A polpa dentária pode responder a uma agressão pela produção de dentina reacional e reparativa. Osteopontina (OPN), proteína abundante no osso, e proteína da matriz dentinária 1 (DMP1) podem estar presentes nessas dentinas. O objetivo do trabalho foi examinar a ultra-estrutura e a presença da OPN e DMP1 na dentina induzida pela extrusão de incisivos. Os incisivos de ratos foram extruídos e depois reposicionados. Após períodos de tempo determinados, as maxilas foram processadas para MET, MEV e imunocitoquímica. Após extrusão, houve formação de dentina reacional e reparativa, as quais variaram em aspecto, espessura e células secretoras. A OPN foi observada apenas na dentina reparativa num padrão semelhante ao encontrado no osso. A DMP1 foi detectada na matriz em mineralização de todas as dentinas estudadas, mas praticamente não foi observada nas suas pré-dentinas, o que confirmou o seu papel na mineralização. Tais achados mostraram que a dentina reparativa e o osso primário, além de semelhantes morfologicamente, são também similares com relação às suas composições / Reactionary dentine (Rc) and (Rp) reparative dentine are two strategies used by the dentine?pulp complex to respond to injury. Osteopontin (OPN) and dentine matrix protein 1 (DMP1) may be present in the matrix secreted after tissue injury. The aim of the present study was to examine the ultrastructure, as well as the presence of OPN and DMP1 in Rc and Rp by provoking extrusion of the rat incisor. The right upper incisors of rats were extruded and then repositioned. After certain periods of time, the maxillae were processed for scanning and transmission electron microscopy and for immunocytochemistry. After extrusive trauma, there was formation of Rc and Rp, which varied in aspect and thickness. OPN was only detected in the Rp in a pattern similar to bone. DMP1 was immunodetected in all the dentine types, but rare colloidal gold particles were observed in predentin, that confirmed its role in mineralization. The present findings showed that Rp shares some compositional characteristics with primary bone, especially in relation to its OPN content

Yes / In 2015, a previously unknown enclosed settlement and burial ground was found near the summit of a low hill in Ranelagh townland, just north of Roscommon town. The site—officially designated Ranelagh 1, and hereafter referred to variously as ‘the Ranelagh site’, ‘the site at Ranelagh’ or simply ‘Ranelagh’—was excavated over a 54-week period by Excavation Director Shane Delaney for Irish Archaeological Consultancy (IAC) Ltd between October 2015 and October 20161 . Excavations revealed that the site was established during the fourth century AD; for over 1,000 years, until the final phase of burial activity proper concluded there shortly after AD 1400, the site would have been a prominent feature in both the geographical and psychological landscape of the time. Cillín (children’s) burials continued at the site until about AD 1650, further asserting this prominence.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Reproduction de : Thèse d'exercice : Chirurgie dentaire : Nantes : 2008. / Bibliogr.

Terapia fotodinÃmica à um conceito de tratamento, sugerido pela literatura como uma potencial terapia capaz de proporcionar inativaÃÃo microbiana. Desta forma, este estudo avaliou a aÃÃo da terapia fotodinÃmica sobre lesÃes de cÃrie dentinÃria, mediante um delineamento in situ de Ãnica fase. Durante 14 dias, 20 voluntÃrios utilizaram dispositivos intra-orais palatinos, contendo, cada um, seis blocos de dentina humana. Todos os voluntÃrios foram instruÃdos a gotejar sobre os blocos uma soluÃÃo de sacarose a 40% dez vezes ao dia, simulando um desafio cariogÃnico e a utilizar dentifrÃcio fluoretado trÃs vezes ao dia. No final deste perÃodo clÃnico, os blocos foram randomicamente alocados em um dos seguintes grupos: sem fotossensibilizador e luz (F-L-); com fotossensibilizador e sem luz (F+L-); sem fotossensibilizador e com luz com densidade de energia de 47J/cm2(F-L+47); sem fotossensibilizador e com luz com densidade de energia de 94J/cm2 (F-L+94); com fotossensibilizador e irradiados com densidade de energia de 47J/cm2(F+L+47); com fotossensibilizador e irradiados com densidade de energia de 94J/cm2(F+L+94). O