adam, Author at IAOMT Library

Systemic diseases caused by oral infection.

Recently, it has been recognized that oral infection, especially periodontitis, may affect the course and pathogenesis of a number of systemic diseases, such as cardiovascular disease, bacterial pneumonia, diabetes mellitus, and low birth weight. The purpose of this review is to evaluate the current status of oral infections, especially periodontitis, as a causal factor for systemic diseases. Three mechanisms or pathways linking oral infections to secondary systemic effects have been proposed: (i) metastatic spread of infection from the oral cavity as a result of transient bacteremia, (ii) metastatic injury from the effects of circulating oral microbial toxins, and (iii) metastatic inflammation caused by immunological injury induced by oral microorganisms. Periodontitis as a major oral infection may affect the host’s susceptibility to systemic disease in three ways: by shared risk factors; subgingival biofilms acting as reservoirs of gram-negative bacteria; and the periodontium acting as a reservoir of inflammatory mediators. Proposed evidence and mechanisms of the above odontogenic systemic diseases are given.

By Li X, Kolltveit KM, Tronstad L, Olsen I.|2018-07-25T18:17:22+00:00January 1st, 2000|Periodontal Disease|

Steady-state transfer and depletion kinetics of mercury from amalgam fillings.

In 29 volunteers with a low amalgam load, the number of amalgam-covered tooth surfaces and the occlusal area of the fillings were determined. Before and at select times after removal of all amalgams, concentrations of total mercury were measured by cold-vapor atomic absorption in plasma and erythrocytes as well as in urine together with the excretion rate. Absorbed daily doses were estimated from intraoral Hg emission by two separate methods. The transfer of Hg from the fillings via the oral cavity and blood to urinary excretion was evaluated according to the most representative combination of parameters. This consisted of occlusal area (1), absorbed dose (2), Hg concentration in plasma (3) and urinary excretion (4). Pairwise correlation coefficients were 0.49 for parameters 1 vs. 2, and 0.75 each for parameters 2 vs. 3 and 3 vs. 4. Within 9 days after removal of the fillings, a transient increase in Hg levels was observed in plasma only; in the group without a rubber dam, concentrations increased significantly above pre-removal values at days 1 and 3, whereas they decreased significantly below pre-removal values at day 30 in the rubber-dam group and at day 100 in both groups. Excretion rates decreased significantly at day 100 in the protected group. Peak plasma-Hg was 0.6 ng/ml on average at day 1 and decreased with halftimes of 3 and 43 days in subjects protected by a rubber dam. The results indicated that concentrations of total mercury in plasma responded rapidly to changes in the amalgam status and reflected the actual absorption most reliably. Notably, plasma-Hg levels were sensitive enough to detect a transient attenuation of the additional exposure after using a rubber dam during the removal of only a few fillings. However, being small in magnitude and lasting 100 days at best, the rubber-dam effect had minor toxicological relevance.

By Halbach S, Welzl G, Kremers L, Willruth H, Mehl A, Wack FX, Hickel R, Greim H.|2018-07-23T16:59:34+00:00January 1st, 2000|Mercury|

Association of silicofluoride treated water with elevated blood lead.

Previous epidemiological studies have associated silicofluoride-treated community water with enhanced child blood lead parameters. Chronic, low-level dosage of silicofluoride (SiF) has never been adequately tested for health effects in humans. We report here on a statistical study of 151,225 venous blood lead (VBL) tests taken from children ages 0-6 inclusive, living in 105 communities of populations from 15,000 to 75,000. The tests are part of a sample collected by the New York State Department of Children’s Health, mostly from 1994-1998. Community fluoridation status was determined from the CDC 1992 Fluoridation Census. Covariates were assigned to each community using the 1990 U.S. Census. Blood lead measures were divided into groups based on race and age. Logistic regressions were carried out for each race/age group, as well as above and below the median of 7 covariates to test the relationship between known risk factors for lead uptake, exposure to SiF-treated water, and VBL >10 microg/dL. RESULTS:
For every age/race group, there was a consistently significant association of SiF treated community water and elevated blood lead. Logistic regressions above and below the median value of seven covariates show an effect of silicofluoride on blood lead independent of those covariates. The highest likelihood of children having VBL> 10 microg/dL occurs when they are both exposed to SiF treated water and likely to be subject to another risk factor known to be associated with high blood lead (e.g., old housing). Results are consistent with prior analyses of surveys of children’s blood lead in Massachusetts and NHANES III. These data contradict the null hypothesis that there is no difference between the toxic effects of SiF and sodium fluoride, pointing to the need for chemical studies and comprehensive animal testing of water treated with commercial grade silicofluorides.

