After diagnosing an issue and creating a treatment plan, the first step to restore a tooth to health is to ensure that you are comfortable. We will place some topical gel on the gum before we give you some local anaesthetic so that you do not feel any discomfort. After the decay or damage is prepared, the tooth is ready to receive either a direct restoration or an indirect restoration.
A direct restoration means that the tooth can likely be restored in one visit and that there is enough tooth structure for the filling to go inside of the tooth. Examples of direct restorations are amalgam, which is silver-colored; and composite; which is tooth coloured . Amalgams are not placed in our practice, due to environmental and health considerations.
1/ COMPOSITE RESIN RESTORATIONS
> tooth coloured fillings / white fillings / plastic fillings / resins
Composite resins are an approach to repairing broken teeth and cavities caused by tooth decay to look natural, match to the remaining teeth and restore health. Resin can be a good filling material when there is enough tooth structure to support it, but may wear out after about 5 years, and is technique sensitive. Our practice uses SonicFill 2 technology to restore the molar and premolar teeth. They are not designed for very large fillings in back teeth where there is little remaining tooth structure for the long term.
2/ 3D printed pressed porcelain restorations
An indirect filling means that the restoration is made outside of your mouth, either by a lab or by a milling machine which is cemented into place. Examples are crowns, inlays, and onlays. A crown covers the entire tooth, an inlay fits inside the tooth and can replace a wall of the tooth, and an onlay replaces at least one cusp of the tooth.
Two appointments are required and Swiss pressed porcelain is 3D printed, custom glazed and this is bonded seamlessly into the damaged section of the tooth. It is much stronger than composite resin fillings, and is strongest way to repair a damaged tooth with high aesthetic demands, and has been used for many years in veneers, inlays, onlays, and crowns
Matched perfectly to other teeth > aesthetics
Resistant to surface wear > strong
Long lasting > durable
Holds up well against chewing forces
Needs careful assessment to ensure that it is not going to undergo extreme forces from the bite
Requires two appointments > sent to a ceramist for 2 weeks
Gold restorations are a mixture of gold and other metals, to make them stronger.
You will need two appointments for a gold restoration. During the first visit, any decay or old filling material is removed, the tooth is prepared for the gold restoration, an impression is taken, and a temporary filling is placed.
The impression is then sent to the lab and a stone model is made, from which the lab makes a wax pattern, which is then cast into a gold restoration, within two weeks. When you return for your second appointment, the gold restoration is cemented into place.
Good resistance to further decay
Wears well because it has a similar hardness to enamel
Gold colour is undesirable for many patients
WHY AREN'T AMALGAM fillings PLACED?
Amalgam is a very forgiving and generally long lasting material. It is a tin, silver and mercury preparation that is very easily pressed into the cavity, and the corrosion products create a seal against bacteria entering the tooth. It expands and contracts with temperature changes, very differently to the supporting tooth structure, which can create stress fractures inside and on the outside of the tooth. Sometimes the cracks fatigue and a piece of tooth breaks off that previously supported the filling. If the crack is above the gum line, dentists term this a favourable fracture, meaning it can be restored. If the crack has reached the nerve of the tooth, bacteria can invade this area which must be kept sterile, and the tooth will die. To keep the tooth is an expensive and time consuming process, with root canal treatment (and crown work required for the back teeth). Usually amalgam will last for around 8 to 12 years and is particularly good for the very back teeth, and for mouths that have a high decay experience.
In 2019, we tend to remove amalgams and bond porcelain inlays and onlays into the damaged tooth. We tend to be conservative, and monitor amalgams for distortion, wear and defects, until there appears to be a problem. We shape and clean up the cavity, and leave as much tooth as possible. Generally the amalgam has caused discolouration into the tooth around the filling, after some years. An imprint of the cavity is sent to the technician, and porcelain is computer designed and milled. It is then custom glazed and matched exactly to the surrounding tooth by a master ceramist. We then bond this into the cavity. Porcelain inlays and onlays are extremely durable, biocompatible, incredibly strong and undetectable > everything that dentists could wish for for restorations of damaged teeth.