Removal of dental amalgam restorations in patients with health complaints attributed to amalgam: A prospective cohort study

Abstract

Summary Background The Norwegian Ministry of Health and Care Services initiated a project including experimental treatment for patients with health complaints attributed to amalgam restorations. Objective The aim was to evaluate changes of general health complaints in patients who participated in the project and had all amalgam restorations removed. Methods The project was designed as a prospective cohort study and organised by the Dental Biomaterials Adverse Reaction Unit in Bergen, Norway. The dental treatment was provided by the patient's local dentist. The main target group consisted of patients with medically unexplained physical symptoms, attributed to dental amalgam restorations (Amalgam cohort). The primary comparison group consisted of patients with medically unexplained physical symptoms without attribution to dental amalgam restorations (MUPS cohort). Primary outcome was self‐reported general health complaints (GHC index) at follow‐up 12‐months after completed amalgam removal. Results In the Amalgam cohort, a significant reduction of GHC index from 43.3 (SD 17.8) at baseline to 30.5 (SD 14.4) at follow‐up (mean reduction 12.8, SD 15.9; n = 32; P < .001) was observed. The change scores for GHC index indicated that the reduction of complaints was significantly higher (P = .004) in the Amalgam cohort compared with the MUPS cohort (mean reduction 1.2, SD 12.3, n = 28). After adjustment for age, gender, education and baseline GHC index, the mean adjusted difference was −8.0 (95% confidence interval from −15.4 to −0.5; P = .036). Conclusion In a group of patients with medically unexplained physical symptoms, which they attributed to dental amalgam restorations, removal of amalgam restorations was followed by a significant reduction of health complaints.

Validity and responsiveness of EQ-5D-5L and SF-6D in patients with health complaints attributed to their amalgam fillings: a prospective cohort study of patients undergoing amalgam removal

“…The analyses are based on data from a prospective cohort in Norway [45]. The study comprised three groups recruited separately: (i) patients with MUPS, which they attributed to dental amalgam restorations who wished to have their amalgam fillings removed (Amalgam cohort); (ii) patients with MUPS recruited from general practice without symptom attribution to amalgam fillings (MUPS cohort); and (iii) participants who identified themselves as healthy (Healthy cohort).…”

“…Other inclusion criteria were unspecific health complaints attributed to dental amalgam restorations at least for three months, wish to have all amalgam fillings removed, ability to comply with the protocol, age between 20 and 70 years, permanent residence in Norway. Detailed eligibility criteria and recruitment procedures are reported elsewhere [45]. In general, a total of 49 participants were initially assessed for inclusion in the Amalgam cohort.…”

Validity and responsiveness of GHC-index in patients with amalgam-attributed health complaints

“…Some patients with MUPS attribute their health complaints to dental amalgam restorations. In this patient group, there is some evidence of symptom relief after removal of amalgam [14,15]. Among MUPS symptoms, neurological symptoms such as fatigue and dizziness are the most reported complaints attributed to dental amalgam [16].…”

“…Thus, a total of 32 participants were available for the follow-up analysis. Detailed recruitment procedures and eligibility criteria were reported elsewhere [14,22].…”

“…Pain in muscles and joints, and headache as well as gastrointestinal symptoms are also commonly reported [17]. A General Health Complaints index (GHC-index), which includes common general health complaints in patients referred to the Norwegian Dental Biomaterials Adverse Reactions Unit, has widely been used in Norway [14,15,18,19]. The GHC-index was intended to capture these major symptoms, but its validity and responsiveness have so far not been formally investigated.…”