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Bahavior and Analysis of an Integral Abutment BridgeHuffaker, Conner D. 01 May 2013 (has links)
In order to quantify the influence of temperature changes on integral abutment bridge movements, thirty-two Sokkia RS30N reflective targets were strategically attached to a bridge along its length. These targets were surveyed every month for twelve consecutive months. These changes in length coincided with restraint conditions between purely fixed and simply supported. Movement of expansion joints was also recorded. The movements of the expansion gaps at opposite corners appear to exhibit similar movements. This behavior indicates a type of twisting motion occurring within the bridge as a result of unequal movements at the east and west sides of each abutment. This motion suggests that the bridge abutments experience forces that incite weak axis bending in the abutments, especially in the north abutment. These quantitative bridge movements were compared to predicted behavior from a finite-element model. A detailed finite-element model of the bridge was created using SAP2000 (Computers and Structures, Inc.) software. The detailed model was developed using solid elements for all components of the bridge except piles and bents. Longitudinal surface springs were placed at the abutment elements in order to simulate the soil-abutment interaction. A typical temperature load was assigned to the bridge deck and girder elements to compare the calculated stress concentrations in the model with the observed cracking on the abutment. The model produced high stress concentrations in the abutment adjacent to the bottom girder flange. This corresponded to the same location of observed cracking. The finite-element model also showed lateral movement of the north abutment. This lateral abutment contributed to the unequal movements of the bridge spans. Once the comparison between the measured bridge behavior of the survey and the findings of the detailed finite element model was completed, a simplified model was used to evaluate the bending moment and stresses in the abutment of the 400 South Street Bridge. The simplified model was also used to perform a parametric study on the influence of skew, span length, and temperature gradient on weak-axis abutment moments.
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Mätning av Mikroläckage i Dentala ImplantatLöfgren, Jonas, Karlsson, Maria January 2007 (has links)
<p>Osseointegrated titanium implants have become a commonly used method in edentulous jaws and today there are success rates in the magnitude of 82 % in the lower jaw and 98 % in the upper. During first year after implantation a fully normal marginal bone loss of 1-2 mm occurs. If the bone loss continues there is a risk of implant failure. High tensions in bone and inflammation caused by bacteria are possible reasons for this problem. It has been shown that a leakage of bacterias occurs between the parts of the implant and there are theories that this has effects on the marginal bone loss.</p><p>The aim of this thesis has been to increase the knowledge about microbial leakage with help of in vitro tests and virtual simulations. The goal was to create a test method to measure differences of microbial leakage in two implant systems.</p><p>The developed test method includes an in vitro test of six implants and Finite Element Analysis. The test method is the product of a process with several small tests. The final test method measures leakage of a coloured fluid with a spectrophotometer. The results are then compared with the virtual simulations to draw conclusions and find explanations how the implants are functioning.</p><p>The result of test on six implants, four Ospol and two Nobel Replace, indicates that there are differences in the magnitude of microleakage in different implant systems in due to the implant-abutment interface. No conclusions can be drawn before the test method is refined and more implants are tested.</p>
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Mätning av Mikroläckage i Dentala ImplantatLöfgren, Jonas, Karlsson, Maria January 2007 (has links)
Osseointegrated titanium implants have become a commonly used method in edentulous jaws and today there are success rates in the magnitude of 82 % in the lower jaw and 98 % in the upper. During first year after implantation a fully normal marginal bone loss of 1-2 mm occurs. If the bone loss continues there is a risk of implant failure. High tensions in bone and inflammation caused by bacteria are possible reasons for this problem. It has been shown that a leakage of bacterias occurs between the parts of the implant and there are theories that this has effects on the marginal bone loss. The aim of this thesis has been to increase the knowledge about microbial leakage with help of in vitro tests and virtual simulations. The goal was to create a test method to measure differences of microbial leakage in two implant systems. The developed test method includes an in vitro test of six implants and Finite Element Analysis. The test method is the product of a process with several small tests. The final test method measures leakage of a coloured fluid with a spectrophotometer. The results are then compared with the virtual simulations to draw conclusions and find explanations how the implants are functioning. The result of test on six implants, four Ospol and two Nobel Replace, indicates that there are differences in the magnitude of microleakage in different implant systems in due to the implant-abutment interface. No conclusions can be drawn before the test method is refined and more implants are tested.
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Three Dimensional Displacement of Nine Different Abutments for Cement-Retained Crowns Using a Specific Torqueing Protocol on a Tapered Screw-Vent ImplantGilbert, Andy Ben January 2013 (has links)
No description available.
