Umhlanga Dental
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• X-Rays
question Why are X-rays (radiographs) necessary?
answer Dental x-rays provide valuable information which your dentist could not detect otherwise. With the help of x-rays, your dentist can look at what is happening in areas that are not visible clinically. X-rays can detect cavities between the teeth, and can depict approximately how deep a cavity extends relative to the nerve. They can also help diagnose periodontal disease, abscesses, cysts, tumours, developmental abnormalities and infections in the bone.

question How often should x-rays be taken?
answer Typically every new patient should have a complete set of x-rays taken (about 18 films) to serve as a baseline. This set is taken every 3-5 years depending on the patient’s needs and history. A set of 4 “bitewing” films are taken once each year to check for cavities between the teeth and to monitor their progression. A panorex x-ray is a film that is taken while you stand still and the x-ray head rotates around you, providing one solid film of your jaws and teeth. A panorex is recommended for children in order to evaluate their need for orthodontics, for teenagers and young adults to evaluate the growth of the wisdom teeth and decide if they need to be removed, and for adults of all ages to evaluate for possible cysts and abnormal growths. A periapical film refers to a single film that is usually taken whenever the dentist would need to evaluate a specific area of concern.

x-ray question How much radiation is in a traditional dental X-ray, and should I be concerned?
answer Typically, the amount of radiation involved poses a much smaller risk than many undetected and untreated dental problems. Even so, all dentists should use a lead vest with a thyroid collar for extra protection. Each dental x-ray is about 0.5 mrem per film and a complete set is about 9 mrem. Just to put the amount of radiation into perspective, a barium enema: lower GI series is 875 mrem, and a mammogram is 500 mrem per breast. Note the average person is exposed to about 360 mrem just from their environment (i.e. their foods sources and outer space). In other words, you can have about 10,000 dental x-rays before you reach the maximum allowable amount per year.
Note: digital x-rays have even less radiation than traditional x-rays.

question How are digital X-rays different from traditional x-rays?
answer Digital x-rays play an invaluable role in the diagnosis of dental problems. Digital x-rays eliminate many radiation worries because they require 90% less radiation than conventional film x-rays. So a complete set of x-rays (18 films) has the radiation of only 2 conventional films. It is as accurate as conventional x-rays and even reveals things traditional films cannot. You can correct contrast, and colour-adjust to reveal hidden problems. We can measure things more accurately and back-light teeth to see things that never could be seen with conventional film. Digital x-rays are instantaneous. Once the sensor is exposed to digital x-rays, the image is sent directly to the computer monitor for immediate viewing. So please allow your dentist to take the necessary digital x-rays to get the whole picture and make an accurate diagnosis.

question Why do dentists need to take a new full set of x-rays every 3-5 years?
answer Routine x-rays help to prevent a small cavity from becoming a larger problem. Even if a patient is seen every six months, cavities can remain undetected between the teeth unless x-rays are taken periodically. Additionally, a comprehensive set of x-rays will show if an old root canal filling is failing, if there is periodontal disease (bone loss), and if there is any decay recurring beneath the margins of older restorations, etc. Anyone who has old restorations in the mouth or is under dental care should have a full set every three years. A younger person with good home care and very few restorations and dental problems can have a full set every 5 years. It is still recommended however; that people have routine bitewing x-rays every year to check for the cavities that can develop in-between the back teeth due to a lack of flossing.

There are many patients who refuse to take x-rays when advised to do so. They later wonder why all of a sudden, their tooth which recently started causing them discomfort, now needs a root canal or an extraction because the cavity has grown beyond the size of just a simple filling. If they allowed the dentist to take those periodic x-rays, then that lesion would have been caught when it was small, easy to fix, and less expensive to restore. Insurance companies usually allow a full set of x-rays to be taken every 3 years because they know it is less expensive to reimburse for preventative care than to reimburse for crowns and root canals later.