The Experts below are selected from a list of 24495 Experts worldwide ranked by ideXlab platform
Mark R. Geier - One of the best experts on this subject based on the ideXlab platform.
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New science challenges old notion that mercury dental Amalgam is safe
BioMetals, 2014Co-Authors: Kristin G Homme, Paul G King, Boyd E Haley, Lisa K Sykes, Janet K Kern, David A. Geier, Mark R. GeierAbstract:Mercury dental Amalgam has a long history of ostensibly safe use despite its continuous release of mercury vapor. Two key studies known as the Children’s Amalgam Trials are widely cited as evidence of safety. However, four recent reanalyses of one of these trials now suggest harm, particularly to boys with common genetic variants. These and other studies suggest that susceptibility to mercury toxicity differs among individuals based on multiple genes, not all of which have been identified. These studies further suggest that the levels of exposure to mercury vapor from dental Amalgams may be unsafe for certain subpopulations. Moreover, a simple comparison of typical exposures versus regulatory safety standards suggests that many people receive unsafe exposures. Chronic mercury toxicity is especially insidious because symptoms are variable and nonspecific, diagnostic tests are often misunderstood, and treatments are speculative at best. Throughout the world, efforts are underway to phase down or eliminate the use of mercury dental Amalgam.
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evidence supporting a link between dental Amalgams and chronic illness fatigue depression anxiety and suicide
Neuro endocrinology letters, 2014Co-Authors: Janet K Kern, Paul G King, Kristin G Homme, Boyd E Haley, Lisa K Sykes, David A. Geier, Geir Bjørklund, Mark R. GeierAbstract:The purpose of this review is to examine the evidence for a relationship between mercury (Hg) exposure from dental Amalgams and certain idiopathic chronic illnesses - chronic fatigue syndrome (CFS), fibromyalgia (FM), depression, anxiety, and suicide. Dental Amalgam is a commonly used dental restorative material that contains approximately 50% elemental mercury (Hg0) by weight and releases Hg0 vapor. Studies have shown that chronic Hg exposure from various sources including dental Amalgams is associated with numerous health complaints, including fatigue, anxiety, and depression - and these are among the main symptoms that are associated with CFS and FM. In addition, several studies have shown that the removal of Amalgams is associated with improvement in these symptoms. Although the issue of Amalgam safety is still under debate, the preponderance of evidence suggests that Hg exposure from dental Amalgams may cause or contribute to many chronic conditions. Thus, consideration of Hg toxicity may be central to the effective clinical investigation of many chronic illnesses, particularly those involving fatigue and depression. Language: en
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a significant dose dependent relationship between mercury exposure from dental Amalgams and kidney integrity biomarkers a further assessment of the casa pia children s dental Amalgam trial
Human & Experimental Toxicology, 2013Co-Authors: David A. Geier, Paul G King, Thomas J Carmody, Janet K Kern, Mark R. GeierAbstract:Dental Amalgams are a commonly used dental restorative material. Amalgams are about 50% mercury (Hg), and Hg is known to significantly accumulate in the kidney. It was hypothesized that because Hg accumulates in the proximal tubules (PTs), glutathione-S-transferases (GST)-α (suggestive of kidney damage at the level of PT) would be expected to be more related to Hg exposure than GST-π (suggestive of kidney damage at the level of the distal tubules). Urinary biomarkers of kidney integrity were examined in children of 8–18 years old, with and without dental Amalgam fillings, from a completed clinical trial (parent study). Our study determined whether there was a significant dose-dependent correlation between increasing Hg exposure from dental Amalgams and GST-α and GST-π as biomarkers of kidney integrity. Overall, the present study, using a different and more sensitive statistical model than the parent study, revealed a statistically significant dose-dependent correlation between cumulative exposure to Hg fr...
