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singapore he alth
MAY⁄ JUN 2012
News
Close to the real thing Getting the perfect smile without dentures has made dental implants an increasingly popular choice
If you have lost a tooth, a dental implant is as close to the real thing as you will get. There is a growing demand for them in Singapore from a spectrum of people – teens, young professionals, the middle-aged and the elderly. The National Dental Centre of Singapore (NDC) has seen a steady increase in the number of implant patients, with the number of implants placed tripling between 2005 and 2010. Improvements in technology and techniques plus rising awareness have fuelled demand, said Dr See Toh Yoong Liang, Senior Registrar, Prosthodontic Unit, Department of Restorative Dentistry. He said: “In the last decade, demand grew as science improved. We can now predict with greater accuracy the success rate of implants. Lower jaw implants, for example, have a success rate of 95 per cent while it’s 90 per cent for the upper jaw.” An option for missing teeth Dr See Toh explained that a dental implant, as an option for replacing a missing tooth, has several advantages compared to other alternatives. Implants do not affect other teeth, unlike dental bridges, where the adjacent teeth have to be filed down. Compared to dentures, implants are more comfortable, less obtrusive in the mouth and do not trap food. Elderly people who have lost most of their teeth may opt for implants that function as clips for securing overdentures. For this, two implants are placed in the jaw. But instead of adding prosthetic teeth onto them, dentures with corresponding inserts on their undersides are fitted onto the implants.
“This is a relatively cheap option, easy to maintain and not as complicated compared to a regular implant,” said Dr See Toh. But dental implants do have associated risks and are not for everyone. For instance, patients with low bone density in the jaw or medical problems that limit wound healing may not be suitable for such implants. Proper investigation before surgery Dr See Toh said, due to these risks, it is important that dentists conduct examinations and use diagnostic procedures, such as x-rays and conebeam scans, to assess the width and density of the jaw bone before surgery can take place. Such images allow them to check if there is enough bone to support an implant and determine the length of the implant. Only then can the operation take place. “The standard process, without any complications, takes about three to four months,” said Dr See Toh. “In complicated cases, where there is insufficient bone and bone grafting is required, the process can take six to eight months.” Bone grafting is a procedure to “grow” more bone. This may seem like a long time, but the process is important to help the dentist identify structures to avoid, such as nerves and bones, and use an implant of the right size. A proper healing period also allows the bone to heal and fuse well with the implant – a process known as osseointegration. “You don’t want to load the implant (with a permanent crown) too soon. We usually allow at least two months before attaching a crown,” said Dr See Toh. “There have been cases where immediate loading of a crown onto the implant root resulted in higher risks of failure. This is because the crown puts pressure on the
implant before it is stable. However, a temporary crown or prosthesis may be fitted in a way that does not add pressure on the new implant.”
The cover screw is removed in readiness for the next stage.
The photo above shows models of parts of a dental implant
Are mini implants safe? New to the market are mini implants, which use much smaller screws – and several of them – to secure a crown to the jawbone. They are being marketed as a cheaper and faster alternative to regular implants, but people should exercise caution if they are considering them for longterm use.
The abutment is attached to the implant.
A The screw is first fixed to the jawbone. It can be made of titanium, titanium alloy, ceramic or zirconia.
B The abutment fits on top of the implant.
C The crown goes on the tip of the abutment. It can be made of zirconia, gold alloy or ceramic. The typical cost of a dental implant procedure starts from $3,500.
Dr See Toh carries out a dental implant for a patient.
Steps in dental implant surgery A hole is drilled for the implant. A cover screw is put in and left till the bone fuses and is ready for the implant.
About dental implants
PHOTOS: ALECIA NEO
BY Sheralyn Tay
The final stage where the crown (prosthetic tooth) is attached.
“Typically, mini implants are used at NDC as anchorage in orthodontic treatments,” said Dr See Toh. “There is not a lot of evidence to support using mini implants as a permanent tooth replacement solution. This is because they have a very narrow diameter and, therefore, a higher risk of breakage or fracture over the long term.” NDC has treated a number of problems resulting from the improper use of mini implants, said Dr See Toh. “We generally see more complications arising from mini implants used as a permanent measure, compared with conventional implants with wider diameters.” Knowing the options, undergoing comprehensive checks and choosing the right type of dental implant will help to improve the success rate of replacing a missing tooth. “Implants are subject to considerable wear and tear from chewing and biting, so it is very important to choose the right type,” added Dr See Toh. After surgery, people should care for their implants by brushing and flossing, and going for a regular dental exam once a year. People who smoke should quit and those with diabetes should control their sugar levels, as both can affect bone healing and the success of implants.