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Whangarei Dental Fillings

Used to prevent the spread of tooth decay or correct any cosmetic damage, a filling is just one of the ways our dentists preserve your health. Before placement, any decay must be removed. We use local anaesthesia to ensure maximum comfort for our patients. There are two different types of fillings: Amalgam (otherwise known as silver fillings) and Composite, the colour of which will be customised to match your natural teeth.



Amalgam fillings are made up of a mixture of metals. They typically contain about 50 percent mercury, along with tin, copper, silver or zinc. Compared to other types, amalgam fillings have one thing going for them - they're very strong and typically longer-lasting.

Amalgam fillings aren't without drawbacks, though. They're silver in color to start and tend to become darker with time, meaning they are fairly conspicuous when you open your mouth. And although it's been determined that the level of mercury in this type of filling is safe for people over the age of six, you might prefer not to have a filling made from this material.



A composite tooth filling, typically made of powdered glass and acrylic resin, offers a few advantages over an amalgam filling. For one, the filling can be shaded to match the colour of your existing teeth, making it much less visible. As more people want natural-looking smiles and are becoming more concerned about the mercury in amalgam fillings, composite fillings have become increasingly popular.

Our experienced staff will help you by providing the best possible treatment for Whangarei Dental Fillings. Contact us today.



What is a filling?

A filling is a dental restoration used to occupy missing areas of a tooth from decay, trauma or wear. Dental fillings do just what the name implies, fill a space. Small to medium sized areas of a tooth can be successfully restored using dental fillings. However, large missing areas of a tooth require more extensive treatment such as a crown, onlay or veneer.

Why do I need a filling?

The most common need for a filling is due to decay. However, a filling can sometimes be used to replace a broken piece of a tooth, change the colour of teeth, or build up a tooth that has been lost due to wear.

Tooth decay is the primary reason fillings are placed in teeth. As bacteria that live in your mouth eat the foods you eat, they release acid as a waste product. This acid etches the surface of your tooth enamel where more bacteria will grow and etch more until there is a hole. A filling is the material used to replace the decayed portion of a tooth removed to stop more decay from developing. It is essential to have proper home care, such as brushing and flossing, to ensure a long happy life with your new filling.

Saliva in your mouth not only helps you digest food, it also helps repair teeth from the exposure of acid from bacteria or acidic foods, such as fruit juice, wine or vinegary foods. The minerals found in saliva actually attach to the enamel surface and, over time, will rebuild a tooth if the decay is confined to the enamel. Some medications alter the amount and quality of saliva wherein the tooth maintenance ability is halted. For these people, a whole new diet is required to keep teeth from decaying.

A chipped tooth edge on a front tooth can be repaired with a filling if the chip is not too big. The filling material can match the colour of the existing tooth really well so it is hardly noticeable when finished. Larger chips require more extensive work than a filling, such as a veneer or crown.

If a tooth is discoloured, then tooth coloured filling material can be bonded over the front side of the tooth to hide the discolouration. This procedure is actually a veneer process where tooth coloured filling material (composite) is used instead of porcelain.

As we age, our teeth become worn down. Fillings can be used to replace those worn down areas on the biting surface or at the gum line where exposed roots become ditched out. Not all areas can be successfully restored with fillings, but many can.

What types of fillings are there?

Dental fillings can be made from a variety of materials, including gold, silver alloy, composite, ceramic or other metals. Each filling material has its advantages and disadvantages, as well as vary in cost.

Gold fillings were the best and most widely used fillings on adults in the 1950s through to the 1970s. Tiny pieces of gold foil were hammered into the prepared space on a tooth to form a perfect seal between the tooth and filling. Gold is very compatible with the rest of the body and impervious to foods and saliva and would last a very long time. However, the hammering process turned out to damage the nerves of some teeth and not many people today like the look of gold in their mouth, so they are rarely used.

Silver fillings, or amalgam fillings, have been used for over a hundred years and, until recently, were the most common filling material in children and young adults. Silver alloy is a mixture of silver, mercury, tin and copper. The material comes in two parts, the mercury in one part and the other metals in powder form. When the two parts are vigorously mixed together, a pellet of silver alloy is formed that will begin to harden in about 5 minutes. Although there is much controversy over the use of silver alloy as dental fillings, they are still considered safe and cost effective by many countries, however unsightly they may be.