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a dose dependent relationship between mercury exposure from dental Amalgams and urinary mercury levels a further assessment of the casa pia children s dental Amalgam trial
Human & Experimental Toxicology, 2012Co-Authors: David A. Geier, Paul G King, Thomas J Carmody, Janet K Kern, Mark R. GeierAbstract:Dental Amalgams are a commonly used dental restorative material, and Amalgams are about 50% mercury (Hg). In our study, urinary Hg levels was examined in children of age 8–18 years, with and without dental Amalgam fillings, from a completed clinical trial (parent study) that was designed to evaluate the potential health consequences of prolonged exposure to Hg from dental Amalgam fillings. Our study was designed to determine whether there was a significant dose-dependent correlation between increasing Hg exposure from dental Amalgams and urinary Hg levels. Hg exposure depends on the size and number of teeth with dental Amalgams. Overall, consistent with the results observed in the parent study, there was a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental Amalgams and urinary Hg levels, after covariate adjustment. Further, it was observed that urinary Hg levels increased by 18% to 52% among 8 to 18 year old individuals, respectively, with an average exposur...
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a dose dependent relationship between mercury exposure from dental Amalgams and urinary mercury levels a further assessment of the casa pia children s dental Amalgam trial
Human & Experimental Toxicology, 2012Co-Authors: David A. Geier, Paul G King, Thomas J Carmody, Janet K Kern, Mark R. GeierAbstract:Dental Amalgams are a commonly used dental restorative material, and Amalgams are about 50% mercury (Hg). In our study, urinary Hg levels was examined in children of age 8-18 years, with and without dental Amalgam fillings, from a completed clinical trial (parent study) that was designed to evaluate the potential health consequences of prolonged exposure to Hg from dental Amalgam fillings. Our study was designed to determine whether there was a significant dose-dependent correlation between increasing Hg exposure from dental Amalgams and urinary Hg levels. Hg exposure depends on the size and number of teeth with dental Amalgams. Overall, consistent with the results observed in the parent study, there was a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental Amalgams and urinary Hg levels, after covariate adjustment. Further, it was observed that urinary Hg levels increased by 18% to 52% among 8 to 18 year old individuals, respectively, with an average exposure to Amalgams, in comparison to study subjects with no exposure to Amalgams. The results of our study suggest that dental Amalgams contribute to ongoing Hg exposure in a dose-dependent fashion.
Jose Maria Parmigianiizquierdo - One of the best experts on this subject based on the ideXlab platform.
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elevated systemic l kynurenine l tryptophan ratio and increased il 1 beta and chemokine cx3cl1 mcp 1 proinflammatory mediators in patients with long term titanium dental implants
Journal of Clinical Medicine, 2019Co-Authors: Jose Joaquin Merino, Maria Eugenia Cabanamunoz, Adolfo Toledano Gasca, Alba Garcimartin, Juana Benedi, Fabio Camachoalonso, Jose Maria ParmigianiizquierdoAbstract:Titanium is the mean biocompatible metal found in dental titanium alloys (Ti-6Al-4V). The safety of certain dental biomaterial Amalgams has been questioned in patients. The levels of several systemic cytokines (interleukin (IL)-1 beta, IL-4: pg/mL) and chemokines (monocyte chemoattractant protein-1 (MCP-1), soluble fractalkine (CX3CL1: pg/mL) were determined using ELISA and compared between these study groups. The study included 30 controls without dental materials (cont), 57 patients with long-term titanium dental implants plus Amalgams (A + I group) as well as 55 patients with long-term dental Amalgam alone (A group). All patients (except controls) have had dental titanium implants (Ti-6Al-4V) and/or Amalgams for at least 10 years (average: 15 years). We evaluated whether systemic levels of cytokines/chemokines, kyn/L-trp ratio and aromatic amino acid levels (HPLC: mM/L, Phe, L-Trp, His, Treo) could be altered in patients with long-term dental titanium and/or Amalgams. These systemic markers were evaluated in 142 patients. The A + I group had higher L-Kynurenine/L-Tryptophan ratios than patients with long-term dental Amalgam fillings alone (A). In addition, levels of IL-1 Beta cytokine, CX3CL1 and MCP-1 chemokines were higher in the A + I group than in the A group (A). The increased L-kyn/L-trp ratio and MCP-1 and fractalkine receptor (CX3CR1) elevations could suggest enhanced chemotactic responses by these chemokines in the A + I group.
