What is a Dental filling made of?
What is a Dental filling made of?
Either a mercury-silver amalgam or a light-cured resin packed with glass — and the resin shrinks as it sets.
The main technical weakness of a composite filling is polymerisation shrinkage: the resin contracts by a couple of per cent as it cures, pulling at the bond to the tooth and opening microscopic gaps where decay can start again. That is why composites are placed in thin increments, each cured separately, and why a large composite takes far longer to place than an amalgam. Amalgam has been used for over 150 years and remains among the most durable options, but its mercury content led to the Minamata Convention phase-down, and many countries now restrict it, particularly for children and pregnant patients. The risk from placement and removal is to the environment and the dental workplace more than to the patient with an intact filling.
Component by component
| Part | Material | Why that material |
|---|---|---|
| composite matrix | Bis-GMA and urethane dimethacrylate monomers | They polymerise on demand under blue light, so the dentist can shape the filling for as long as needed and then set it in seconds. |
| composite filler | silane-treated glass, quartz or silica particles, 60-80% by weight | The glass provides wear resistance and stiffness; the silane coupling agent is what bonds it to the resin instead of letting it wash out. |
| photoinitiator | camphorquinone with an amine accelerator | It absorbs blue light around 470 nm and starts the polymerisation, which is the whole reason curing lamps are that colour. |
| amalgam | about 50% mercury alloyed with silver, tin and copper | It is cheap, self-sealing under load, tolerant of a damp field, and outlasts composite in large loaded cavities. |
| glass ionomer | a polyacrylic acid and fluoroaluminosilicate glass cement | It bonds chemically to tooth structure and releases fluoride, which is why it is used at the gum line and in children's teeth. |
Other medical and personal care objects
- Condom Dipped natural rubber latex, or synthetic polyisoprene or polyurethane for latex allergy — plus silicone lubricant.
- Surgical mask Three layers of polypropylene, of which only the electrostatically charged middle one does the filtering.
- Diaper (nappy) A superabsorbent polymer that holds many times its own weight in fluid, sandwiched between nonwoven plastic layers.
- Contact lens A water-swollen polymer gel — and the whole design problem is getting oxygen through it to the cornea.
- Tampon Compressed cotton, rayon or a blend, with a withdrawal cord and either a cardboard or plastic applicator.
- Eyeglass lens Almost never glass — usually CR-39, polycarbonate or a high-index plastic, under several thin coatings.
- Adhesive bandage (plaster) A plastic or fabric backing with pressure-sensitive adhesive, and a pad faced with a film that will not stick to the wound.
- Artificial hip A titanium or cobalt-chrome stem, a ceramic or metal ball, and a crosslinked polyethylene socket liner that is the wear surface.
- Syringe A polypropylene barrel and plunger with a rubber tip seal, and a stainless steel needle on a standard taper.
Common questions
- What is a Dental filling made of?
- Either a mercury-silver amalgam or a light-cured resin packed with glass — and the resin shrinks as it sets.
- What is the composite matrix of a Dental filling made of?
- Bis-GMA and urethane dimethacrylate monomers. They polymerise on demand under blue light, so the dentist can shape the filling for as long as needed and then set it in seconds.
- What is the composite filler of a Dental filling made of?
- Silane-treated glass, quartz or silica particles, 60-80% by weight. The glass provides wear resistance and stiffness; the silane coupling agent is what bonds it to the resin instead of letting it wash out.
Related pages
- Condom Dipped natural rubber latex, or synthetic polyisoprene or polyurethane for latex allergy — plus silicone lubricant.
- Surgical mask Three layers of polypropylene, of which only the electrostatically charged middle one does the filtering.
- Diaper (nappy) A superabsorbent polymer that holds many times its own weight in fluid, sandwiched between nonwoven plastic layers.
- Contact lens A water-swollen polymer gel — and the whole design problem is getting oxygen through it to the cornea.
- Tampon Compressed cotton, rayon or a blend, with a withdrawal cord and either a cardboard or plastic applicator.
- Eyeglass lens Almost never glass — usually CR-39, polycarbonate or a high-index plastic, under several thin coatings.
- Adhesive bandage (plaster) A plastic or fabric backing with pressure-sensitive adhesive, and a pad faced with a film that will not stick to the wound.
- Artificial hip A titanium or cobalt-chrome stem, a ceramic or metal ball, and a crosslinked polyethylene socket liner that is the wear surface.
- Pencil Stationery and paper
- Tennis ball Sport and games
- Banknote Around the house
- Golf ball Sport and games
- Paper Stationery and paper
- Glass Building materials
Sources
- Official vendor product documentation — At One Place