fotossensibilizador de escolha foi azul de orto-toluidina na concentraÃÃo de 100 &#61549;g/mL e a irradiaÃÃo originada de um diodo emissor de luz (LED) com comprimento de onda predominante em 638,8nm. Amostras de dentina cariada de cada bloco foram coletadas antes e apÃs os tratamentos e analisadas para contagem de microorganismos totais, estreptococos totais, estreptococos grupo mutans e lactobacilos. Os dados das contagens foram transformados em log10, os valores de log reduÃÃo foram obtidos e as diferenÃas estatÃsticas identificadas atravÃs dos testes ANOVA One way e Tukey Kramer (p<0,05). Em ambas as anÃlises, foram observadas diferenÃas estatisticamente significativas entre as contagens microbiolÃgicas antes e depois dos tratamentos nos grupos (F-L+94), (F+L+47), (F+L+94) para todos os microrganismos testados. Concluiu-se que a terapia fotodinÃmica foi efetiva na morte microbiana nos parÃmetros testados e que o tempo de exposiÃÃo da dentina à luz de 10 minutos, tambÃm, promoveu inativaÃÃo microbiana. / Photodynamic therapy is a concept of treatment, suggested by the literature as a potential therapy capable of inactivating microbial. Thus, this study assessed the efficacy of photodynamic therapy on injuries of dentine caries by a in situ design of single phase. During 14 days, 20 volunteers wore intra-oral palatal devices containing six human dental dentine slabs. The volunteers wore asked to drop a 40% sucrose solution onto the slabs ten times per day, in order to simulate a cariogenic challenge and to use fluoride dentifrice three times per day. At the end of the experimental period the slabs were randomly allocated into one of the following groups: without sensitizer and light (S-L-); with sensitizer and without light (S+L-); without sensitizer and irradiated with 47J/cm2 energy density (S-L+47); without sensitizer and irradiated with 94J/cm2 energy density (S-L+94); with sensitizer and irradiated with 47J/cm2 energy density (S+L+47); and with sensitizer and irradiated with 94J/cm2 energy density (S+L+94). The sensitizer of choice was the toluidine blue O at 100 &#61549;g/mL concentration and radiation originated from a light-emitting diode (LED) with a 638,8 nm predominant wavelength. Before and after the treatments, dentine samples were collected and analyzed to figure out the total microorganisms, total streptococci, mutans streptococci and lactobacilli. The data of the counts were transformed into log10.The values of log reduction was achieved and the statistical differences identified by ANOVA One way and Tukey Kramer tests (p<0,05). In both analyses statistically significant difference between the microbial counts before and after treatment in groups (S-L+47), (S+L+94), (S+L+94) for all microorganisms tested are founded. It was concluded that PACT in the tested parameters was effective in promoting microbial death and that the exposure time of dentine to 10 minutes of light was also effective in microbial inactivation.

FundaÃÃo Cearense de Apoio ao Desenvolvimento Cientifico e TecnolÃgico / There is a general consensus that resin-dentin bonds created by contemporary hydrophilic dentin adhesives deteriorate over time. One way to predict how resin-dentin interface would behave over time is aging the specimens in vitro by immersion in different solutions. The objective of this study was to evaluate the effect of immersion in NaOCl solution on the bond interface created by different adhesive systems. For this, it was used 28 human third molars that had superficial dentin exposed and composite build-ups were built on its surface using one of those adhesives, etch-and-rinse: Scothbond Multi-purpose and Single Bond, or self-etch: Clearfil SE and Adper SE. Specimens were cut into nontrimming dentin-composite beams to microtensile testing. After a period of 24 h in distilled water, sticks from each tooth were divided equally into two groups: control or aged in 10% NaOCl for 1 h. Beams were pulled until failure at crosshead speed of 1 mm/min and bond strength was calculated. Fractured sticks were analyzed and classified in: mixed fracture, cohesive in dentin and cohesive in composite; and expressed in percentage. Data from ÂTBS test were statistically analyzed using Kruskal-Wallis and Games-Howell tests. For comparison