Composite fillings are tooth coloured fillings made from a mixture of resin and quartz crystals. Today, the resin in composite is light activated where a bright blue light is applied to the doughy material to harden it. After the tooth has been prepared, several layers of bonding agents are applied to the tooth surface to allow the composite filling material to chemically bond to the tooth. Composite fillings come in a variety of shades to match the many colours of teeth in the population.

Ceramic fillings are made of porcelain, zirconium or other ceramics which are made in a dental laboratory then bonded to the tooth at a subsequent appointment. Ceramic fillings are the “gold fillings” of today. They are very compatible with fluids in the mouth, are extremely strong and look great. Ceramic fillings can replace large missing portions of a tooth as they have inherent strength from the manufacturing process by the lab. However, they are the most costly and can cost as much or more than a crown.

How long do fillings last?

The life span of fillings depends on many factors, including the size of the filling and the material in which they are made and, of course, how well they are looked after. The failure of a filling can be caused by new decay around the filling, trauma or when a filling starts to leak. A leaking filling is when a space develops where the filling meets the tooth, also called the margin, due to decomposition of the filling or cement that hold them in place.

Gold and ceramic fillings can last a lifetime as long as they are kept free from clinging bacteria which would cause new decay. The materials used for these fillings do not break down over time which is why they can last so long. The weak link in a ceramic or gold filling is the margin, where the cement that hold them in place is exposed. If a dark line develops around a ceramic or gold filling, then it must be replaced.

Composite and amalgam fillings are made of a material that slowly breaks down over time. Therefore, they do have a lifespan. In composite fillings, the average life span is 5-10 years, which is influenced by the size of the filling placed. Small fillings can last up to 10 years and large fillings about 5 years. Amalgam fillings last between 12-20 years and their durability is also affected by their size.

Does it hurt To get a filling?

A filling, like most dental procedures, is not uncomfortable with anaesthesia. Your dentist will try to minimise any sensation during the procedure by administering a local anaesthetic to the area being treated. You will still be awake and able to interact with your dentist during the procedure.

Administering local anaesthetic these days is very easy. First, the dentist will apply a numbing gel to gums where the injection will occur. Then after a minute or so, the local anaesthetic will be injected into the site. You may feel a slight sensation as the first bit of anaesthetic is delivered to the site. It usually takes 3-5 minutes to effectively numb top teeth and a bit longer for lower teeth. The anaesthetic lasts from 1-6 hours depending on location and type of anaesthetic used.

Are silver fillings safe?

The answer to whether or not silver fillings (amalgam fillings) are safe is yes, no and maybe, depending on the research and evidence you believe. The amalgam safety controversy has existed ever since silver fillings were first introduced in the 1820s. Silver fillings contain mercury and the issue is not if mercury is toxic, but if the mercury escapes from amalgam fillings and causes harm.

The American Dental Association has determined that amalgam fillings are a safe and effective method of filling cavities.

The New Zealand Dental Association also believes that amalgam fillings are safe but should not be placed or removed on women during pregnancy.

However, there are several countries in Europe that have banned the use of amalgam fillings for health and environmental safety considerations. There are many other interest groups that state amalgam fillings cause many illnesses and ailments. The internet can provide much information on both views of amalgam safety.

Our position at Kowhai Dental is that if you think amalgam fillings are harmful, then they probably will be to you. It is your choice and the effects will most likely follow your belief.

Do fillings need to be replaced?

Fillings placed in the tooth that start out as a pliable material and then harden, such as amalgam fillings or composite fillings), will need to be replaced as the material eventually breaks down. When the material breaks down, a small gap develops between the tooth and filling which allows bacteria to grow and ultimately causes decay. Fillings that are manufactured in a lab and then placed in a tooth are made from materials that do not break down over time and do not need to be replaced nearly as often.

There are other reasons that require the replacement of fillings, such as decay in a new area of the tooth, a cracked or chipped tooth, or discolouration of a filling in a front tooth. Regular dental checkups allow your dentist to monitor the state of fillings and advise you when replacement is needed.