Dental Fillings: Understanding Amalgam and Modern Alternatives

Dental Amalgam & Contemporary Restorative Materials

Dental amalgam is a stable alloy of mercury (≈50%), silver (~22–32%), tin (~14%), copper (~8%), and trace zinc. It has been used for >150 years due to durability, low cost, and ease of placement.

Modern Alternatives

Material	Composition	Indications	Pros	Cons
Composite resin	Bis‑GMA/UDMA matrix + silica/zirconia fillers	Anterior & posterior (small‑moderate)	Tooth‑colored, bonds to enamel/dentin, conservative prep	Technique‑sensitive, polymerization shrinkage, wear in high‑stress areas
Glass ionomer (GIC) / RMGIC	Fluoroaluminosilicate glass + polyacrylic acid	Cervical lesions, deciduous teeth, interim	Fluoride release, chemical adhesion, moisture tolerant	Lower strength, wear
Ceramic (inlay/onlay/crown)	Lithium disilicate, zirconia, feldspathic	Large defects, aesthetic zones	Excellent aesthetics, wear‑resistant, biocompatible	Lab/ CAD‑CAM required, higher cost, brittle
Gold alloy (cast)	High‑noble (Au, Pt, Pd)	Posterior inlays/onlays, bruxers	Unmatched longevity, marginal integrity, biocompatible	Cost, aesthetics, lab time

Amalgam Safety Consensus

• FDA, ADA, WHO: No credible evidence of systemic harm from amalgam mercury at current exposure levels.
• Minamata Convention: Phase‑down (not ban) – reduce use via prevention, alternatives, best practices.
• Contraindicated in mercury allergy (rare), pregnancy (precautionary), severe renal impairment.

Choosing a Material

Shared decision‑making: tooth location, extent, aesthetics, cost, longevity, patient preference, dentist’s expertise.