By Masters RD, Coplan MJ, Hone BT, Dykes JE.|2018-07-26T16:16:23+00:00January 1st, 2000|Fluoride|

Neuropathic pain in maxillofacial osteonecrosis.

Ischemic osteonecrosis (10) is not so much a disease in its own right as it is the natural consequence of a wide variety of systemic and local factors capable of compromising marrow blood flow (Table 1).1,9 It is the condition for which the term cavitation was coined in the orthopedic literature, and it is one of a select group of interrelated diseases able to deterio·rate and hollow out medullary spaces (Fig 1)1.10: First described in 1794 in a case of septic necrosis of the femoral head, this enigmatic disease is as old as the dinosaurs, but it has been poorly understood and has such subtle radiographic changes that until recently it was seldom diagnosed before end-stage damage. 1 ).13 Contemporary research has so enhanced our understanding of its basic pathophysiology that it now bears little resemblance to the entity once known as “aseptic osteomyelitis.”

By Bouquot JE, McMahon RE.|2018-08-25T00:37:35+00:00January 1st, 2000|Periodontal Disease|

Influence of periodontal infections on systemic health.

The influence of host factors on the pathogenesis and progression of periodontal diseases is widely recognized. Offenbacher (61) has reviewed the mechanisms by which physical, environmental and social host stresses affect and modify disease expression. Models of pathogenesis have been presented in which systemic disorders affecting neutrophil, monocyte and/or lymphocyte function result in altered production or activity of cytokines and inflammatory mediators.

By Mealey BL.|2018-08-28T00:18:46+00:00January 1st, 1999|Other|

Dental Restorations: How long do routine dental restorations last? A systematic review.

CONCLUSIONS:
Many studies were imperfect in design. Those considered to be the most appropriate for analysis were too limited to undertake a formal statistical exploration. Therefore there remains a need for definitive randomised controlled trials of restoration longevity, of sound design and adequate power, employing standardised assessments and appropriate methods of analysis.

By Downer MC, Azli NA, Bedi R, Moles DR, Setchell DJ.|2018-07-20T00:04:23+00:00January 1st, 1999|Mercury, Other|

Effect of rubber dam on mercury exposure during amalgam removal.

It was the aim of this investigation to treat 20 volunteers with maximally 5 amalgam fillings by the same comprehensive protocol in which all removals with (n = 8) and without (n = 12) rubber dam had been performed within a few months. Nine amalgam-related parameters indicated a close matching of both groups before removal. In the group without rubber dam, mercury (Hg) levels in plasma increased significantly above preremoval values at days 1 and 3 after removal; they decreased significantly below preremoval values at day 30 in the rubber-dam group and at day 100 in both groups. Excretion rates did not increase significantly in either group, but decreased significantly at day 100 in the protected group. Peak plasma-Hg was 0.6 ng/mL on average at day one and decreased with halftimes of 3 and 43 d in subjects protected by rubber dam. The results indicated that concentrations of total mercury in plasma responded rapidly to changes in the amalgam status and reflected the actual absorption most reliably. Notably, plasma-Hg levels were sensitive enough to detect a transient attenuation of the additional exposure by using rubber dam during the removal of only a few fillings. However, being small in magnitude and lasting 100 d at best, the rubber-dam effect had minor toxicological relevance.

By Kremers L, Halbach S, Willruth H, Mehl A, Welzl G, Wack FX, Hickel R, Greim H.|2018-07-24T23:52:09+00:00January 1st, 1999|Mercury|

Occupational exposure to mercury. What is a safe level?