between control and aging groups was used the Mann-Whitney test (&#945;=0.05). Two specimens from each adhesive were used to investigate the effect of NaOCl on the interfacial morphological characteristics. For that, specimens were cut in only one direction, dentin-resin discs were fixed in a glass-holder and ground with SiC papers under running water. Slices were treated by Massonâs trichrome acid staining technique to evidence collagen exposed zones and analyzed by optical microscopy. ÂTBS results showed that NaOCl solution significantly reduced bond strength comparing with the control groups for all adhesives tested. Scothbond MP (control: 39,95Â12,72; aged: 26,45Â9,90 MPa) showed the highest values and Adper SE (control: 13,21Â3,15; aged 4,95Â2,49) the lowest in both control and aging groups. Clearfil SE (control : 27,02Â6,84; aged: 16,17Â3,79) and Single Bond (control : 26,66Â8,35; aged: 11,77Â4,28) showed no difference in control groups, but after aging, Clearfil SE showed better results. Microscopic images analysis showed that NaOCl acts efficiently on degradation of collagen fibrils for all adhesive systems. Conclusion: Aging in 10% NaOCl solution reduces bond strength and modifies the interfacial morphological characteristics of the adhesive systems tested. / Hà um consenso geral de que a uniÃo resina-dentina criada pelos adesivos dentinÃrios hidrofÃlicos contemporÃneos se deterioram com o tempo. Uma maneira de prever o comportamento da interface adesiva ao longo do tempo à atravÃs do envelhecimento in vitro por imersÃo em diferentes soluÃÃes. O objetivo deste trabalho foi avaliar o efeito da imersÃo em soluÃÃo de NaOCl na interface de uniÃo criada por diferentes sistemas adesivos. Para isso, foram usados 28 terceiros molares humanos que tiveram a dentina coronÃria exposta e um platà de resina composta confeccionado sobre sua superfÃcie apÃs a aplicaÃÃo de um dos seguintes sistemas adesivos, condicionamento total: Scothbond Multi-uso e Single Bond, ou autocondicionantes: Clearfil SE e Adper SE. Os espÃcimes foram cortados pela tÃcnica nontrimming de obtenÃÃo de palitos para o teste de microtraÃÃo. ApÃs um perÃodo de 24 horas em Ãgua destilada, os palitos de cada dente foram igualmente divididos em dois grupos: controle ou envelhecido em soluÃÃo de NaOCl a 10% por 1 hora. Os espÃcimes foram tracionados atà a ruptura da uniÃo a uma velocidade de 1 mm/min e sua forÃa de uniÃo mensurada. Os palitos fraturados foram analisados e classificados em: fratura mista, coesiva em dentina e coesiva em compÃsito, e os valores expressos em porcentagem. Os dados da resistÃncia de uniÃo foram estatisticamente analisados usando os testes Kruskal-Wallis e Games-Howell. Para comparaÃÃo entre os grupos controle e envelhecido foi usado o teste de Mann-Whitney (&#945;=0.05). Dois espÃcimes de cada adesivo foram usados para investigar o efeito do NaOCl nas caracterÃsticas morfolÃgicas da interface de uniÃo. Para isso, espÃcimes foram cortados ao longo eixo em apenas uma direÃÃo e os discos de dentina-resina foram fixados em lÃmina de vidro e desgastados com lixas de SiC sob refrigeraÃÃo com Ãgua. As lÃminas foram tratadas pela tÃcnica de coloraÃÃo Ãcida de Masson para evidenciar as zonas de colÃgeno exposto e observadas atravÃs de microscopia Ãptica. Os resultados do teste de microtraÃÃo mostraram que a soluÃÃo de NaOCl reduziu significativamente a forÃa de uniÃo em comparaÃÃo aos grupos controle para todos os adesivos testados. Scothbond MU (controle: 39,95Â12,72; envelhecido: 26,45Â9,90 MPa) mostrou os maiores valores de uniÃo e Adper SE (controle: 13,21Â3,15; envelhecido 4,95Â2,49) os menores valores, tanto para o grupo controle quanto envelhecido. Clearfil SE (controle: 27,02Â6,84; envelhecido: 16,17Â3,79) e Single Bond (controle: 26,66Â8,35; envelhecido: 11,77Â4,28) nÃo mostraram diferenÃa estatÃstica nos grupos controle, mas apÃs envelhecimento, Clearfil SE mostrou melhores resultados. A anÃlise das imagens microscÃpicas mostrou que o NaOCl agiu efetivamente na degradaÃÃo das fibras de colÃgeno para todos os sistemas adesivos testados. ConclusÃo: O envelhecimento dos espÃcimes em soluÃÃo de NaOCl a 10% reduziu a resistÃncia de uniÃo e modificou as caracterÃsticas morfolÃgicas da interface adesiva para os sistemas adesivos testados.

