Decrease of trace elements in erythrocytes and plasma after removal of dental amalgam and other metal alloys

Reference intervals of 24 trace elements in blood, plasma and erythrocytes for the Slovenian adult population

OBJECTIVES

The aim of the present study was to establish the population- and laboratory-specific reference intervals (RIs) for the Slovenian adult population for 24 trace elements (TEs) in blood, plasma and erythrocytes and to evaluate the impact of gender, age, seafood consumption, smoking habits and amalgam fillings on TEs levels.

METHODS

TEs (Mn, Co, Cu, Zn, Se and Mo, Li, Be, V, Cr, Ni, Ga, As, Rb, Sr, Ag, Cd, Sn, Cs, Au, Hg, Tl, Pb and U) were determined in 192 a priori selected blood donors (107 women and 85 men, aged 18-65 years), using inductively coupled plasma mass spectrometry (ICP-MS) with the Octopole Reaction System. Participants filled out a questionnaire, and RIs were established according to the Clinical and Laboratory Standards Institute (CLSI) guidelines for TEs.

RESULTS

Uniform RIs for non-essential and gender-specific for essential TEs in blood, plasma and erythrocytes were established. In our population, higher blood and plasma Cu, and erythrocyte Mn levels in women were found. In men, blood Zn, plasma Zn, Mn and Se, and erythrocyte Cu levels were higher. Zn levels were higher in 30-39 years age group. Pb and Sr increased with age. Smoking positively affected Cd, Pb, Cs and Rb; seafood consumption increased As, Hg and Zn; and amalgam increased Hg, Ag and Cu levels.

CONCLUSIONS

Essential TEs were inside recommended levels, and the non-essential ones were far below critical levels. Established RIs will provide an important foundation for clinical diagnostics, safety erythrocyte transfusions assessment, toxicology and epidemiological studies.

Mercury, silver and selenium in serum before and after removal of amalgam restorations: results from a prospective cohort study in Norway

OBJECTIVE

A prospective cohort study on changes of health complaints after removal of amalgam restorations was carried out at the request of the Norwegian Directorate of Health. The aim was to provide and evaluate experimental treatment to patients with health complaints attributed to dental amalgam fillings.

METHODS

Patients (n = 32) with medically unexplained physical symptoms (MUPS), which were attributed to dental amalgam restorations had all their amalgam restorations removed and replaced with other dental restorative materials. Samples of blood were collected before and 1 year after removal of the fillings, and concentration of inorganic mercury (I-Hg), methylmercury (MeHg), silver (Ag) and selenium (Se) in serum was determined by inductively coupled plasma-sector field mass spectrometry. The comparison groups (one with MUPS but without attribution to amalgam [n = 28] and one group of healthy individuals [n = 19]) received no treatment. The participants responded to questionnaires at baseline and at follow-up after 1 and 5 years.

RESULTS

Concentration of I-Hg and Ag in serum decreased significantly after removal of all amalgam restorations. Concentration of MeHg and Se in serum were not changed. Intensity of health complaints was significantly reduced after amalgam removal, but there were no statistically significant correlations between exposure indicators and health complaints.

CONCLUSIONS

Removal of all amalgam restorations is followed by a decrease of concentration of I-Hg and Ag in serum. The results support the hypothesis that exposure to amalgam fillings causes an increase of the daily dose of both I-Hg and Ag. Even though intensity of health complaints decreased after removal of all amalgam restorations there was no clear evidence of a direct relationship between exposure and health complaints. Trial registration: The project is registered at Clinicaltrials.gov (NCT01682278).

Apparent Surface Free Energy of Polymer/Paper Composite Material Treated by Air Plasma

Surface plasma treatment consists in changes of surface properties without changing internal properties. In this paper composite polymer/paper material is used for production of packaging in cosmetic industry. There are problems with bonding this material at the time of packaging production due to its properties. Composite surface was treated by air plasma for 1, 10, 20, and 30 s. The advancing and receding contact angles of water, formamide, and diiodomethane were measured using both treated and untreated samples. Apparent surface free energy was estimated using the hysteresis (CAH) and Van Oss, Good, Chaudhury approaches (LWAB). Surface roughness was investigated using optical profilometry and identification of after plasma treatment emerging chemical groups was made by means of the XPS (X-ray photoelectron spectroscopy) technique. After plasma treatment the values of contact angles decreased which is particularly evident for polar liquids. Apparent surface free energy increased compared to that of untreated samples. Changes of energy value are due to the electron-donor parameter of energy. This parameter increases as a result of adding polar groups at the time of surface plasma activation. Changes of surface properties are combination of increase of polar chemical functional groups, increase on the surface, and surface roughness increase.

Health Complaints Attributed to Dental Amalgam: A Retrospective Survey Exploring Perceived Health Changes Related to Amalgam Removal

BACKGROUND

Many patients have complex health complaints they attribute to dental amalgam. There is some evidence of symptom relief after removal of amalgam.

