It is common knowledge that a person’s smile can be an asset or a detriment to one’s self image, personal happiness and financial success. The centerpiece of that smile are the teeth. Studies have reported that the first body part that the outside world sees are your teeth and lips, then your eyes, and then your physique.
How many times has a person’s teeth affected your view of them? Is it more difficult for you to trust or relate to someone with missing, crooked or darkened teeth. Would you feel comfortable buying a car from them or allowing them to handle your money or having them operate on your body or even serve you a meal.
In the 21st century, orthodontics, implants, crowns and bridges, partial and full dentures allows dentistry to straighten crooked and replace missing teeth. But these treatments come with a high price, both monetarily and, especially for the fearful or phobic patient, with great anxiety.
Even though the natural shade for teeth is slightly yellow, we live in a world where white teeth are advertised as being the norm. Television and movie actors do all kinds of cosmetic surgery, and it most often includes whitening (bleaching) their teeth. The public, who are so enamored with these personalities, has followed suit. Therefore, it is not surprising that the industry that manufactures tooth whiteners (bleaching agents) has grown to exponentially within the last 20 years.
There are many ways to lighten or whiten the shade of the teeth, including composite fillings, porcelain facings (particularly Luminers) or even crowns. These procedures, especially for those that have teeth without decay or fillings, or have teeth that are in alignment, or haven’t had any previous dental treatment, are unnecessary. These treatments may also require some tooth preparation and or a local anesthestic (Novocaine), or other means of reducing anxiety or discomfort before, during and after the procedures.
The major reason patients have their teeth bleached is esthetics (appearance). It is a very conservative, cost-effective way to immediately impact one’s smile. No tooth preparation or local anesthetic is necessary. The procedure can be done on from one to six upper and/or lower anterior (front) teeth.
There are many types of stains or discolorations that cannot be removed with a normal dental prophylaxis ( professional cleaning). Some stains are more superficial and are only found in the enamel (outer layer). Others may involve the deeper layer of tooth called the dentin.
There are many causes of tooth staining.
1. The use of the antibiotic tetracycline during the formation of the teeth can cause tetracyline staining.
2. One sign of the genetic syndrome dentinogenesis imperfecta is also deep staining.
3. Fluoride can cause mottling and staining of the teeth (fluorosis).
4. Teeth usually and naturally darken with age.
5. A tooth that is non-vital (dead) can darken over time.
Bleaching is a tooth whitening procedure that can be divided into two main categories:
1.Vital bleaching (which is done on live teeth)
2. Non-vital bleaching (which is done on teeth that are not alive).
Further classification is based on where the treatments take place and who is responsible for carrying out the procedure:
1. In the dental office by dental personnel (In-Office)
2. At home by the patient (At-Home)
3. The preferred combination of 1+2.
The technique of in-office tooth bleaching uses two different viscous gel forms of peroxide. They are 30-35% carbamide or hydrogen peroxide. There is debate over which material is safer and performs better, especially among the companies that produce the whiteners. Clinically, they are both acceptable products as long as the proper precautions are taken.
The three main side effects of bleaching are:
1. Damage to tooth structure and pulp (nerve).
2. Damage to the periodontal (gums) tissue.
3. Increased tooth sensitivity.
It should be noted that these products will not bleach fillings or crowns or facings. In order to match the new shade of the teeth, these may need to be replaced, resulting in otherwise unnecessary treatment.
The procedure is as follows:
The gel is placed in a custom–made mouthguard. This mouth tray delivers the material and allows it to remain on the teeth for a pre-determined length of time. Great care should be taken to protect the gingiva from damage using barrier or blocking materials and rubber dams.
The use of heat or high powered light sources such as PAC lights, dental curing lights and dental lasers speed up the process, but may cause more sensitivity as a result.
The rapid increase in the creation and production of home bleaching products using hydrogen and carbamide peroxide gels in lower concentrations and custom made trays has made bleaching more accessible to, and less costly for, the general public.
Patients must be more willing to work with the dentist in the office and participate in the process at home. They are required to wear the mouthguard filled with material for up to two hours at a time and for as many sessions as it takes to achieve the desired results. The weaker concentration of the active ingredients may lengthen the time required and may also lessen the potential for harm.
There is always a deluge of new products with other whitening formulas which claim less sensitivity. There is even a new toothbrush on the market which claims to use laser technology to speed up the bleaching process.
The bleaching material combines with water to produce free oxygen radicals which penetrate into the enamel and dentin to oxidize discolorations and makes the stain more solluble. The stains are dissolved into the saliva or an oral rinse.
In-Office whiteners can whiten the teeth more quickly due to higher concentrations of active ingredients. On the other hand, higher concentrations are more likely to irritate the gingiva. Supervision of the ideal combination of office/home bleaching allows more aggressive and safer treatment and offers more possibilities of success.
The need for one to three or more visits would be determined by the concentration and type of the whitener, the viscosity of the gel, the tray design and the results that you want. If the patient is actively involved in the process, then it will take the least time to complete. The number of teeth and visits and the amount of chair time and materials used determines the fee for tooth bleaching.
Today, there are also several toothpastes on the market that contain whitening agents. However, the small amount of time patients brush and the low concentration of active ingredients result in a more unpredictable period to attain the desired results. Whitening toothpastes are the least costly, least harmful and least effective method. They can be used as an adjunct to the other methods and can also help to maintain the desired color change.
The latest addition to at home bleaching products are 3″x2″ sticky strips impregnated with a lower (7-14%) carbamide impreganated is adapted and easily adheres to the front teeth. The strips are worn on the teeth twice daily, for 1/2 hour, for up to two weeks. Advertisements claim that the whitening can last for at least 6 months. Therefore, like most, the procedure will have to be repeated periodically. It is a fact that those methods using higher percentages of bleaching chemicals will last longer. But the the ease of handling and the relatively low cost makes it a product that has impacted on the home bleaching market and further reduced the dentist ‘s role. One would assume,that the lower % of bleaching agent would result in a decreased chance of sensitivity.
A darkened non-vital tooth that has had Endodontics (root canal therapy) can be whitened by a combination of internal bleaching with a 30% hydrogen peroxide or sodium perborate solution and external bleaching with carbamide or hydrogen peroxide.
In addition to the two previously mentioned forms of peroxide, all whitening agents also may contain other active ingredients, colorings, flavoring and thickening agents. From a health standpoint the use of these potentially harmful materials is of concern. Yet, for varied and sometimes very personal reasons, many people choose to whiten their teeth, and therefore an educated compromise must be made.