تبييض الأسنان
جميع البشر يودون ويحبون أن تكون أسنانهم بيضاء متلألئة .. ليبتسموا براحة واطمئنان إلى أنه لن يسخر أو يستهزىء بهم أحد إذا ما ظهرت أسنانهم للناس ..
ولهذا يحرصون بشدة وقوة على تبييض أسنانهم كلما شعروا أن لونها أصبح قاتما أو غامقا مختلفا عن الأسنان الطبيعية ..
ما هي عملية تبييض الأسنان ؟
بكلمات بسيطة وسهلة ومفهومة لكل البشر ..هي عملية كيميائية يتم فيها وضع مادة بشكل هلامي مركبة بشكل أساسي من جزيىء الماء الأوكسجيني بتركيز عالٍ قد يصل في بعض المنتجات إلى 40% .. توضع هذه المادة على السطوح الخارجية المقابلة للشفتين للأسنان الأمامية العشرة العلوية والسفلية بعد تطبيق مادة واقية للثة ..ثم يُسلط ضوء أزرق ذي موجات قصيرة لينشط المادة الهلامية ويفكهها ويسهل دخولها إلى طبقة العاج عبر طبقة الميناء المغطية لسطوح الأسنان وبذلك يتم تفاعل كيميائي يحول اللون الأصفر أو القاتم للعاج إلى لون فاتح يشف من خلال الميناء فتظهر الأسنان بلون أبيض ناصع ..
استطبابات تبييض الأسنان
1- الأسنان الفلورية التي تغطيها بقع رمادية أو سوداء نتيجة شرب الشخص لمياه مشبعة بمادة الفلور أثناء الطفولة أو الحمل.
2- الأسنان البرتقالية وهي تحدث نتيجة تناول مادة دوائية تسمى التتراسكلين أثناء الحمل أو الطفولة .
3- طبيعة خاصة تحصل عند بعض البشر فتكون أسنانهم ذات ألوان غامقة بنية أو رمادية .
4- تقدم العمر حيث تميل الأسنان إلى الإصفرار أكثر كلما تقدم الإنسان في العمر .
حالة سريرية
جاءتنا إلى العيادة الأسبوع الماضي شابة متوسطة العمر تشكو من اصفرار أسنانها واستيائها الشديد من لونها القاتم 
طالبة إجراء عملية التبييض.
قمنا في البداية بعملية تنظيف الأسنان من الرواسب الجيرية المتراكمة على أسنانها ثم تلميعها بمعجون خاص لهذا الغرض .. وبعدها وضعنا مادة واقية للثة لحمايتها من التأثر بمادة التبييض الحارقة إذا لامست اللثة أو الجلد ..ثم وضعنا المادة الهلامية التي تكون بشكل جل على السطوح الخارجية للأسنان الأمامية العلوية والسفلية وسلطنا عليها الضور الخاص بذلك لمدة تقارب النصف ساعة على ثلاث فترات وبعدها حصلنا على هذه النتيجة الرائعة 
التي جعلت المريضة في غاية الفرح والسرور والحبور .
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Tooth bleaching
From Wikipedia, the free encyclopedia
| Tooth bleaching | |
|---|---|
| Intervention | |
 Teeth Whitening Kits for Home Use | |
| MeSH | D014073 |
Dental bleaching, also known as tooth whitening, is a common procedure in general dentistry but most especially in the field ofcosmetic dentistry. According to the FDA, whitening restores natural tooth color and bleaching whitens beyond the natural color. There are many methods available, such as brushing, bleaching strips, bleaching pen, bleaching gel, laser bleaching, and natural bleaching.
Bleaching methods use carbamide peroxide which reacts with water to form hydrogen peroxide. Carbamide peroxide has about a third of the strength of hydrogen peroxide. This means that a 15% solution of carbamide peroxide is the rough equivalent of a 5% solution of hydrogen peroxide. The peroxide oxidizing agent penetrates the porosities in the rod-like crystal structure of enamel and bleaches stain deposits in the dentin. Power bleaching uses light energy to accelerate the process of bleaching in a dental office.
Tooth bleaching is not a modern invention. Ancient Romans, for example, utilized urine and goat milk as a product to make and keep their teeth whiter.[1]
Contents[hide] |
[edit]Causes of tooth discoloration
![[icon]](http://en.wikipedia.org/wiki/File:Wiki_letter_w_cropped.svg){kind=small} | This section requires expansion.(September 2012) |
A child's deciduous teeth are generally whiter than the adult teeth that follow. As a person ages the adult teeth often become darker due to changes in the mineral structure of the tooth, as the enamel becomes less porous[citation needed] and phosphate-deficient. Teeth can also become stained by bacterial pigments, food-goods and vegetables rich withcarotenoids or xanthonoids. Certain antibacterial medications (like tetracycline) can also cause teeth stains or a reduction in the brilliance of the enamel.[2] Ingesting colored liquids like coffee, tea and red wine can also discolor teeth.
