Since our interim report of July 29, 1992, the Section of Epidemiology, Alaska. Department of Environmental Conservation (DEC), and United States Public Health Service (USPHS), have completed the investigation of the outbreak of fluoride poisoning in Hooper Bay.
A total of 142 women and 76 men with self-diagnosed oral galvanism who were referred from dentists and medical doctors for clinical evaluation during the last 2 yr are described from the perspective of general medicine. No case of clinically suspected mercury intoxication was found. Mean concentration of mercury in whole blood (B-Hg) was 17.3 nmol/l, and no value exceeded 50 nmol/l. Amalgam burden and B-Hg were not associated with clinical signs or symptoms except for a significantly lower mean value of B-Hg in patients with psychologic main symptoms than in those without (mean 15.4 vs. 18.1 nmol/l). It was possible to make one or several diagnoses in all 218 cases as reasonable alternatives to the concept of oral galvanism. Mental disorder was the main diagnosis in 93 cases (42.7%), including 41 cases of generalized anxiety disorder and 12 cases of panic disorder. A total of 87 patients (40%) did not work because of medical reasons or unemployment. Amalgam removal was recommended in a total of 65 cases (29%), mainly on psychologic indications, but in 22 cases because of oral conditions. The clinical conditions behind the concept of oral galvanism seem to be explicable in terms of general medicine, and no generalized toxic effect of amalgam fillings need be suspected.
The incidence of osteomyelitis of the jaws has decreased dramatically, except for a few subsets of individuals. This has been due, in no small part, to the availability of bacteriocidal antimicrobial therapy. The pathogenesis of osteomyelitis of the jaws is predominately due to odontogenic microorganisms rather than the classic skin contaminant, Staphylococcus. This causative relationship relegates the classification of osteomyelitis of the bimaxillary skeleton to predominately that of contiguous foci. These may be regionally progressive, secondary to microvascular compromise brought about by inherent flaws in regional anatomic calcified tissue vascular perfusion as well as by inflammatory metaplastic processes. Diagnosis is based on the presence of painful sequestra and suppurative areas of tooth-bearing jaw bone unresponsive to debridement and conservative therapy. This is usually accompanied by regional or systemic compromise of the immune response, microvascular decompensation, or both. Treatment of both acute and chronic forms of the disease, as outlined in Table 5, is successful if surgically supported. Sustained bacteriocidal antibiotic therapy is pertinent, especially in the face of potentially refractory virulent microorganisms and compromised regional vascular penetrance. The use of adjunctive hyperbaric oxygen therapy also may be included in the more refractory forms of osteomyelitis of the jaws to enhance the local and regional immune response of the jaws as well as to produce microvascular neoangiogenesis for reperfusion support. With resolution of infection, hard and soft tissue reconstruction may be necessary to augment the reparative process.
In this study was compared the mental health status of 47 multiple sclerosis patients with silver/mercury tooth fillings (amalgams) to that of 50 patients with their fillings removed. On the Beck Depression Inventory the multiple sclerosis subjects with amalgams suffered significantly more depression while their scores on the State-Trait Anger Expression Inventory indicated the former group also exhibited significantly more anger. On the SCL-90 Revised, subjects with amalgam fillings had significantly more symptoms of depression, hostility, psychotism, and were more obsessive-compulsive than the patients with such fillings removed. On a questionnaire containing 18 mental health symptoms multiple sclerosis subjects with amalgam fillings reported a history of 43% more symptoms than those without amalgam fillings over the past 12 months. These data suggested that the poorer mental health status exhibited by multiple sclerosis subjects with dental amalgam fillings may be associated with mercury toxicity from the amalgam.
Heavy metals are ingested in the diet or by inhalation. With ingestion of large amounts of heavy metals, or in disorders of excretion through liver, kidneys and intestines, they are stored in various repositories (e.g., central nervous system, bones, kidneys, liver, pancreas). They pass through the placenta and are likewise stored in fetal organs, where they are discernible partially in still higher concentrations than in the maternal organism. Dependent on time, amount and type of heavy metals, various symptoms and global effects can appear, which range from so-called psychosomatic disorders all the way up to severe poisonings with organic involvement. Because of the storability of heavy metals, the ability to demonstrate concentrations in the blood or urine is limited to acute poisonings. Yet chelators can effect release of heavy metal s from the repositories, which has been known already for decades in treatment of poisonings. And so the next step was to introduce, for a stimulation test, a chelator which has minimal unwanted side effects and yet is well suited to induce a safe heavy-metal excretion.
The disorder termed osteocavitation lesion has been described in the literature since at least 1976. This disorder has often been misdiagnosed as trigeminal neuralgia or atypical facial pain, and, unfortunately, patients have either continued to suffer or inappropriate treatment or treatments have been prescribed in an attempt to rid the patient of this terrible pain disorder. These symptoms, which can be misinterpreted as trigeminal neuralgia, include a history of undiagnosed facial pain, a history of tooth extraction, the presence of trigger areas and normal radiographic findings. A confirmed diagnosis of osteocavitation lesion can be treated only with surgery.
An in vitro method is described in which measurements were made of the total amount of mercury vapor released from three types of amalgam during routine dental procedures. It was found that the greatest amount of mercury was released during dry polishing of one amalgam (44 micrograms). Removal of amalgam from a Class I cavity under water spray and high volume evacuation also generated large amounts of mercury as expected (15-20 micrograms). However, under the more clinically relevant conditions of extending evacuation for one minute to remove residual amalgam and mercury after cutting, this value was reduced by approximately 90%. The total amount of mercury generated during placement (6-8 micrograms), wet polishing (2-4 micrograms) and trituration (1-2 micrograms) were also measured. The study showed that dental procedures associated with amalgam do potentially expose the patient and operator to mercury vapor. However, the total amount of mercury released during any procedure was far below the total exposure level calculated from the daily threshold limits established by regulatory agencies for occupational exposure.
The use of base metal alloys in dentistry has gained wide popularity in recent years. However, claims of their safety have not been universally accepted. An artificial oral environment capable of reproducing three-dimensional force-movement cycles of human mastication was used to determine whether nickel, chromium, and beryllium ions were leached from base metal alloy. Twelve pairs of crowns were articulated in the following combinations: metal versus metal, metal versus enamel, metal versus porcelain, and metal versus metal without chewing as a control. In a simulated 1-year period of mastication, the results showed that nickel and beryllium metals were released both by dissolution and occlusal wear. These findings suggest that if these conditions occur in the oral cavity, the stability of base-metal alloys is subject to question. Further studies are needed to determine whether the leaching reported has long-term consequences for patients receiving base metal restorations.
Mercury has several forms and produces subtle effects at chronic low-level exposures, mercury toxicity can be a difficult diagnosis to establish.
However, the effects on the central nervous system often appear after a long latency and remain long after the excretion in urine has dimished.