Tooth Coloured Fillings

In the past when patients needed fillings placed in their back (chewing) teeth, dentists had few choices of materials for these fillings – either using silver amalgam or gold.  Because of the relatively low cost and ease of use amalgam has predominately been used.  Amalgam fillings are made of silver and other metals that are mixed with the mercury just prior to placement in the patient’s tooth.  Silver amalgam fillings serviced patients and dentistry well for decades.  However, the material does have its limitations and potential problems (as does any material used in dentistry):

  • Recent studies suggest that large silver amalgam fillings can contribute to the fracture of teeth.  Silver fillings contain mercury.  Mercury is used in thermometers because it expands and contracts with changes in temperature.  The mercury in silver amalgam fillings does the same thing.  This expansion and contraction of the silver filling causes stress in the tooth structure that surrounds the filling.  This stress can sometimes cause the tooth structure to fracture or break away from the tooth.
  • Over the years, the silver amalgam filling breaks down at the margin where the filling meets the tooth.  This break down of the metal causes the “seal” to be broken which allows decay causing bacteria to enter the area.
  • Silver amalgam fillings do not bond to tooth structure.  They are held in place by undercuts that the dentist has to make when preparing the tooth (drilling) for the restoration.  This means more tooth structure other than the decayed area has to be removed.  Also, when a filling is very large, the dentist may have to place reinforcement pins into the tooth in order for the filling to be held in place.
  • Silver amalgam fillings are unattractive, darken with age and cause discoloration of the teeth they are placed in.

What are the alternatives to silver amalgam fillings
With recent advances in dental material technology and bonding techniques, dentists have alternatives to placing silver amalgam fillings.  Two of these alternatives are Composite Bonding and Composite Inlays or Onlays.
Composite Bonding (Tooth Coloured Fillings)

What are the advantages of Composite Tooth Coloured Fillings ?

  • Tooth coloured bonded fillings are sealed to the tooth structure which prevents decay causing bacteria from infiltrating into the inner part of the tooth.
  • Composite bonding does not expand and contract with temperature changes, which could aid in preventing tooth fractures.
  • Many bonded fillings release fluoride in the tooth, which helps prevent recurrent decay.
  • Tooth coloured fillings look like natural teeth.

How is the procedure different from have silver amalgam fillings ?
In many cases, the procedure is very similar to having silver amalgam fillings.  The tooth or area is numbed with a strong anaesthetic solution.  The decay or old filling is removed and the tooth is prepared to accept the restoration.  Generally a smaller amount of tooth structure is removed when preparing for a tooth coloured filling.  The tooth is then “etched” with a special solution which roughens the enamel surface and allows the bonding material to adhere.  A shade of composite material is chosen that matches your natural tooth and is placed incrementally in layers into the tooth.  The dentist cures each layer of the material with a high intensity light which hardens and sets the material.  The filling is then trimmed to adjust to your bite and to achieve proper contour and shape.

How long will tooth coloured fillings last ?
How long any filling lasts depends on many factors.  Firstly, smaller fillings that are  surrounded by natural tooth structure will last much longer that large filings that are not surrounded and supported by natural tooth structure.  Secondly, how much biting pressure is exerted by the opposing teeth is also important.  Patients home care, frequency of visits and quality of diet are also factors that affect the longevity of fillings.  Tooth coloured fillings can last years before needing repair or replacement.

What are Composite Inlays or Composite Onlays ?
Composite Inlays or Onlays are tooth coloured fillings that are custom fabricated ina dental laboratory.  They are placed in teeth as replacements for silver amalgam fillings.  Composite Inlays and Onlays are bonded into both.

What advantages do they have over composite bonded fillings ?
If the silver restoration is very large, a composite inlay or onlay may be recommended over composite fillings because they are stronger.  Rather than merely filling your tooth, composite inlays or onlays form a strong bond that reinforces and protects weakened and vulnerable teeth.  These restorations are custom made in a dental laboratory and for this reason composite inlays/onlays are very aesthetic restorations that closely match the look of natural teeth.  The cosmetics results frequently exceed patients’ expectations.  Composite inlays or onlays have a high wear resistance, often outlasting many restorative materials.

What advantages to Composite Inlays or Onlays have over Crowns ?
When a tooth is prepared for a crown, a good deal of tooth structure has to be removed by the dentist in order to make room or space for the crown.  When a tooth is prepared for a composite inlay or onlay, only the old filling is removed and a very small amount of additional tooth structure is sacrificed.  More of your natural tooth structure is conserved when inlays or onlays are chosen.

How are Composite Inlays or Onlays done ?
This is a two visit procedure.  On the first visit, the area is made numb with a strong anaesthetic solution and the old silver filling and decay (if present) is removed.  The tooth is prepared for the inlay or onlay and an impression of the area is taken.  A temporary filling is placed in the tooth.  On the second visit, the temporary filling is removed and the composite inlay or onlay is fitted to the tooth prior to permanent placement.  When it meets your dentists’ satisfaction it is then bonded into place using a procedure similar to bonded composite fillings.  The inlay or onlay is then adjusted to the bite and polished.

Final Thoughts
In today’s’ world of modern dentistry, if you need to have a new filling (or an old one replaced) you have several choices as to the material that we can use.  These materials are much more aesthetic (natural) than some of the older materials, and are even stronger and possibly longer lasting.  Fillings don’t have to be visible.  Today there are great alternatives to silver amalgam fillings.  Composite bonded fillings, composite inlays /onlays allow patients and dentists a cosmetic and functional option.  They look, feel and function like natural teeth.  Our concern is your health, comfort and confidence.  Our goal is to help preserve your smile...for a lifetime !!!