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A Comparison of Zirconia and Titanium Abutments for MicroleakageABDELHAMED, MOHAMED IBRAHIM 01 September 2010 (has links)
No description available.
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Análise quantitativa do corante azul de Evan extravasado do interior das câmaras internas dos implantes por suas interfaces protéticas nas condições: Hexágono Externo (HE) - Hexágono Interno (HI) - Cone Morse (CM) / Quantitative analysis of Evans blue dye leakage from internal implant chambers through their prosthetic interfaces under the following conditions: External Hexagon (HE) Internal Hexagon (IH) Morse Cone (MC)Auler e Salles, Murilo 06 September 2011 (has links)
Busca-se em pesquisas e estudos avaliar a capacidade de adaptação e selamento entre a conexão implante/intermediário de diferentes sistemas de implantes odontológicos. Observou-se recentemente que implantes com abutments retidos com parafusos, diversos fenômenos como afrouxamento e fratura do parafuso, rotação e fratura do abutment com penetração bacteriana nas câmaras internas dos implantes, acontece como conseqüência da desadaptação interface implante/abutment. É descrito ao nível desta região um pequeno espaço microgap, fator relevante para remodelamento da crista óssea e longevidade da saúde dos tecidos moles periimplantares. O propósito do estudo foi investigar o extravasamento da solução do corante azul de Evan em três tipos de implantes e seus respectivos intermediários, durante um período de seis (6) dias, a cada vinte e quatro (24) horas, com intervalo em cento e vinte (120) horas, através da agitação proporcionada por uma mesa agitadora. Para tal, foram utilizados trinta (30) implantes, dez (10) de cada tipo, com seus respectivos intermediários protéticos, minipilares, sendo o Grupo Um (1) de implantes Hexágono Externo (HE), Grupo dois (2) de Hexágono Interno (HI) e Grupo três (3) de Cone Morse (CM). No interior de cada implante foi pipetado volume ou quantidade proporcional ao seu espaço interno uma solução de corante azul de Evan. Após a colocação do corante no interior dos implantes, os abutments ou intermediários foram acoplados e aparafusados com torque de vinte (20) Ncm, através do torquímetro de Gauge (Tohnichi), e estes depositados individualmente em micro tubos de cor âmbar na condição de intermediários voltados para baixo. Segui/se imediatamente a colocação de (1)ml de água deionizada. A seguir os tubos foram fechados hermeticamente e posicionados numa mesa suporte para microtubos e foram armazernados por 24 horas, sem agitação. Posteriormente foram agitados por 10 minutos com movimentos uniformes em mesa agitadora e a partir deste momento iniciou/se a coleta de uma pequena quantidade de água de cada micro tubo onde por sua vez estas amostras foram analisadas por absorbância através do método de fotometria, espectrofotometria, onde mostraram o extravasamento da solução do corante azul de Evan nos sistemas de implantes usados. Do inicio da coleta das amostras no tempo de (24 horas) até a condição no terceiro dia ou setenta e duas horas, os três sistemas não mostraram/se alterações estatisticamente significantes. A partir do tempo quarto dia ou 96 h., no sistema do grupo Cone Morse, revelou diferenças estatisticamente significantes entre o grupo HE e HI. Os resultados foram tabulados e o teste estatístico Anova há dois critérios e aplicados a eles o teste Tukey comparação entre todos, com o nível de significância de p<0.05. Os resultados do teste de vinte e quatro (24); quarenta e oito (48), setenta e duas (72), não havendo diferenças estatisticamente significantes, ao passo que no período de noventa e seis (96) e cento e quarenta e quatro(144) horas, mostrou a solução do corante de azul de Evan do sistema CM, o xtravasamento estatisticamente significante maior do que nos grupos HE e HI. Conclui/se, portanto, que houve extravasamento nos três sistemas na condição inicial. No tempo 96 houve um maior extravasamento do sistema CM perpetuando até o final do experimento, mostrando-se estaticamente diferente em relação aos sistemas HE e HI. / Research and studies seek to evaluate the capacity of adaptation and sealing between the implant-intermediate connections of different dental implant systems. It has recently been observed that in implants with screw-retained abutments, various phenomena, such as screw4 loosening and fracture, rotation and fracture of the abutment with bacterial penetration into the internal chambers of the implants have occurred as a result of maladaptatation at the implant-abutment interface. At the level of this region, a small space known as a microgap is described, and is a relevant factor in remodeling of the crestal bone and peri-implant soft tissue health in the long term. The purpose of this study was to investigate the extravasation of Evans blue dye solution in three types of implants and their respective intermediates during a period of six (6) days, every twenty-four (24) hours, with an interval in one hundred and wenty (120) hours, by means of agitation provided by an agitating table. To do this, thirty (30) implants were used, ten (10) of each type, with their respective