Restoring Cavities with Dental Amalgam

Question 1

What is Amalgam?

Answer 1

An alloy of mercury with another metal

Question 2

What is the first stage in Class II Restoration Using Amalgam?

Answer 2

1.Outline Form

a) Gain access occlusally leaving sliver of enamel at margin
b) Using excavator or gingival margin trimmer, remove remaining enamel
c) Access can be gained to remove caries

Question 3

What is the second stage in Class II Restoration Using Amalgam?

Answer 3

2. Remove Caries

a) Remove caries, being sure to clear the contact area to the adjacent tooth to ensure that a matrix band can fit
b) Margins tidied, remove unsupported enamel, ensure that resistance and retention forms are included

Question 4

What is the third stage in Class II Restoration Using Amalgam?

Answer 4

Restore

a) Line as necessary
b) Place matrix band round the tooth, pack amalgam in cavity and carve back
c) Completed restoration

Question 5

What are the carving rules for amalgam?

Answer 5

• Carve back to the cavity outline.
• Removes Hg rich layer.
• Simulate lost anatomical form.
• Aim for a smooth amalgam/enamel junction.
• Do not reproduce deep fissures.
• Remove gross gingival excess.
• Always check that the restoration conforms to the patient’s occlusion.

Question 6

What is the The Bonded Amalgam Restoration advantages?

Answer 6

• Reduced need for preparation of retentive features in the cavity
• No need to use pins
• Reduced marginal leakage and postoperative sensitivity
• Reinforcement of tooth structure

Question 7

What is The Bonded Amalgam Restoration disadvantages?

Answer 7

• Time consuming
• More expensive than traditional amalgam restoration
• Lack of data on long –term clinical effectiveness

Question 8

What is the Bonded Amalgam Restorations technique?

Answer 8

1. Liner if appropriate
2. Acid etch margins
3. Apply prime and bond
4. Place ‘Rely–x– arc’ or ‘Smartcem’ (chemical cure resin-based cement) and leave uncured
5. Condense amalgam, carve etc.

Question 9

What are the amalgam toxicity side effects?

Answer 9

• Side effects are either toxic or allergic.
• Toxicity – mainly from mercury (Hg).
• Allergy – to any component – amalgam allergy may result in contact dermatitis, oral lichen planus etc.
• Theoretical risk of foetal damage as Hg can cross the placenta.

Question 10

What are Mercury Poisoning symptons?

Answer 10

• Headaches
• GI upsets
• Dyspepsia
• Tremors
• Salivation / xerostomia
• Severe gingivitis
• Fatigue / irritability
• Oedema of face and ankles
• Character changes

THERE IS NO CURE!!

Question 11

What are Safety Precautions When Handling Amalgam?

Answer 11

• Appropriate storage of waste amalgam
• Waste collected by approved contractor
• Well ventilated surgery
• Aspiration, venting externally with Hg removal filter