Health Effects From Removal of Amalgam Restorations in Patients With Symptoms Allegedly Related to Dental Amalgam

Health Effects From Removal of Amalgam Restorations in Patients With Symptoms Allegedly Related to Dental Amalgam - A Study of Patients Examined at the Dental Biomaterials Adverse Reaction Unit in 1993 to 1999

Status

Completed

Phases

Phase 4

Study type

Interventional

Source

ClinicalTrials.gov

Registry ID

NCT00346944

Enrollment

Registered

2006-07-04

Start date

2002-09-30

Completion date

2010-03-31

Last updated

2012-08-28

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Adverse Effects, Dental Restoration, Permanent

Brief summary

The aim of the project is to study changes in symptom load after removal of all dental amalgam restorations in patients with symptoms allegedly related to amalgam.

Detailed description

Patients referred from dentists and physicians in the period 1993 to 1999 to the Dental Biomaterials Adverse Reaction Unit, Department of Health, UNIFOB AS, for symptoms related to amalgam restorations are randomized into treatment group (n=20) or reference group (n=20). All patients in the treatment group are followed 3, 12, 36 and 60 months after completion of amalgam removal with questionnaires on health outcomes, Minnesota Multiphasic Personality Inventory-2 (MMPI-2) and laboratory tests.

Interventions

PROCEDURERemoval of dental amalgam restorations

Removal of dental amalgam restorations by patient's own dentist. Fillings will be replaced with e.g. resin based filling material, metalloceramic restorations, and ceramic materials. Rubber dam will be used during removal of amalgam restorations.

Study design

Allocation

RANDOMIZED

Intervention model

FACTORIAL

Primary purpose

TREATMENT

Masking

NONE

Eligibility

Sex/Gender

ALL

Age

25 Years to 55 Years

Healthy volunteers

Inclusion criteria

* Referred for examination of general health complaints related to amalgam * Health complaints from at least three different organ systems * Dental amalgam restorations present * Data available on concentration of mercury in blood and urine at the initial examination * Patient agreed to be contacted after the examination

Exclusion criteria

* Serious disease (incl. severe allergy to foodstuff and severe rheumatoid arthritis) * Mental instability or psychiatric disease * Cases with complicated dental rehabilitation (incl. bridge prostheses) * Allergy to dental replacement materials * Severe periodontitis * High caries activity

Design outcomes

Primary

Measure	Time frame
Changes of subjective health complaints	Five years
Changes over time of the MMPI-profile	Five years
Quality of life improvement	Five years

Secondary

Measure	Time frame
Reduction of mercury in blood serum	One year

Countries

Norway

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026