prosthetic intermediates and mini-abutments, divided into groups as follows: Group One (1) External Hexagon implants (EH), Group Two (2) Internal Hexagon (IH) and Group three (3) Morse Cone (MC). Into the interior of each implant, Evans blue dye solution was inserted with a pipette in a volume or quantity proportional to its internal space. After the dye was put into the implants, the abutments or intermediates were coupled and the screws tightened to a torque of twenty (20) Ncm, with a Gauge torque meter (Tohnichi), and they were individually deposited in amber-colored microtubes positioned so that the intermediates faced downwards. This was immediately followed by the placement of (1)ml of deionized water. Next, the tubes were hermetically closed and placed on a table with a microtube holder and stored for 24 hours, without agitation. Afterwards they were agitated for 10 minutes on an agitating table making uniform movements and from then on, a small quantity of water began to be collected from each microtube, where in turn these samples were analyzed by absorbance method of photometry, spectrophotometry, in which they showed the extravasation of the Evans blue dye solution in the implant system used. From the beginning of sample collection at the time of (24hours) until the condition on the third day or at seventy-two hours, the three systems showed no statistically significant alterations. From the fourth day, or at the time of 96 h., in the Morse Cone Group system, statistically significant differences were revealed between Group EH and IH. The results were tabulated and the ANOVA statistical test for two criteria and the Tukey test were applied for comparison among all the groups, with a level of significance of p<0.05. The results of the twenty-four-hour (24); forty-eight (48), seventy-two hour tests (72), there were no statistically significant differences, whereas in the period of ninety-six (96) and one hundred and forty-four (144) hours, showed the Evans blue dye solution extravasation from the MC system to be greater with statistical significance than in Groups EH and IH. It was therefore concluded that there was extravasation in the three systems in the initial condition. At the time of 96 there was greater extravasation from the MC system, which was perpetuated up to the end of the experiment, showing it to differ statistically in comparison with the EH and IH systems.
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Análise quantitativa do corante azul de Evan extravasado do interior das câmaras internas dos implantes por suas interfaces protéticas nas condições: Hexágono Externo (HE) - Hexágono Interno (HI) - Cone Morse (CM) / Quantitative analysis of Evans blue dye leakage from internal implant chambers through their prosthetic interfaces under the following conditions: External Hexagon (HE) Internal Hexagon (IH) Morse Cone (MC)Murilo Auler e Salles 06 September 2011 (has links)
Busca-se em pesquisas e estudos avaliar a capacidade de adaptação e selamento entre a conexão implante/intermediário de diferentes sistemas de implantes odontológicos. Observou-se recentemente que implantes com abutments retidos com parafusos, diversos fenômenos como afrouxamento e fratura do parafuso, rotação e fratura do abutment com penetração bacteriana nas câmaras internas dos implantes, acontece como conseqüência da desadaptação interface implante/abutment. É descrito ao nível desta região um pequeno espaço microgap, fator relevante para remodelamento da crista óssea e longevidade da saúde dos tecidos moles periimplantares. O propósito do estudo foi investigar o extravasamento da solução do corante azul de Evan em três tipos de implantes e seus respectivos intermediários, durante um período de seis (6) dias, a cada vinte e quatro (24) horas, com intervalo em cento e vinte (120) horas, através da agitação proporcionada por uma mesa agitadora. Para tal, foram utilizados trinta (30) implantes, dez (10) de cada tipo, com seus respectivos intermediários protéticos, minipilares, sendo o Grupo Um (1) de implantes Hexágono Externo (HE), Grupo dois (2) de Hexágono Interno (HI) e Grupo três (3) de Cone Morse (CM). No interior de cada implante foi pipetado volume ou quantidade proporcional ao seu espaço interno uma solução de corante azul de Evan. Após a colocação do corante no interior dos implantes, os abutments ou intermediários foram acoplados e aparafusados com torque de vinte (20) Ncm, através do torquímetro de Gauge (Tohnichi), e estes depositados individualmente em micro tubos de cor âmbar na condição de intermediários voltados para baixo. Segui/se imediatamente a colocação de (1)ml de água deionizada. A seguir os tubos foram fechados hermeticamente e posicionados numa mesa suporte para microtubos e foram armazernados por 24 horas, sem agitação. Posteriormente foram agitados por 10 minutos com movimentos uniformes em mesa agitadora e a partir deste momento iniciou/se a coleta de uma pequena quantidade de água de cada micro tubo onde por sua vez estas amostras foram analisadas por absorbância através do método de fotometria, espectrofotometria, onde mostraram o extravasamento da solução do corante azul de Evan nos sistemas de implantes usados. Do