OBJECTIVE

The aims of this study were to assess the total symptom load in patients with all their amalgam fillings removed, and to investigate the self-reported improvement of health with regard to precautions taken under amalgam removal and time since removal.

METHODS

The survey was distributed to all members (n=999) of the Norwegian Dental patients association in 2011. The study participants returned the questionnaires anonymously by means of a pre-stamped envelope. The questionnaire asked for sociodemographic data, subjectively perceived health status, complaints persisting after amalgam removal and self-reported changes in symptoms after amalgam removal.

RESULTS

A total of 324 participants were included in the study. The majority of the participants reported improved health after amalgam removal, even though the mean degree of severity of complaints was still high. Exhaustion and musculoskeletal complaints were most severe, and reflects the fact that 38% of the participants reported poor to very poor current health. With regard to amalgam removal, associations between improved health, number of precautions applied, and time since removal were found.

CONCLUSION

Most of the participants in this study reported improvement of health after amalgam removal even though they still suffered a high complaint load. Since absolute symptom load is a robust predictor for general health outcome and socioeconomic burden for society, a possible intervention, which enables patients to further improve their health status is desirable.

Release of metal ions from orthodontic appliances: an in vitro study

In this paper, we report the results of an in vitro experiment on the release of metal ions from orthodontic appliances composed of alloys containing iron, chromium, nickel, silicon, and molybdenum into artificial saliva. The concentrations of magnesium, aluminum, silicon, phosphorus, sulfur, potassium, calcium, titanium, vanadium, manganese, iron, cobalt, copper, zinc, nickel, and chromium were significantly higher in artificial saliva in which metal brackets, bands, and wires used in orthodontics were incubated. In relation to the maximum acceptable concentrations of metal ions in drinking water and to recommended daily doses, two elements of concern were nickel (573 vs. 15 μg/l in the controls) and chromium (101 vs. 8 μg/l in the controls). Three ion release coefficients were defined: α, a dimensionless multiplication factor; β, the difference in concentrations (in micrograms per liter); and γ, the ion release coefficient (in percent). The elevated levels of metals in saliva are thought to occur by corrosion of the chemical elements in the alloys or welding materials. The concentrations of some groups of dissolved elements appear to be interrelated.

Cytocompatibility of medical biomaterials containing nickel by osteoblasts: a systematic literature review

The present review is based on a survey of 21 studies on the cytocompatibility of medical biomaterials containing nickel, as assessed by cell culture of human and animal osteoblasts or osteoblast-like cells. Among the biomaterials evaluated were stainless steel, NiTi alloys, pure Ni, Ti, and other pure metals. The materials were either commercially available, prepared by the authors, or implanted by various techniques to generate a protective layer of oxides, nitrides, acetylides. The observation that the layers significantly reduced the initial release of metal ions and increased cytocompatibility was confirmed in cell culture experiments. Physical and chemical characterization of the materials was performed. This included, e.g., surface characterization (roughness, wettability, corrosion behavior, quantity of released ions, microhardness, and characterization of passivation layer). Cytocompatibility tests of the materials were conducted in the cultures of human or animal osteoblasts and osteoblast-like cells. The following assays were carried out: cell proliferation and viability test, adhesion test, morphology (by fluorescent microscopy or SEM). Also phenotypic and genotypic markers were investigated. In the majority of works, it was found that the most cytocompatible materials were stainless steel and NiTi alloy. Pure Ni was rendered and less cytocompatible. All the papers confirmed that the consequence of the formation of protective layers was in significant increase of cytocompatibility of the materials. This indicates the possible further modifications of the manufacturing process (formation of the passivation layer).

Release of metal ions from orthodontic appliances by in vitro studies: a systematic literature review

In the present work, a systematic literature review on release of metal ions from orthodontic appliances under in vitro conditions is described. Detailed and schematic analysis of used materials and applied methods (immersion media, incubation time, temperature, and analytical techniques) is provided. The PubMed search identified 40 studies, among which eight met the selection criteria. One additional study was included in the review. All the authors agreed that the doses of released metal ions were far below the toxic level and the dietary intake. Although the concentrations of metal ions in immersion media greatly differed, the general conclusions were coherent. It must be underlined that the main disadvantage of in vitro tests was that the experimental setup did not reflect in vivo conditions, e.g., the presence of biofilm, which grows on the surface of the materials in oral cavity. The presence and activity of microflora to a large extent is responsible for the process of corrosion, in particular, biodeterioration. The further scheme of in vitro research should incorporate changeable conditions of oral cavity environment (pH, dynamic conditions-saliva flow) and the presence of microbiological flora (microbiological attack) in the experimental design and, first of all, the real proportions of appliance elements.

