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Operative Dentistry

Dental Amalgam

(Last updated: August 13, 2014)

Dispersalloy Megalloy EZ

(Dentsply Caulk) stocked
self-activating blue capsules (600 mg)

Description:  A slower setting, admixed (mixture of lathe-cut rods and silver-copper spheres), high-copper alloy used for large restorations and foundations and when obtaining proximal contact or proper contours may be difficult.

Condensation time 3 ½ min.
Set time 4 ½ min.

(Dentsply Caulk) stocked
self-activating purple capsules (600 mg)

Description:  A fast setting, spherical high-copper alloy used for small and moderate sized restorations.

Condensation time 3 min
Set time: 2 to 3 ½ min.


  • General trituration guidelines:
    Manufacturer’s variation in amalgamators and differences in local electrical current may necessitate adjusting trituration time.
    Over mixing: May result in a dry but coherent mass that sticks in the capsule, may feel hot and sets too fast, DISCARD.
    Under mixing: May result in a dry and crumbly mix, DISCARD.
    Ideal mixing: A cohesive plastic mass that loads easily in carrier and condenses well.
Amalgamator Dispersalloy
Double spill (600mg)
Megalloy EZ
Double spill (600 mg)

Kerr Optimix & Automix

3800cpm 14 ±3s

4000cpm 10-13s

Caulk Promix

Turtle 14 ±3s

Rabbit 7-9s or Turtle 12-15s

  • Admixed alloy condensation guidelines (Dispersalloy):  Use small-faced condensers to apply adequate condensation force (5 to 10 lbs.) to increments placed 1mm or less in thickness.  Adequate force may cause a slight movement of the patient’s mandible or head.  For all amalgams, a large condenser should be used for the overfilling of the preparation.
  • Spherical alloy condensation guidelines (Megalloy EZ):  Require less condensation force; in general, use the largest condenser that fits in the area of interest and use both a vertical and a lateral packing technique.  This may require small-faced condensers for angles and undercuts before use of larger condenser.  It is somewhat more difficult to obtain good interproximal contact with spherical amalgams than with lathe-cut amalgams or admixtures.