Wednesday, March 3, 2010

Composite Bonding

Dental bonding is a technique that has been used in cosmetic dentistry for many years and can transform your smile in just a single visit. The process involves the skilful/artistic use of the correct amount and colour of "dental composite", which is a mouldable material with a paste-like consistency made from acrylic resins and a variety of fillers, depending on the type used. Bonding is used for a variety of cosmetic dental procedures, including:

  • Filling dental cavities - "white fillings"
  • Replacing metal or amalgam fillings
  • Repairing broken and chipped teeth
  • Closing gaps between teeth (diastemas)
  • Reshaping teeth
  • Smile makeovers - composite veneers (although porcelain veneers are the better option for this)


Composite "white" fillings

Dental composite bonding is a popular choice for fillings because the material can match the shade, translucency and even the texture of your own natural teeth and provides a much better result than old amalgam/silver fillings, which can be unsightly when you smile. Cosmetic dentists often replace old metal fillings with tooth-coloured composite. There is much debate in dentistry as to the safety of mercury-containing amalgam fillings, and many dentists are of the opinion that metal fillings must be removed using a safe protocol, which involves isolating the teeth using a rubber dam material.

Can bonding be used for all cavities?

Bonding is not suitable if you have large cavities in your teeth, as the material does not have a strong structure over large areas. Bonding is ideal for small fillings that are not exposed to great forces. With recent advances indental technology, many dentists are turning to the use of CAD/CAM CEREC technology to produce ceramic fillings (inlays), which have the advantages of both strength and aesthetics and can be fitted in the same visit within an hour. Some practices may have their dental technicians fabricate a ceramic filling, which can take two to three weeks.

So what is the procedure of composite bonding?

If the procedure requires a local anaesthetic (not all bonding procedures do), your dentist will first numb the area by injecting a local anaesthetic into the gum area around the tooth. The tooth surface where the composite will be applied is thoroughly cleaned to remove any debris or tartar accumulation, as the composite needs a clean surface to bond to. Once the correct shade of composite has been selected by your dentist, the tooth is kept dry by surrounding it with cotton rolls or a latex sheet (rubber dam), and then shaped or roughened by the dentist using a special tool.

The surface of the tooth is then etched with a special phosphoric-acid-based gel, which provides a better surface for the composite to adhere to. The composite (bonding agent) is then applied to the etched tooth surface and exposed to a special light source (curing light), which activates the composite to harden and set. The bonding agent is often applied to the tooth in several thin layers (1mm-2 mm) until the desired shape, translucency and texture is achieved. The final step involves polishing and buffing the composite to give the desired shape and smooth finish.

What are the disadvantages of composite bonding?

The main drawbacks of bonding are that it doesn’t have the strength of other restorative materials such as ceramic or porcelain, and it has a greater tendency to stain than your surrounding natural teeth or porcelain.

Can any dentist carry out bonding?

Yes. However, you must note t hat bonding requires a high level of artistic skill and not all dentists are equally skilled. Some cosmetic dentists will have u ndertaken extensive postgraduate training in the field of dental bonding. Be sure to ask your dentist what experience he/she has in this area and if you can see photos of their previous work.

The term bonding is used in dentistry to describe permanently attaching dental materials to your teeth using dental adhesives and a high intensity curing light.

Whether you realize it or not, you've probably received a dental treatment involving either form of dental bonding: direct composite bonding or adhesive bonding of a restoration (crown, bridge, porcelain veneer, inlay/onlay) that was created in a laboratory or in-office.