Composite Fillings

What is composite filling, or a more common name "White fillings"?

A composite filling is the most common alternative filling to dental amalgam.  Composite filling made of acrylic resin, tooth-colored plastic, with silicon dioxide (powdered glass) reinforcement.

 Advantages of composite fillings include:

1. Aesthetic improvement with a broad range of tooth color, allowing minimally to no contrast between the filling and the tooth.
2. Least amount of tooth reduction
3. A material of choice to repair minimal damage to the tooth such as a chipped tooth
4. less time-consuming when use direct composite resin veneer to improve the smile
5. Strengthen the tooth structure through the bonding capability
 

Disadvantages of composite fillings include:

1. Less durable when compares to dental amalgam and may need frequent replacement
2. Higher fee
3. Color alteration in dark color environment such as coffee, tea
4. Post-operative sensitivity immediately after the composite filling
5. Time-consuming compares to amalgam filling
6. High shrinkage after curing created a marginal cavity. Select the low-shrinkage composite such as Heliomolar that has 2% shrinkage after 30 minutes of curing, may improve the result
7. The material and its component have their shelf life
8. Exposure to bisGMA-based dental composite restoration was found associated with impaired psychosocial function in children, according to the Journal of the American Academy of Pediatrics

Composition of Composite Fillings

Composite filling consists of:

1. Resin based matrix such as BISGMA (bisphenol A-glycidyl methacrylate) or UDMA (urethane dimethacrylate)
2. Inorganic filler such as silicon dioxide or engineered filler such as Glasses and glass-ceramics for wear and tear resistance and translucency
3. Coupling agent such as silane to enhance the bond between the filler and the matrix
4. Initiator such as camphor quinone (CQ), phenylpropanedione (PPD) or lucirin (TPO) begins the polymerization reaction of the resin after curing light is applied
5. Catalyst can control the speed of polymerization

How to place the composite fillings

Placement of direct composite filling:

1. Removes tooth decay and prepares the cavity
2. Applies etch bonding agent on the enamel surface
3. Places composite resin to the prepared cavity 
4. Uses curing light to polymerize (hardening) the filling or use a catalyst in self-cured composite resin to harden the resin.  
5. Shapes the composite filling, removes high spot and contours the filling  to blend in with the adjacent teeth
6. Immediately polishing the filling helps smooth the surface, reduce stain and minimize early wear of the filling.

Placement of indirect composite filling:
The filling itself is similar in color to the direct composite filling. The difference is the filling made in a dental laboratory by the certified dental technician and required two visits to the dental office.

First visit:

1. Removes tooth decay and prepares the cavity
2. Takes impression of the prepared tooth including adjacent teeth and opposing teeth
3. Sends impression to the laboratory to make an indirect filling
4. Place the temporary filling in the cavity to protect the tooth

Second visit:

1. Removes the temporary filling and clean the cavity
2. Examines the indirect filling for color, high spot, tightness of contact with adjacent tooth and adaptation to the prepared cavity
3. When every aspect of indirect filling is acceptable, it will be permanently cemented into the prepared cavity
4. Removes excessive cement around the margin
5. Re-checks for high spot and polishes the filling

Cavities close to gums, filled with composite fillings