The laser is one of the ultimate high-tech inventions which symbolize our modern technological society. LASER is an acronym which stands for “light amplification by the stimulation emission of radiation” and delivers energy in the form of light.
Lasers were used in dentistry as long ago as the 1990’s but are still not part of every dentist’s day-to- day equipment because of the very high cost of the hardware and certain limitations of use.
A dental laser emits a high energy beam of strong coherent light which can be of varying strength. The special light emitted from a laser has greater powers of penetration than ordinary non-coherent light, and a so-called “soft” or low-level beam heats up tissues and can help with wound healing by encouraging better blood flow, for example, whilst a “hard” laser can actually reduce or remove tissue.
The uses and benefits of a dental laser
Lasers are used in the field of dentistry sometimes for:
- gum treatments,
- enhanced wound healing,
- treatment of facial pain,
- sterilizing root canals of teeth,
- eliminating bacteria in carious cavities, and
- preparing the hard tissues in teeth to receive a suitable filling.
There is no vibration as there is with a normal dental drill. At high levels the energy, delivered as light, can actually cut through tooth substance, whilst at lower levels the energy produces heat which can be useful for “curing”, i.e. hardening certain types of white, or tooth-coloured, fillings.
A suitable dental laser can be used like a scalpel to reshape or remove gum tissue, and the concentrated heat produced can effectively kill bacteria in pockets of diseased gum tissue. This technology can also be useful for biopsy where a small amount of tissue is removed for examination under a microscope to identify early cancer.
The higher energy forms of lasers can be used to eradicate bacteria in dental decay lesions of teeth and even to remove hard tooth tissue avoiding the need to drill in some cases.
Because the energy of a laser is pulsed, or in effect switches on and off extremely rapidly, it does not seem to trigger nerve endings so easily and so can sometimes, but not always, avoid the need for a local anaesthetic, i.e. an injection, which is great news for many!
Laser treatment may also be very useful to treat sensitive areas of teeth which have been caused by abrasion from injudicious use of the toothbrush or from acid erosion caused by certain types of drinks. The exposed dentine layer of a tooth, once the covering enamel layer has gone, has minute tubules which communicate with the pulp in the centre where the nerves are, so quite often exposed dentine is sensitive to stimuli from sweet, cold, or acid food or drinks. The beam pulses can quickly and effectively seal these tubules and is generally much more effective than any sensitive formula toothpaste.
Low-level laser energy is also used in bleaching procedures in order to enhance and speed up the whitening process, which it does by activating the bleaching gel to more easily release oxygen molecules which cause the actual whitening of tooth substance. If you bleach your teeth at home using a proprietary gel it can take up to two weeks of daily applications, whereas in the dental office a superior result of up to six shades lighter can usually be achieved within an hour! However this type is usually not as long lasting as with the home application, so often the latter is also required.
Drawbacks of lasers
Lasers have their limitations however when it comes to replacing the traditional drill, since they won’t effectively remove old fillings, and they can’t properly be used where access is not straightforward such is in the sides of teeth or in between them. They can’t be used on silver amalgam fillings, because the heat could vaporize mercury which could be potentially hazardous to health. So such fillings have to be removed using a conventional high-speed drill.
Lasers are thus a very useful adjunct to dental treatments but unfortunately cannot as yet totally replace the traditional drill. It is often necessary for instance for the dentist to drill away old filling material or certain less accessible parts of a tooth to get to decay, before the laser can be used to destroy bacteria or perfect the final preparation.
Another obvious drawback is in regards to the high costs of lasers in dentistry. These machines have needed years of research and development, which along with hardware costs of manufacture, result in expensive equipment for the end user. If and when lasers become more widespread, these costs should come down. Another cost involved is from the extra investment the dentist must put into training for laser use.
The American Dental Association has not as yet given its final seal of Acceptance for dental lasers, since they cannot totally replace traditional treatment procedures but they accept their use as safe in expert hands. They call for a greater evidence-base in the field.
Lasers are proven as superior for soft tissue surgery with less bleeding and quicker recovery times, and also show promise in the treatment of dental decay, root canal therapy, and cosmetic procedures.
So it’s not surprising that they are becoming increasingly popular for use in dentistry, making for quicker and more comfortable treatment procedures where appropriate.