Self-etching dentine bonding agents are a recent addition to the choice of bonding agents which a clinician has available to bond resin restorations to tooth structure. The so-called ‘traditional’, total-etch fourth and fifth generation dentine bonding agents have proven their clinical abilities and the question now remains whether these ‘new’ self-etching dentine bonding agents will clinically perform as well as the ‘proven’ total-etch dentine bonding agents. For the purpose of this dissertation the author completed three research projects which were performed to evaluate the efficacy of a selection of dentine bonding agents and then used the results to compare some properties (shear bond strength, microleakage, and anti-bacterial properties) of total-etch dentine bonding agents with some self-etching dentine bonding agents. All discussions will focus on the three dentine bonding agent properties evaluated by the three research projects performed. The three specific aims of this study were: <ul> <li> To compare the dentine shear bond strength of a selection of self-etching dentine bonding agents with that of a total-etch dentine bonding agent control.</li> <li> To compare dentine and enamel microleakage values of a selection of self-etching bonding agents with that of a total-etch dentine bonding agent control.</li> <li> To evaluate the possible anti-bacterial properties of a selection of dentine bonding agents, with focus placed on the self-etching dentine bonding agent ABFb (Clearfil Protect Bond).</li></ul> The studies performed by the author achieved comparative/similar results to some studies described in the literature but it is clear from the literature that some studies provide conflicting results, especially leakage of enamel margins when using self-etching bonding agents. Taking into consideration the limitations of the three studies performed, it can be concluded that as far as the three evaluated properties of self-etching dentine bonding agents are concerned, they should prove to be acceptable clinical alternatives for use in place of total-etch dentine bonding agents. Copyright / Dissertation (MSc(Odont))--University of Pretoria, 2010. / Odontology / unrestricted

Philosophiae Doctor - PhD / Introduction: Biocompatibility of all kinds of dental materials is of paramount importance In order to prevent/limit irritation or degeneration of the surrounding tissues where it is applied. Some researchers suggested that dentine bonding agents may be used for pulpal protection, while pulpal inflammation and inhibition of pulpal repair following the use of dentine bonding agents were also reported. Objectives: The first part of this study compared the cytotoxicity of human pulp cell lines to a mouse 3T3 cell line to cytotoxic challenges from dentine bonding agents. The second part of the study compared the cytotoxicity of recent dentine bonding agents namely, Scotchbond 1, Prime & Bond NTand Xeno III through artificial membranes as well as thin dentine discs (after its reaction with apatite) and Clearfil Protect Bond (CPB)as such, as well as the primer part of CPBand the bond part of CPB separately. Methods and Materials: Near confluent human pulp cells and 3T3 cells were exposed to culture medium (DMEM)extractions from the various polymerized agents mentioned above and the cell viability (survival rate) was measured using the standard MTTassay and related to the non-exposed controls. Results: Two human pulp cells lines were more sensitive to 3T3 cell lines while the other human cell line was less sensitive to the 3T3 cell line. All bonding agents as such were found to be cytotoxic towards the 3T3 cells with Xeno III (25%survival rate) and CPB (35%)the most cytotoxic. Of the two parts from CPB the bond part was the least toxic (91% survival rate), but the primer part (containing the anti-bacterial pyridinium molecule) was very toxic (30% survival rate). ScotchBond 1 (59% survival rate) and Prime & Bond NT (62% survival rate) were not statistically different (Kruskal-Wallis Test, p>0.05). However,the survival rate of Xeno III (25% through membrane as well as dentine discs) and Clearfil Protect Bond (35%) were significantly lower than that of the other two bonding agents, with Xeno III significantly the most toxic (p<0.05 ) Conclusion: In general, all 4 dentine bonding agents were cytotoxic of which Xeno III was the most toxic even after its reaction with apatite (through dentine discs). The most toxic part of CPB was found to be the primer part containing the pyridinium linked molecule. If human pulp fibroblasts are used for cytotoxicity testing of dentine bonding agents many cell lines must be used.