Thoracic aortic aneurysm patients with Chlamydophila pneumoniae infection showed a shift in trace element levels in serum and diseased aortic tissue

Few studies have been performed on trace elements in tissues and serum in cardiovascular disease and none in aortic aneurysm. In this study the concentrations of 10 trace elements were determined in serum and aneurysmatic aortic tissue from 23 patients undergoing thoracic surgery. Macroscopically, normal thoracic aortic tissue specimens from 10 forensic autopsies and serum from 23 healthy blood donors served as controls. DNA from the intracellular respiratory pathogen Chlamydophila pneumoniae (C. pneumoniae), which may be involved in the pathogenesis of atherosclerosis, was found in 26% (6/23) of the patients but in none of the controls. The serum copper/zinc ratio, a well-known marker of ongoing infection and/or inflammation, was higher (26%, p<0.001) in aneurysm patients. C. pneumoniae requires iron for its growth. In our aneurysm patients iron was higher in serum (by 54%, p<0.001) and aneurysmal tissue (by 60%, p<0.001). Although calcium was lower in patient sera (by 8%, p<0.001), it tended to be higher (by 20%, ns) in aneurysmatic tissue. In addition, mercury concentrations in serum and aneurysmatic tissue were positively correlated (r=0.51, p<0.05). Moreover, C. pneumoniae-positive aneurysmatic tissues had lower concentrations of manganese (46%, p<0.05) and zinc (26%, ns) but a higher concentration of mercury (50%, p<0.05) than C. pneumoniae-negative aneurysmatic tissues. In conclusion, aneurysm patients showed a shift in trace element levels in serum and in the diseased part of the aorta, the pattern being partly different in C. pneumoniae-positive compared with C. pneumoniae-negative patients. The results are compatible with active infection and/or inflammation, possibly initiated by C. pneumoniae.

Cellular immunity impaired among patients on left ventricular assist device for 6 months

BACKGROUND

Sustained maintenance on left ventricular assist device (LVAD) is associated with an increased frequency of severe infections. Although temporary changes in cellular immunity are seen immediately after implantation, the consequence of sustained LVAD treatment on immunity is unknown.

METHODS

In vitro functional and phenotypic markers of T cell activation and 6 month clinical outcome were compared between patients with > or = 6-month LVAD therapy and heart failure control patients.

RESULTS

Recipients of LVADs had more infections (45.5% versus 0%; p < 0.05) and mortality (54% versus 16%; p < 0.05) than control patients. T-cell proliferative responses were lower among LVAD recipients than control patients when challenged with phytohemagglutinin (3.4 +/- 4.7 versus 28.5 +/- 19.6; p < 0.01), anti-CD3 (4.3 +/- 4.5 versus 16.4 +/- 17; p < 0.01), and staphylococcal enterotoxin B (7.2 +/- 6.3 versus 26.1 +/- 15.6; p = 0.002). Proliferative hyporesponsiveness among LVAD recipients was not caused by apoptosis (2.6% +/- 2.7% versus 2.7% +/- 2.1%; p = 0.94) or insufficient CD4+ cells (42.1% +/- 11.3% versus 40.2% +/- 7.5%; p = 0.71) relative to control patients. Instead, CD3+ cells from LVAD patients expressed less interleukin 2 (2.5% +/- 1.5% versus 5.2% +/- 3.1%; p = 0.03) and tumor necrosis factor-alpha (6.0% +/- 3.5% versus 25.8% +/- 8.7%; p < 0.001) and more interleukin 10 (5.8% +/- 6.1% versus 2.6% +/- 2.1%; p < 0.05). In addition, suppressive T-regulatory cells were more prevalent in LVAD patients than control patients (12.9% +/- 3.2% versus 1.2% +/- 1.1%; p < 0.001).

CONCLUSIONS

Cellular immunity is compromised among long-term LVAD recipients because of a downregulatory cytokine imbalance and emergence of suppressive T-regulatory cells.

Changed clinical chemistry pattern in blood after removal of dental amalgam and other metal alloys supported by antioxidant therapy

This study aimed to investigate a possible connection between removal of dental amalgam restorations supported by antioxidant therapy and indicative changes of clinical chemistry parameters. A group of 24 patients, referred for complaints related to amalgam restorations, underwent a removal of their amalgams. All patients were treated with antioxidants (vitamin B-complex, vitamin C, vitamin E, and sodium selenite). An age- and sex-matched control group of 22 individuals was also included. The mercury (Hg) and selenium (Se) concentration in plasma, Hg concentration in erythrocytes, and 17 clinical chemistry variables were examined in three groups: patients before amalgam removal (Before), patients after amalgam removal (After), and control individuals (Control). The Hg and Se values decreased (p < 0.05) in plasma, and the Hg concentration decreased (p < 0.05) in erythrocytes after amalgam removal. The variables serum lactate dehydrogenase (serum LDH) and serum sodium differed significantly both when comparing Control with Before (p < 0.01) and Before with After (p < 0.01). The variables white blood cell count (WBC), blood neutrophil count, blood eosinophil count, blood basophil count, blood lymphocyte count, blood monocyte count, serum potassium, and serum creatinine differed in the Before/After test (p < 0.05). Multivariate statistics (discriminant function analysis) could separate the groups Before and After with only one misclassification.