Jacques Galland - One of the best experts on this subject based on the ideXlab platform.
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evaluation of the long term corrosion behavior of dental Amalgams influence of palladium addition and particle morphology
Dental Materials, 2003Co-Authors: Pierre Colon, Nelly Pradelleplasse, Jacques GallandAbstract:Abstract Objectives : The purpose of this investigation was to evaluate the long-term corrosion behavior of experimental Amalgams as a function of particle morphology and palladium content. Methods : Samples of four experimental high copper Amalgams were prepared according to ADA specifications. Two of them had the same chemical composition but one had lathe cut particles (LCP) and the other had spherical particles (SP). The two others had spherical powders with an addition of 0.5 wt% of palladium (SP 0.5) and 1 wt% of palladium(SP 1) for the other. Corrosion resistance was evaluated by electrochemical techniques in Ringer's solution in a thermostated cell at 37 °C for samples aged 5, 8, 12, 16 months and 10 years. Potentiokinetic curves were drawn and the potential and the current density corresponding to the first anodic peak were registered. Results : For all the Amalgam samples the corrosion behavior improves over the 10-year period. SP samples exhibit a better behavior than LCP. Palladium addition improves corrosion behavior as compared to samples without palladium. No real difference is found regarding the amount of palladium between 0.5 and 1%. The potentials progress from a range between 0 and 20 mV/SCE to a range of 60–80 after 10 years. The stabilization of the potential begins after only 16 months. Except for the LCP, all the values converge to the same level of 80 mV/SCE. Significance : The addition of no more than 0.5 wt% Palladium in a high copper Amalgam powder improves the corrosion behavior of the Amalgam up to a period of 10 years. The potential of the first anodic peak increases for each Amalgam, probably in relation to the evolution of the structure of the material. Clinically, it is of interest to consider the good electrochemical behavior of older restorations when contemplating the repair or replacement of such fillings. At the same time, galvanic current can occur when a new Amalgam restoration is placed in contact with an old one even if the same Amalgam is used. In this situation, the new filling will be anodic and its degradation will be accelerated. The evaluation of the corrosion behavior of dental Amalgams has to take into account the age of the samples.
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evaluation of the long term corrosion behavior of dental Amalgams influence of palladium addition and particle morphology
Dental Materials, 2003Co-Authors: Pierre Colon, Nelly Pradelleplasse, Jacques GallandAbstract:Abstract Objectives : The purpose of this investigation was to evaluate the long-term corrosion behavior of experimental Amalgams as a function of particle morphology and palladium content. Methods : Samples of four experimental high copper Amalgams were prepared according to ADA specifications. Two of them had the same chemical composition but one had lathe cut particles (LCP) and the other had spherical particles (SP). The two others had spherical powders with an addition of 0.5 wt% of palladium (SP 0.5) and 1 wt% of palladium(SP 1) for the other. Corrosion resistance was evaluated by electrochemical techniques in Ringer's solution in a thermostated cell at 37 °C for samples aged 5, 8, 12, 16 months and 10 years. Potentiokinetic curves were drawn and the potential and the current density corresponding to the first anodic peak were registered. Results : For all the Amalgam samples the corrosion behavior improves over the 10-year period. SP samples exhibit a better behavior than LCP. Palladium addition improves corrosion behavior as compared to samples without palladium. No real difference is found regarding the amount of palladium between 0.5 and 1%. The potentials progress from a range between 0 and 20 mV/SCE to a range of 60–80 after 10 years. The stabilization of the potential begins after only 16 months. Except for the LCP, all the values converge to the same level of 80 mV/SCE. Significance : The addition of no more than 0.5 wt% Palladium in a high copper Amalgam powder improves the corrosion behavior of the Amalgam up to a period of 10 years. The potential of the first anodic peak increases for each Amalgam, probably in relation to the evolution of the structure of the material. Clinically, it is of interest to consider the good electrochemical behavior of older restorations when contemplating the repair or replacement of such fillings. At the same time, galvanic current can occur when a new Amalgam restoration is placed in contact with an old one even if the same Amalgam is used. In this situation, the new filling will be anodic and its degradation will be accelerated. The evaluation of the corrosion behavior of dental Amalgams has to take into account the age of the samples.
