Cracked Teeth!

The possible consequences of amalgam

Amalgam used to be the material of choice for fillings. Though they can last a long time and are hard wearing, they put a great deal of stress on the surrounding tooth structure.

  • Amalgam is metallic, with every bite, the force from above causes the metal to warp slightly
  • This force is transferred to the walls of the tooth around the filling
  • Over time cracks can form in the tooth - this is from 'Chronic Fatigue'
  • Treatment options vary depending on where and how a tooth cracks

1: Cracked Cusp

Symptoms (may include):

  • Temperature sensitivity – usually cold
  • Tenderness/pain on biting – especially hard foods eg. crusty bread
  • Chipped tooth – corner of tooth has fractured off

Treatment (may include):

  • Removal of remaining filling and replacement with composite resin or porcelain
  • Filling will replace cusp that has fracture off
  • Filling may cover cracked cusp to protect from further cracking

Example 1:

  • Sensitivity to cold, the indicated cusp was responsive when testing for cracks during a routine check up
  • Removal of amalgam revealed distinct crack underneath offending cusp
  • Restoration with composite resin to protect cracked cusp and prevent further cracks forming
  • Single appointment

Example 2:

  • Broken tooth/filling- very large, porcelain was chosen for its strength and durability
  • Amalgam was removed and prepared for a porcelain filling that would protect all cusps
  • Porcelain filling made by local dental technician A2 Dental Labs and colour matched to tooth
  • Porcelain then cemented onto tooth, restoring it aesthetically and providing support and protection
  • Two appointments 1 week apart

2: Cracked Cusp into Pulp

Symptoms (may include): Same as cracked cusp but more severe

  • Temperature sensitivity – heat
  • Pain on chewing – hard or soft foods
  • Spontaneous pain preventing and disrupting sleep

Treatment (may include):

  • Root Canal Treatment followed by restoration of tooth with:
    • Composite Resin
    • Porcelain Onlay
    • Crown (recommended for best long term outcome)
  • Extraction - there are options to replace the tooth including denture, bridge and implant

3: Split Tooth

Symptoms (may include):

  • Pain
  • Temperature sensitivity
  • Pain from any pressure
  • Movement from tooth or part of tooth

Treatment (may include):

  • Extraction – due to the severe nature of these splits it is generally not feasible to restore the tooth successfully
  • After extraction there are options to replace the tooth including denture, bridge and implant


  • Tooth broke, half of tooth mobile causing pain with any pressure
  • Tooth split vertically down to the level of the bone
  • Tooth was extracted and now awaiting complete healing for replacement of tooth with single tooth implant

Cracks in teeth are becoming more common due to the number of amalgams placed in the past. Some cracks remain harmless but some have distasterous consequences.

Cracks are unpredictable, they can occur anytime, in any tooth and we cannot predict when, where and how a tooth may crack.

If you have concerns about old large fillings, or if something doesn't feel right give us a call for a consult.

For further information please do not hesitate to contact us.

All images are original, consent has been gained for the use of any images of treatment performed here at Queen Street Dental.