inicio da coleta das amostras no tempo de (24 horas) até a condição no terceiro dia ou setenta e duas horas, os três sistemas não mostraram/se alterações estatisticamente significantes. A partir do tempo quarto dia ou 96 h., no sistema do grupo Cone Morse, revelou diferenças estatisticamente significantes entre o grupo HE e HI. Os resultados foram tabulados e o teste estatístico Anova há dois critérios e aplicados a eles o teste Tukey comparação entre todos, com o nível de significância de p<0.05. Os resultados do teste de vinte e quatro (24); quarenta e oito (48), setenta e duas (72), não havendo diferenças estatisticamente significantes, ao passo que no período de noventa e seis (96) e cento e quarenta e quatro(144) horas, mostrou a solução do corante de azul de Evan do sistema CM, o xtravasamento estatisticamente significante maior do que nos grupos HE e HI. Conclui/se, portanto, que houve extravasamento nos três sistemas na condição inicial. No tempo 96 houve um maior extravasamento do sistema CM perpetuando até o final do experimento, mostrando-se estaticamente diferente em relação aos sistemas HE e HI. / Research and studies seek to evaluate the capacity of adaptation and sealing between the implant-intermediate connections of different dental implant systems. It has recently been observed that in implants with screw-retained abutments, various phenomena, such as screw4 loosening and fracture, rotation and fracture of the abutment with bacterial penetration into the internal chambers of the implants have occurred as a result of maladaptatation at the implant-abutment interface. At the level of this region, a small space known as a microgap is described, and is a relevant factor in remodeling of the crestal bone and peri-implant soft tissue health in the long term. The purpose of this study was to investigate the extravasation of Evans blue dye solution in three types of implants and their respective intermediates during a period of six (6) days, every twenty-four (24) hours, with an interval in one hundred and wenty (120) hours, by means of agitation provided by an agitating table. To do this, thirty (30) implants were used, ten (10) of each type, with their respective prosthetic intermediates and mini-abutments, divided into groups as follows: Group One (1) External Hexagon implants (EH), Group Two (2) Internal Hexagon (IH) and Group three (3) Morse Cone (MC). Into the interior of each implant, Evans blue dye solution was inserted with a pipette in a volume or quantity proportional to its internal space. After the dye was put into the implants, the abutments or intermediates were coupled and the screws tightened to a torque of twenty (20) Ncm, with a Gauge torque meter (Tohnichi), and they were individually deposited in amber-colored microtubes positioned so that the intermediates faced downwards. This was immediately followed by the placement of (1)ml of deionized water. Next, the tubes were hermetically closed and placed on a table with a microtube holder and stored for 24 hours, without agitation. Afterwards they were agitated for 10 minutes on an agitating table making uniform movements and from then on, a small quantity of water began to be collected from each microtube, where in turn these samples were analyzed by absorbance method of photometry, spectrophotometry, in which they showed the extravasation of the Evans blue dye solution in the implant system used. From the beginning of sample collection at the time of (24hours) until the condition on the third day or at seventy-two hours, the three systems showed no statistically significant alterations. From the fourth day, or at the time of 96 h., in the Morse Cone Group system, statistically significant differences were revealed between Group EH and IH. The results were tabulated and the ANOVA statistical test for two criteria and the Tukey test were applied for comparison among all the groups, with a level of significance of p<0.05. The results of the twenty-four-hour (24); forty-eight (48), seventy-two hour tests (72), there were no statistically significant differences, whereas in the period of ninety-six (96) and one hundred and forty-four (144) hours, showed the Evans blue dye solution extravasation from the MC system to be greater with statistical significance than in Groups EH and IH. It was therefore concluded that there was extravasation in the three systems in the initial condition. At the time of 96 there was greater extravasation from the MC system, which was perpetuated up to the end of the experiment, showing it to differ statistically in comparison with the EH and IH systems.
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An in vitro assessment of the bacterial sealing capacity of narrow diameter implants with Morse-taper abutment connections.Alriyahi, Mubarak January 2020 (has links)
Magister Scientiae Dentium - MSc(Dent) / Lack of appropriate bone thickness is a common clinical limitation for tooth replacement, often requiring narrow implants, which have shown better results when combined with Morse taper connections. Little is known about the sealing of the abutment-implant interface of narrow implants with Morse taper connections against oral bacteria.