David A. Geier - One of the best experts on this subject based on the ideXlab platform.
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New science challenges old notion that mercury dental Amalgam is safe
BioMetals, 2014Co-Authors: Kristin G Homme, Paul G King, Boyd E Haley, Lisa K Sykes, Janet K Kern, David A. Geier, Mark R. GeierAbstract:Mercury dental Amalgam has a long history of ostensibly safe use despite its continuous release of mercury vapor. Two key studies known as the Children’s Amalgam Trials are widely cited as evidence of safety. However, four recent reanalyses of one of these trials now suggest harm, particularly to boys with common genetic variants. These and other studies suggest that susceptibility to mercury toxicity differs among individuals based on multiple genes, not all of which have been identified. These studies further suggest that the levels of exposure to mercury vapor from dental Amalgams may be unsafe for certain subpopulations. Moreover, a simple comparison of typical exposures versus regulatory safety standards suggests that many people receive unsafe exposures. Chronic mercury toxicity is especially insidious because symptoms are variable and nonspecific, diagnostic tests are often misunderstood, and treatments are speculative at best. Throughout the world, efforts are underway to phase down or eliminate the use of mercury dental Amalgam.
-
evidence supporting a link between dental Amalgams and chronic illness fatigue depression anxiety and suicide
Neuro endocrinology letters, 2014Co-Authors: Janet K Kern, Paul G King, Kristin G Homme, Boyd E Haley, Lisa K Sykes, David A. Geier, Geir Bjørklund, Mark R. GeierAbstract:The purpose of this review is to examine the evidence for a relationship between mercury (Hg) exposure from dental Amalgams and certain idiopathic chronic illnesses - chronic fatigue syndrome (CFS), fibromyalgia (FM), depression, anxiety, and suicide. Dental Amalgam is a commonly used dental restorative material that contains approximately 50% elemental mercury (Hg0) by weight and releases Hg0 vapor. Studies have shown that chronic Hg exposure from various sources including dental Amalgams is associated with numerous health complaints, including fatigue, anxiety, and depression - and these are among the main symptoms that are associated with CFS and FM. In addition, several studies have shown that the removal of Amalgams is associated with improvement in these symptoms. Although the issue of Amalgam safety is still under debate, the preponderance of evidence suggests that Hg exposure from dental Amalgams may cause or contribute to many chronic conditions. Thus, consideration of Hg toxicity may be central to the effective clinical investigation of many chronic illnesses, particularly those involving fatigue and depression. Language: en
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a significant dose dependent relationship between mercury exposure from dental Amalgams and kidney integrity biomarkers a further assessment of the casa pia children s dental Amalgam trial
Human & Experimental Toxicology, 2013Co-Authors: David A. Geier, Paul G King, Thomas J Carmody, Janet K Kern, Mark R. GeierAbstract:Dental Amalgams are a commonly used dental restorative material. Amalgams are about 50% mercury (Hg), and Hg is known to significantly accumulate in the kidney. It was hypothesized that because Hg accumulates in the proximal tubules (PTs), glutathione-S-transferases (GST)-α (suggestive of kidney damage at the level of PT) would be expected to be more related to Hg exposure than GST-π (suggestive of kidney damage at the level of the distal tubules). Urinary biomarkers of kidney integrity were examined in children of 8–18 years old, with and without dental Amalgam fillings, from a completed clinical trial (parent study). Our study determined whether there was a significant dose-dependent correlation between increasing Hg exposure from dental Amalgams and GST-α and GST-π as biomarkers of kidney integrity. Overall, the present study, using a different and more sensitive statistical model than the parent study, revealed a statistically significant dose-dependent correlation between cumulative exposure to Hg fr...
