Background: Whether dental amalgam fillings (containing mercury) are hazardous is a long-standing issue, with few epidemiological investigations. Allegations have particularly involved nervous system disorders, such as multiple sclerosis, Alzheimer's disease, and chronic fatigue syndrome. This retrospective cohort study, the largest of its kind, contained people in the New Zealand Defence Force (NZDF) between 1977 and 1997. The NZDF has its own dental service, providing all personnel with regular and consistent treatment. Comprehensive treatment records are maintained and archived.

Methods: Yearly dental treatment histories, including amalgam filling placements, were compiled from individual records. To minimize amalgam exposure misclassification the cohort was restricted to people who, at NZDF entry, were aged <26 years and had all their posterior teeth. The cohort was linked with morbidity records. Data were analysed with a proportional hazards model, using a time-varying exposure unit of 100 amalgam surface-years.

Results: The final cohort contained 20 000 people, 84% males. Associations with medical diagnostic categories, particularly disorders of the nervous system and kidney, were examined. Of conditions allegedly associated with amalgam, multiple sclerosis had an adjusted hazard ratio (HR) of 1.24 (95% CI: 0.99, 1.53, P = 0.06), but there was no association with chronic fatigue syndrome (HR = 0.98, 95% CI: 0.94, 1.03), or kidney diseases. There were insufficient cases for investigation of Alzheimer's or Parkinson's diseases.

Conclusions: Results were generally reassuring, and provide only limited evidence of an association between amalgam and disease. Further follow-up of the cohort will permit investigation of diseases more common in the elderly.

Download full-text PDF

Source
http://dx.doi.org/10.1093/ije/dyh164DOI Listing

Publication Analysis

Top Keywords

dental amalgam
8
amalgam exposure
8
retrospective cohort
8
cohort study
8
health effects
4
dental
4
effects dental
4
amalgam
4
exposure retrospective
4
study background
4

Similar Publications

Mercury is a pervasive global pollutant, with primary anthropogenic sources including mining, industrial processes, and mercury-containing products such as dental amalgams. These sources release mercury into the environment, where it accumulates in ecosystems and enters the food chain, notably through bioamplification in marine life, posing a risk to human health. Dental amalgams, widely used for over a century, serve as a significant endogenous source of inorganic mercury.

View Article and Find Full Text PDF

Dental resin-based restorative (RBR) materials represent the most ubiquitous biomaterials utilized globally. Methacrylate (MA)-ester based monomers - present in RBRs since the 1960s - experience significantly elevated rates of failure compared to previously used silver/amalgam fillings attributed to their hydrolysis reported in both simulated and in vivo environments. There is currently no alternative RBR chemistry that matches the functional and clinical workflow considerations of MA-RBRs while addressing their limited-service lives.

View Article and Find Full Text PDF

Expression of beam hardening artifacts on horizontally stitched cone-beam computed tomography images.

Imaging Sci Dent

December 2024

Department of Oral Diagnosis, Division of Oral Radiology, Piracicaba Dental School, University of Campinas, Piracicaba, SP, Brazil.

Purpose: This study was performed to evaluate the expression of beam hardening artifacts generated by high atomic number materials in stitched cone-beam computed tomography (CBCT) images, compared to the traditional acquisition mode.

Materials And Methods: CBCT volumes were acquired using an acrylic resin phantom embedded with pairs of cylinders made from amalgam dental alloy, cobalt-chromium alloy, gutta-percha, titanium, and zirconium. These cylinders were placed within the overlapping zones of the stitching reconstruction area.

View Article and Find Full Text PDF

Identifying the sources of mercury exposure in dental workers.

Occup Med (Lond)

January 2025

Faculty of Medicine, Department of Preventive and Social Medicine, Chulalongkorn University, Bangkok 10330, Thailand.

Dental professionals who handle dental amalgam are at risk of mercury exposure, though the prevalence and severity of elevated mercury levels from non-occupational sources are not well characterized. We report two dental workers who had elevated urinary mercury levels (37 and 25.6 mcg/L) during routine health screenings.

View Article and Find Full Text PDF

Root-filling materials for endodontic surgery: biological and clinical aspects.

Biomater Investig Dent

October 2024

Section of Endodontics, Institute of Clinical Dentistry, Faculty of Dentistry, University of Oslo, Oslo, Norway.

The placement of root filling materials aims to prevent the occurrence of post-treatment apical periodontitis following completion of endodontic treatment. Materials should possess properties that will not permit bacterial invasion and infection, namely excellent sealing ability and/or antibacterial properties. In root-end filling procedures or repair of root perforations, the root filling materials are placed in a particularly challenging clinical environment, as they interface with a relatively large area with the periradicular tissues.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!