Resin based composite is currently one of the most popular dental restoratives. Used as a direct restorative material, it displays many beneficial properties such as excellent micromechanical bonding to enamel, polishability and aesthetics. Despite many advances in dentine bonding agents, dentine bonding remains problematic with microleakage and recurrent caries, being frequent clinical sequelae. The open sandwich technique was developed to overcome two problems: deficient bonding of resin composites to dentine, and inadequate strength and fracture toughness of conventional glass-ionomers (GI). GI displayed excellent cavity sealing abilities by virtue of their chemical adhesion to tooth structure. Resin-modified glass-ionomers (RMGI) were developed to improve on the weaknesses of conventional GI during early setting i.e. setting rate, water sensitivity and strength. Recently literature has reported the use of ultrasonic activation to set conventional GI, opening the possibility of improving the initial properties of the material and suitability for use in the open sandwich technique. The aim of this study was to compare microleakage of Ketac Molar, Ketac Molar set by ultrasound (US), Vitremer and Ketac N100 used in the open sandwich technique, with the control of a resin based composite, Filtek Z250. Two hundred Class II cavities were prepared in a hundred caries free, human, molar teeth, with half of the cervical margins placed apical and the rest coronal to the cemento-enamel junction. For each material, twenty restorations were placed for each cervical position. The sandwich materials were placed to fill the interproximal box level with the pulpal floor, and a final two layers of resin composite was then placed to complete the restoration. Restored teeth were stored in a laboratory oven for 7 days at 37 °C; margins were then finished initially with a medium grit Sof-Lex disc and finally with a fine diamond drill. Material groups were separated into two halfs to commence microleakage testing or thermocycling. Thermocycling was conducted for 500 cycles between 5 °C and 55 °C, with a dwell time of 30 seconds. Restored teeth were then covered with nail varnish around the restoration margins, and immersed in 0.5% basic fuchsin solution for 24 hours. They were then cleaned, embedded in clear self-curing acrylic and sectioned 3 times with an Accutom-2 precision saw, at 2 mm intervals. Sections were evaluated using a light microscope under 4 time’s magnification and microleakage scores given as: 0 = no leakage; 1 = < ½; 2 = > ½ distance to the axial wall/pulpal floor; 3 = leakage up to axial wall/pulpal floor. Statistical analysis was undertaken using Analysis of Variance (ANOVA) for the cervical and occlusal microleakage scores; p-values <0.05 were considered significant. The cervical microleakage results of cavity margins in dentine showed that Ketac Molar (US) performed better than Ketac Molar, and Ketac N100 performed better than Vitremer. Results in enamel showed no significant differences. The use of the open sandwich technique effectively reduced microleakage of cervical cavity margins placed in dentine but failed to reduce occlusal microleakage of Filtek Z250. Copyright / Dissertation (MSc(Odont))--University of Pretoria, 2008. / Odontology / unrestricted

Yes / Objective: This project sought to investigate whether an association may be observed between isotopic stress indicators and skeletal evidence of pathological conditions. Materials: Deciduous and permanent teeth of 15 non-adults from two contemporaneous mid-19th century London burial grounds (City Bunhill, Lukin Street). Methods: δ13C and δ15N was measured in the incrementally sectioned dentine collagen. Isotopic profiles for each individual included death during tooth development. Results: Individuals with skeletal evidence of chronic pathological conditions (e.g., rickets, tuberculosis) exhibited raised δ15N values of 0.5-1.7‰ in the months prior to death. Isotopic change consistent with chronic physiological stress prior to death was also recorded in two individuals with no skeletal evidence of disease. An offset was observed between co-forming bone and dentine δ15N values in both populations, indicating that bone and dentine are not recording the same isotopic changes. Conclusions: Isotopic change consistent with chronic physiological stress was observed in both those with and without skeletal evidence of disease, suggesting that adaptation to chronic stress in childhood was not uncommon within these 19th century London populations. Significance: Chronic physiological stress prior to death may be seen in the incrementally sampled dentine of non-adults who die during tooth formation. Limitations: The temporal resolution of current dentine micro-sampling methods may mask or minimise visibility of shorter-term periods of stress or dietary change. Suggestions for further research: Future research should further explore the relationship between specific skeletal pathologies and isotopic evidence for stress.