QUESTION:
One of my pregnant patients, a dental hygienist, uses mercury in her workplace, but appears to have no symptoms of mercury toxicity. She has heard that mercury might affect her fetus. What should I recommend to her? What is a safe level of mercury in the air for pregnant women?

ANSWER:
Testing for levels of mercury in whole blood and, preferably, urine is useful for confirming exposure. Currently, mercury vapour concentrations greater than 0.01 mg/m3 are considered unsafe. Also, women of childbearing age should avoid contact with mercury salts in the workplace.

By Moienafshari R, Bar-Oz B, Koren G. .|2018-08-10T00:01:40+00:00January 1st, 1999|Mercury|

Water treatment with silicofluorides and lead toxicity.

Toxic metals like lead, manganese, copper and cadmium damage neurons and deregulate neurotransmitters like serotonin and dopamine (which are essential to normal impulse control and learning). Earlier studies show that — controlling for socio‐economic and demographic factors — environmental pollution with lead is a highly significant risk factor in predicting higher rates of crime, attention deficit disorder or hyperactivity, and learning disabilities. Exposure and uptake of lead has been associated with industrial pollution, leaded paint and plumbing systems in old housing, lead residues in soil, dietary habits (such as shortages of calcium and iron), and demographic factors (such as poverty, stress, and minority ethnicity). We report here on an additional “risk co‐factor” making lead and other toxic metals in the environment more dangerous to local residents: the use of silicofluorides as agents in water treatment. The two chemicals in question — fluosilicic acid and sodium silicofluoride — are toxins that, despite claims to the contrary, do not dissociate completely and change water chemistry when used under normal water treatment practices. As a result, water treatment with siliconfluorides apparently functions to increase the cellular uptake of lead. Data from lead screening of over 280,000 children in Massachusetts indicates that silicofluoride usage is associated with significant increases in average lead in children’s blood as well as percentage of children with blood lead in excess of 10μg/dL. Consistent with the hypothesized role of silicofluorides as enhancing uptake of lead whatever the source of exposure, children are especially at risk for higher blood lead in those communities with more old housing or lead in excess of 15 ppb in first draw water samples where silicofluorides are also in use. Preliminary findings from county‐level data in Georgia confirm that silicofluoride usage is associated with higher levels of lead in children’s blood. In both Massachusetts and Georgia, moreover, behaviors associated with lead nurotoxicity are more frequent in communities using silicofluorides than in comparable localities that do not use these chemicals. Because there has been insufficient animal or human testing of silicofluoride treated water, further study of the effect of silicofluorides is needed to clarify the extent to which these chemicals are risk co‐factors for lead uptake and the hazardous effects it produces.

By Masters RD, Coplan MJ.|2018-08-09T23:38:16+00:00January 1st, 1999|Fluoride|

Psychometric evidence that dental amalgam mercury may be an etiological factor in schizophrenia

Scores on the Minnesota Multiphasic Personality Inventory-2 (MMPI-2), the Million Clinical Multiaxial Inventory-II (MCM-II), and Symptom Check List – 90 (SCL-90) were compared before dental amalgam removal of eight schizophrenia patients to scores six months after amalgam removal. Significant improvement was found in forty-one of the sixty-one component scales of the MMPI-2 and twelve of the twenty subscales including schizophrenia, hysteria, paranoia, and anger. Sixteen of the twenty-five diagnostic scales improved significantly in the MCMI-II including schizoid, anxiety disorders, thought disorders, and bipolar symptoms. Four of nine dimensions improved significantly in the SCL-90 including depression, psychoticism, and obsessive-compulsiive. Because dental amalgam mercury can enter the brain and affect neurotransmitters, the authors hypothesize that removal of the mercury-laden fillings may have contributed to the improved mental health.

By Siblerud RL, Motl J, Kienholz E.|2020-04-01T22:17:47+00:00January 1st, 1999|Mercury|

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About Li X, Kolltveit KM, Tronstad L, Olsen I.