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a dose dependent relationship between mercury exposure from dental Amalgams and urinary mercury levels a further assessment of the casa pia children s dental Amalgam trial
Human & Experimental Toxicology, 2012Co-Authors: David A. Geier, Paul G King, Thomas J Carmody, Janet K Kern, Mark R. GeierAbstract:Dental Amalgams are a commonly used dental restorative material, and Amalgams are about 50% mercury (Hg). In our study, urinary Hg levels was examined in children of age 8–18 years, with and without dental Amalgam fillings, from a completed clinical trial (parent study) that was designed to evaluate the potential health consequences of prolonged exposure to Hg from dental Amalgam fillings. Our study was designed to determine whether there was a significant dose-dependent correlation between increasing Hg exposure from dental Amalgams and urinary Hg levels. Hg exposure depends on the size and number of teeth with dental Amalgams. Overall, consistent with the results observed in the parent study, there was a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental Amalgams and urinary Hg levels, after covariate adjustment. Further, it was observed that urinary Hg levels increased by 18% to 52% among 8 to 18 year old individuals, respectively, with an average exposur...
-
a dose dependent relationship between mercury exposure from dental Amalgams and urinary mercury levels a further assessment of the casa pia children s dental Amalgam trial
Human & Experimental Toxicology, 2012Co-Authors: David A. Geier, Paul G King, Thomas J Carmody, Janet K Kern, Mark R. GeierAbstract:Dental Amalgams are a commonly used dental restorative material, and Amalgams are about 50% mercury (Hg). In our study, urinary Hg levels was examined in children of age 8-18 years, with and without dental Amalgam fillings, from a completed clinical trial (parent study) that was designed to evaluate the potential health consequences of prolonged exposure to Hg from dental Amalgam fillings. Our study was designed to determine whether there was a significant dose-dependent correlation between increasing Hg exposure from dental Amalgams and urinary Hg levels. Hg exposure depends on the size and number of teeth with dental Amalgams. Overall, consistent with the results observed in the parent study, there was a statistically significant dose-dependent correlation between cumulative exposure to Hg from dental Amalgams and urinary Hg levels, after covariate adjustment. Further, it was observed that urinary Hg levels increased by 18% to 52% among 8 to 18 year old individuals, respectively, with an average exposure to Amalgams, in comparison to study subjects with no exposure to Amalgams. The results of our study suggest that dental Amalgams contribute to ongoing Hg exposure in a dose-dependent fashion.
Jose Joaquin Merino - One of the best experts on this subject based on the ideXlab platform.
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elevated systemic l kynurenine l tryptophan ratio and increased il 1 beta and chemokine cx3cl1 mcp 1 proinflammatory mediators in patients with long term titanium dental implants
Journal of Clinical Medicine, 2019Co-Authors: Jose Joaquin Merino, Maria Eugenia Cabanamunoz, Adolfo Toledano Gasca, Alba Garcimartin, Juana Benedi, Fabio Camachoalonso, Jose Maria ParmigianiizquierdoAbstract:Titanium is the mean biocompatible metal found in dental titanium alloys (Ti-6Al-4V). The safety of certain dental biomaterial Amalgams has been questioned in patients. The levels of several systemic cytokines (interleukin (IL)-1 beta, IL-4: pg/mL) and chemokines (monocyte chemoattractant protein-1 (MCP-1), soluble fractalkine (CX3CL1: pg/mL) were determined using ELISA and compared between these study groups. The study included 30 controls without dental materials (cont), 57 patients with long-term titanium dental implants plus Amalgams (A + I group) as well as 55 patients with long-term dental Amalgam alone (A group). All patients (except controls) have had dental titanium implants (Ti-6Al-4V) and/or Amalgams for at least 10 years (average: 15 years). We evaluated whether systemic levels of cytokines/chemokines, kyn/L-trp ratio and aromatic amino acid levels (HPLC: mM/L, Phe, L-Trp, His, Treo) could be altered in patients with long-term dental titanium and/or Amalgams. These systemic markers were evaluated in 142 patients. The A + I group had higher L-Kynurenine/L-Tryptophan ratios than patients with long-term dental Amalgam fillings alone (A). In addition, levels of IL-1 Beta cytokine, CX3CL1 and MCP-1 chemokines were higher in the A + I group than in the A group (A). The increased L-kyn/L-trp ratio and MCP-1 and fractalkine receptor (CX3CR1) elevations could suggest enhanced chemotactic responses by these chemokines in the A + I group.
