January 24, 2022
Tooth enamel may be the hardest part of the tooth but it can get eroded due to different factors. Where demineralization damages it, the process of re-mineralization helps to strengthen it and prevent caries. Though remineralization is a natural process that takes place in favorable conditions, sometimes it needs to be boosted. Several methods already exist such as the use of fluoridated toothpaste or even fluoridated water to promote re-mineralization but these methods are for all dental caries. Phocal discs with fluoride are a method for preventing or managing caries between the teeth.
What are phocal discs with fluoride?
Even if you brush your teeth diligently, the area between the teeth is still left untouched. Flossing and the use of interproximal brushes are recommended by dentists to keep these hard to reach areas plaque-free. Still caries do develop in these areas and need focused treatment. Dentists begin with a visual inspection on complaints of pain by the patient. However, interproximal caries are hard to locate in a visual inspection, but bitewing x-rays are taken to pinpoint areas of concern.
Phocal discs with flouride are used for incipient cavities that are yet to reach the dentin. You can call them surface caries. These discs are unique in themselves as they are placed directly at the needed site. They are specifically meant for cavities between adjacent teeth. Available in disc shapes, these are of two types:
1. Apf disks - pink acidulated phosphate fluoride
2. pHn disks - yellow non-acidic sodium fluoride
Both the types contain the same amount of fluoride, i.e. 0.1135mg of sodium fluoride. But the difference lies in the level of acidity. The Apf discs are somewhat more acidic and designed to clean as well as etch the tooth surface. This helps in greater penetration of fluoride to promote re-mineralization. On the other hand, the pHn discs are used in cases where the patient has ceramic crowns or tooth colored fillings as etching is not desirable in such situations.
Uses
Prevention of caries or their early management contributes to long term dental health. It also helps to reduce the need for expensive and more invasive procedures at a later stage. These discs are:
• Used for delivery of fluoride at interproximal areas to promote re-mineralization
• To prevent caries in the areas between adjoining teeth. This is the area that is unreachable with normal tooth brush.
• As it can be placed directly at the affected site, it ensures delivery of fluoride exactly where it is needed.
• Other than interproximal areas, these are also used at furcation sites.
• Tooth restoration margins can also be fluoridated with the help of these discs.
Method of Application
As these are small discs that need to be placed directly at the site of the caries, it can only be done by the dentist. First and foremost the site is cleaned and dried. If the site of placement is moist then the disc is likely to soften, making placement difficult. The disc can be trimmed or folded to fit in tight areas.
In the case where there is enough space the disc is inserted using forceps or by the hand directly. Space between the back teeth is restricted and the dentist may need to separate with wedges before placing the disc. A curing light is used for 3 to 10 seconds to speed up the process. In situations where the dentist feels extending fluoride time will be more beneficial, he may partially cover the disc with varnish.
Mode of Action
Once placed these fluoride discs begin to expand and become gel like in constitution. They release fluoride at the site of placement for about 10 minutes and eventually disintegrate totally.
Precautions
The use of fluoride has health implications that cannot be ignored. One should never swallow these discs. Further, if the patient uses any other fluoridation method such as fluoride gels or rinses, it should be avoided on the day of placement. Patients are asked not to eat or drink anything for about 30 minutes after placement to ensure that full re-mineralization is able to take place.