Dentist London - Dental materials in General Dentistry

Do you have questions about restoration materials you need to ask your dentist? London practitioner Hans Lock explains everything you need to know.This information is provided to help you make decisions about the selection of materials as tooth restorations in your mouth. Many types of metals are used in dentistry for the replacement and rehabilitation of oral structures. Most of these metals are considered to be inert when placed in the body, while others have been criticised as potential toxins or allergens. Plastics and ceramics are used commonly as tooth restoratives, and these have not been shown to have adverse biologic or significant allergic responses.The following information will help you to make decisions about the type of tooth restorations you prefer to be placed in your mouth.

Restoration of missing parts of singleteeth (fillings)

Silver amalgam has been used for about 160 years for tooth restorations. This alloy contains silver, tin, copper, zinc, and about 50% mercury. It has been a highly successful and amalgam use is still supported by the British Dental Association and other health groups and dental associations worldwide. A few people in the overall population may be allergic to the elements in the silver amalgam. Statistically, amalgam tends to expand over time, thereby coursing a pressure inside the tooth. Eventually the risk of fracturing the tooth will increase as a result, occasionally to the extent where it is not possible to save the fractured tooth. However, you have several other options for tooth-restorations (fillings).

Your Choices for Restoration of MissingParts of Single Teeth (filling):

• Silver amalgam. Average longevity about 15 years, silver coloured, low-moderate initial cost. Best used in small to medium sized restorations (up to a maximum of 2 thirds of the entire tooth surface) of posterior teeth (premolars and molars).
• Gold inlays and onlays Average longevity 20 years to life, gold coloured, moderate to high initial cost. May be used in most locations of any size where metal is not displayed to an objectionable level. Very strong material. Very long lifespan.
• Resin (plastic)-direct (one-day appointment placement). Average longevity 10-15 years, tooth coloured, moderate cost. Best used in small to medium sized restorations (up to a maximum of 2 thirds of the entire surface of the tooth) for any teeth. Considered at this time to be at least comparable to silver amalgam's service potential - both in regards to the risk of fracture of the filling itself but particularly in regards to the prevention of the tooth involved.
• Resin (plastic)-indirect (two-appointment placement). Average longevity (expected) 10-15 years, tooth coloured, moderate to high initial cost. Best used in medium to large restorations for posterior teeth (premolars and molars).
• Ceramic-indirect (two-appointment placement. Average longevity 10-15 years, tooth coloured, moderate to high initial cost, Best used in moderate to large restorations for any teeth.
• Resin (plastic)-indirect (two-appointment placement). Average longevity (expected) 10-15 years, tooth coloured, moderate to high initial cost. Best used in medium to large restorations for posterior teeth (premolars and molars).
• Ceramic-indirect (two-appointment placement Average longevity 10-15 years, tooth coloured, moderate to high initial cost, Best used in moderate to large restorations for any teeth.

Crowns or Fixed Prostheses/Bridges.

Gold alloys have been used for many years for the construction of crowns or fixed prostheses. Gold alloys provide excellent, strong, long lasting service. Other alloys are used as well. Three major types of alloys are now available:

• High-noble metal. Mostly gold, but also palladium, silver, and occasionally platinum, zinc, and copper.
• Noble metal. Mostly palladium, but also silver, gold, an other trace metals.
• Base metal. Mostly nickel, but also chrome or cobalt and other base materials.

All of the above alloys are used either as the sole constituent of a crown or as a thimble on which porcelain is fired (baked). Most people have no biologic response to any of these categories of metals, but some people, especially females, have adverse tissue responses to base metals. If you know of allergies you have to metals, please tell us. We usually use noble or high-noble metals. The cost of these is somewhat higher than base metal.Crowns are the choice of option in situations where the remaining part of the tooth is weakened considerably to the extent where an additional decay or fracture of the toothmeans a risk of loosing it. Bridges are used in situations where a tooth is already lost and needs to be replaced for some reason. It is the first choice of option if the neighbouring teeth to the lost tooth/teeth are also weakened. Alternative dental implants may be an alternative (see information regarding dental implants).

Porcelain crowns

Porcelain crowns are used where only a small amount of tooth is left. During the local anesthetic the tooth is carefully cut into the right form and an impression of the tooth is made. The impression is send to a dental laboratory, where the technician produces a porcelain restoration with the right colour and shape according to our instructions. A new appointment with the dentist is made, you are anaesthetized, the temporary filling is taken of, the tooth is disinfected and the crown is bonded to the tooth.

Your Choices for Crowns (Caps) or Fixed Prostheses (Bridges)

Fixed prostheses are strongest when metal is used with or without porcelain on it; but, in certain limited situations, allceramic or polymer fixed prostheses may be used as described below.

• Metal alone. High-noble, noble, or base metal. Average longevity 20 years to life, gold or "silver" colour, moderate to high initial cost. May be used in any area where metal display is not objectionable since they are not tooth-coloured.
• Porcelain fused-to-metal. Average longevity 10-20 years, tooth coloured, moderate to high initial cost. May be used in any area where extreme biting stress is not present, and patient does not have severe tooth grinding habit.
• Ceramic non-metal. These restorations are constructed from ceramic alone. Average longevity is 10-plus years, moderate to high initial cost. May be used when extreme stress or grinding habits are not present. All ceramic fixed prostheses may be used a few clinical situations, but they are improving constantly. They are first choice of option in high aesthetic situations - i.e. the front teeth. Your Choices for

Crowns (Caps) or Fixed Prostheses (Bridges):

Porcelain veneers (also known as laminates) are used to recreate broken or worn teeth, or to change a tooth's appearance. They are extremely thin, however very strong when bonded to the tooth. You can compare veneers with a new enamel in the desirable colour and shape on the front surfaces of the teeth.Polymer (plastic). These restorations may be single crowns or bridges. Average longevity is currently unknown, since they are relatively new, but success has been reported up to 5 years.The Mermaid Dental Clinic is a high quality dentist; London-based the clinic offers a full range of dental services with great patient care, using the latest technology for painless and superior results. Situated in the West End, the staff are trained and equipped to treat every aspect of your dental needs with professionalism and expertise. You can make an appointment by calling 0207 580 1001.

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