A Five-Year Follow-Up Study on the Removal of Dental Amalgam Restorations (Bergen Amalgam Trial): Examining Potential Confounding Factors and Effect Modification.
Lars Björkman, Frauke Musial, Terje Alræk, Harald J Hamre, Wolfgang Weidenhammer
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引用次数: 0
Abstract
Background: This government-funded project comprised experimental treatment aimed at improving health and quality of life for individuals with health complaints attributed to dental amalgam.
Objectives: The objective was to evaluate long-term changes in health complaints and health-related quality of life (HRQoL) after amalgam removal in individuals attributing health issues to dental amalgam, while also assessing effect modification and confounding factors.
Methods: The project was designed as a prospective cohort study. Three cohorts were followed over time: an Amalgam cohort (treatment group, n = 32), a cohort of patients with medically unexplained physical symptoms (MUPS cohort, n = 28) and a cohort of healthy volunteers (Healthy cohort, n = 19). The Amalgam cohort included patients with MUPS attributed to amalgam seeking amalgam removal, while the MUPS cohort had no such symptom attribution. Amalgam cohort participants had their fillings replaced with alternative materials. Questionnaires were completed at baseline (Q1), 1-year follow-up (Q2) and 4 years later (Q3). Changes over time were analysed using linear mixed-effects models.
Results: In the Amalgam cohort, general health complaints significantly decreased after amalgam removal, while HRQoL significantly improved. No major changes were observed over time in the other cohorts. The differences in change scores between the Amalgam and MUPS cohorts were statistically significant, indicating better health outcomes in the Amalgam cohort. Adjusting for potential confounders did not substantially alter the effect estimates. Stratified analyses suggested that baseline indicators of health might act as effect modifiers.
Conclusion: Improvement of health was consistent over time even after adjustment for potential confounders. Baseline indicators of health could be effect modifiers.
期刊介绍：
Journal of Oral Rehabilitation aims to be the most prestigious journal of dental research within all aspects of oral rehabilitation and applied oral physiology. It covers all diagnostic and clinical management aspects necessary to re-establish a subjective and objective harmonious oral function.
Oral rehabilitation may become necessary as a result of developmental or acquired disturbances in the orofacial region, orofacial traumas, or a variety of dental and oral diseases (primarily dental caries and periodontal diseases) and orofacial pain conditions. As such, oral rehabilitation in the twenty-first century is a matter of skilful diagnosis and minimal, appropriate intervention, the nature of which is intimately linked to a profound knowledge of oral physiology, oral biology, and dental and oral pathology.
The scientific content of the journal therefore strives to reflect the best of evidence-based clinical dentistry. Modern clinical management should be based on solid scientific evidence gathered about diagnostic procedures and the properties and efficacy of the chosen intervention (e.g. material science, biological, toxicological, pharmacological or psychological aspects). The content of the journal also reflects documentation of the possible side-effects of rehabilitation, and includes prognostic perspectives of the treatment modalities chosen.
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