynamics of enamel demineralization. The oils were extracted without addition of solvents, characterized and mixed with a 20% sucrose solution, to be tested under an in situ study model. Eight volunteers wore palatal appliances containing 4 dental enamel blocks during 3 phases of 14 days each (n = 96). The control (20% sucrose) and experimental solutions (addition of the oils) were applied on the enamel blocks 8 times per day, every 2 hours. Every 7 days 2 enamel blocks were removed and biofilm formed on their surfaces were collected. The analysis comprised the assessment of biofilm forming units (CFU) of Streptococcus mutans, Streptococcus total and Lactobacillus casei, and the dosage of both the total carbohydrates and the Trolox equivalent antioxidant capacity (TEAC). The mineral loss of enamel blocks was evaluated by Knoop microhardness and Optical Coherence Tomography (OCT). The BioEstat 5.0 was used for statistical analysis with a significance level of ? = 5%. The biofilm analysis showed the least amount of CFU of total microorganisms on group tucumã (GT)-14days and group pupunha (GP)-7days, differing from groups of sucrose (GS)-7 and 14days, GT-7days and GP-14days (p<0,05). The GT-7 and 14days showed statistically similar doses of TEAC compared to groups GS-7 and 14days. The GP group showed the lowest values of TEAC and total carbohydrates. With respect to TEAC and total carbohydrates, there was no statistical difference among groups in different experimental times. The analysis of surface hardness (SMH) loss, optical attenuation coefficient and area under the curve of the OCT signal showed that group GP-7days had the lowest surface and subsurface mineral loss. The TEAC variable showed moderate positive correlation with carbohydrates, Streptococcus mutans, Streptococcus total and SMH, suggesting that the environment is influencing and mediating redox reactions in the biofilm. It was concluded that all the oils reduced bacterial aggregation and mineral loss, and that the tucumã oil presented a late effect, while the peach palm oil showed a most immediate result. As the peach palm oil was shown to act during the initial processes of biofilm formation it can be considered more effective in preventing dental caries.