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Morphological and Morphometric Comparison of Interface in Original Abutment and Copy Compatible Abutment Connected to Original ImplantBerggren, Sara, Shishkina, Tatiana January 2016 (has links)
I nuläget finns flertalet företag som tillverkar distanser som är kompatibla med originalimplantat. Det finns dock ingen evidens för att dessa distanser är likvärdiga med originaldistanser när de används på originalimplantat. God passform hos implantatkomponenter är en viktig faktor för att undvika biologiska och tekniska komplikationer.Syftet med den här studien var att jämföra passformen mellan originaldistans och originlimplantat med kompatibel kopiadistans och originalimplantat.Material och metod: Fem originaldistanser och fem kompatibla distanser skruvades till originalimplantat. Provkroppar bäddades in och delade på mitten för att sedan analyseras i ljusmikroskop och SEM. Där mättes kontaktytans längd och mellanrummet mellan implantat och distans och distans och distansskruv. All data analyserades i SPSS.Resultatet: Implantatkoplex med kopiadistans hade fem gånger kortare kontaktyta mellan komponenterna och mellanrummet var större, vilket ger en försämrad stabilitet under andvändning. Analysen av distansskruvens yta visade morfologiska skillnader mot den inre ytan av distansen vilket kan leda till deformation och/eller fraktur av skruven.Konklusion: Användning av lågpris kopiadistanser till Astra originalimplantat kan leda till signifikant avvikande passform hos distansen och en lägre tolerans för stress hos distansskruven. / Nowadays there exist different abutments from different companies that are compatible to a certain manufacturer implant. But no scientific evidence exists on whether the fit of the compatible abutments are comparable to that of the genuine abutments when connected to the genuine implants. God fitting of implant components is an essential factor to avoid microgap formation in implant-abutment interface due to microgaps lead to biological and biomechanical complications. The aim of this study was to compare interface in original abutment and copy compatible abutment connected to original implant.Material and Methods: Five original abutments and five compatible abutments were connected to the original implants. The complex were sectioned in the middle and thereafter analyzed in a light microscope and SEM by measuring contact length and interface thickness between the implant and abutment and also between the abutment and abutment screw. All data was analyzed with SPSS-program.Result: Compatible implant complex had about five times shorter contact surface between components and interface was thicker which gives less stability under clinical function. The analyze of screw-abutment interface showed morphologic differences with the inner surface of the abutment which could lead to screw deformation and even fracture.Conclusion: Using low-cost compatible abutments connected to original Astra implants could lead to significant fit discrepancy of the copy abutments and lower stress tolerance in the abutment screw.
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Epithelial cells attachment on five different dental implant abutment surface candidatesSitbon, Yves Alain Dietrich 01 May 2009 (has links)
Objectives: the hypothesis of this study was that different abutment substrates would not affect epithelial cell attachment and differentiation.
Methods: 15 discs for each of 5 different materials (4 types of titanium and 1 type of zirconium) were flooded with a media containing human adenoid epithelial cells (hTERT). Cells were allowed to attach on the discs for 2 hours. The media was then collected, and remaining suspended cells counted, to determine number of attached cells. Surfaces were then flooded with fresh media, collected 24 hours later. Levels of 6 different pro-inflammatory cytokines contained in the media were measured for each disc, using a Luminex 100 IS system. Then, part of the discs was used for SEM observation of cell morphology. Another part of the discs was used for immuno-fluorescent microscopy, to observe the organization of the actin cytoskeleton, using phalloidin conjugated to a fluorophore to label the actin. The remaining discs were used to analyse alpha6-beta4 Integrin expression, using gel electrophoresis after isolation of mRNA and reverse PCR.
Results: Number of attached cells was not statistically different for the 5 types of material. For the 5 materials, levels of cytokines IL-6, 8, 12 and TNF-alpha were similar and IL-1 and 10 were not produced in amounts large enough to be detected. Again, alpha6-beta4 Integrin expression was similar for the different surfaces. Actin Cytoskeleton organization was alike for the titanium surfaces, but cells seemed to be less spread on zirconium. SEM showed comparable cell morphology for the titanium surfaces, whereas no cell could be observed on zirconium.
Conclusions: quantitatively, cell attachment and expression of alpha6-beta4 Integrin, IL-6, 8, 12 and TNF-alpha does not seem to be affected by the different surfaces. Nevertheless, attachment might be of lesser quality for zirconium.
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