Dental Fillings: MMIs

This came up in one of my interviews.

How to fill a tooth

1. Patient put under local aesthetic
2. Drill/ air abrasion tool used to removed decayed area
3. Cavity is cleaned of bacteria and debris
4. Liner made of glass ionomer or composite resin may be placed if filling is near a root
5. Filling material placed an polished
6. For composite fillings, material is added in layers and hardened with light.

Pros and cons of different fillings

Gold

Pros

• Strong

• Does not corrode
• Aesthetics

Cons

• Expensive (10x more than amalgam)
• May require multiple visits
• Battery effect
• Allergen
• Aesthetics

Amalgam

Pros

• Does not corrode
• Easily placed
• Strong
• Somewhat cheap

Cons

• Aesthetics
• More invasive than others
• Discolouration of surrounding teeth
• Teeth may crack or fracture in the presence of hot and cold liquid
• Allergen
• Mercury vapour

Composite resin

Pros

• Aesthetics, similar to normal teeth
• Versatile- can be used for chipped teeth
• Less invasive

Cons

• Not as durable, easily chipped
• Increased chair time and visits
• Expensive
• Porcelain/ceramics
• More resistant to staining than composite
• Can be as expensive as gold

Glass ionomer

• Made from acrylic and glass
• Used for fillings below the gum line or in young children
• Releases fluoride
• Weaker than composite resin
• Weaker in general

Indirect fillings

• Used when there is not enough tooth structure to support the filling but the tooth is not that badly damaged such that it needs a crown
• Inlays
• Similar to fillings but lies within cusps
• Onlays
• Covers more than one cusp
• AKA partial crowns