Other causes:
- Tetracyclines
- Enamel hypoplasia
- Fluorosis
- Age of the tooth: the teeth become more yellow or opaque and generally have a darker hue, usually after 50.
- Tea
- Coffee
- Tobacco ( tar and nicotine )
- Mate
- Wine and cola drinks consumed in excess
- Other foods and oral tobacco products with strong content of pigments
- Chlorhexidine (chemical bactericidal and bacteriostatic used as antiseptic in mouthwashes and toothpastes for the treatment of gingivitis and halitosis )
[edit]Methods
According to the American Dental Association, different whitening include: in-office bleaching, which is applied by a professional dentist; at-home bleaching, which is used at home by the patient; over-the-counter, which is applied by patients; and options called non-dental, which are offered at mall kiosks, spas, salons etc. There is also the option of whitening one's own teeth by natural teeth bleaching methods.
The ADA recommends to have one's teeth checked by a dentist before undergoing any whitening method. The dentist should examine the patient thoroughly: take a health and dental history (including allergies and sensitivities), observe hard and soft tissues, placement and conditions of restorations, and sometimes x-rays to determine the nature and depth of possible irregularities.
The whitening shade guides are used to measure tooth color. These shades determine the effectiveness of the whitening procedure, which may vary from two to seven shades.[3] The effects of bleaching can last for several months, but may vary depending on the lifestyle of the patient. Dentures can also be whitened using denture cleaners.
White-spot decalcifications may also be highlighted and become more noticeable directly following a whiting process, but with further applications the other parts of the teeth usually become more white and the spots less noticeable. Bleaching is not recommended if teeth have decay or infected gums. It is also least effective when the original tooth color is grayish and may require custom bleaching trays. Bleaching is most effective with yellow discolored teeth. However, whitener does not work where bonding has been used and neither is it effective on tooth-color filling. Other options to deal with such cases are the porcelain veneers or dental bonding.[4]
Internal staining of dentin can discolor the teeth from inside out. Internal bleaching can remedy this. If heavy staining or tetracycline damage is present on a patient's teeth, and whitening is ineffective (tetracycline staining may require prolonged bleaching, as it takes longer for the bleach to reach the dentin layer), there are other methods of whitening teeth. Bonding, which also masks tooth stains, is when a thin coating of composite material is applied to the front of a person's teeth and then cured with a blue light. A veneer can also mask tooth discoloration.
[edit]In-office
In-office bleaching procedures generally use a light-cured protective layer that is carefully painted on the gums and papilla (the tips of the gums between the teeth) to reduce the risk of chemical burns to the soft tissues. The bleaching agent is either carbamide peroxide, which breaks down in the mouth to form hydrogen peroxide, or hydrogen peroxide itself. The bleaching gel typically contains between 10% and 44% carbamide peroxide, which is roughly equivalent to a 3% to 16% hydrogen peroxide concentration.
[edit]Light-accelerated bleaching
Power or light-accelerated bleaching, sometimes colloquially referred to as laser bleaching (a common misconception since lasers are an older technology that was used before current technologies were developed), uses light energy to accelerate the process of bleaching in a dental office. Different types of energy can be used in this procedure, with the most common being halogen, LED, or plasma arc. Clinical trials have demonstrated that among these three options, halogen light is the best source for producing optimal treatment results.[5] The ideal source of energy should be high energy to excite the peroxide molecules without overheating the pulp of the tooth.[6] Lights are typically within the blue light spectrum as this has been found to contain the most effective wavelengths for initiating the hydrogen peroxide reaction. A power bleaching treatment typically involves isolation of soft tissue with a resin-based, light-curable barrier, application of a professional dental-grade hydrogen peroxide whitening gel (25-38% hydrogen peroxide), and exposure to the light source for 6–15 minutes. Recent technical advances have minimized heat and ultraviolet emissions, allowing for a shorter patient preparation procedure. Most power teeth whitening treatments can be done in approximately 30 minutes to one hour, in a single visit to a dental physician.
[edit]Internal bleaching
Internal bleaching procedures are performed on devitalized teeth that have undergone endodontic therapy (a.k.a. "Root Canal") but are discolored due to internal staining of the tooth structure by blood and other fluids that leaked in. Unlike external bleaching, which brightens teeth from the outside in, internal bleaching brightens teeth from the inside out. Bleaching the tooth internally involves drilling a hole to the pulp chamber, cleaning, sealing, and filling the root canal with a rubber-like substance, and placing a peroxide gel into the pulp chamber so the gel can work directly inside the tooth on the dentin layer.[citation needed] In this variation of whitening the peroxide is sealed within the tooth over a period of some days and replaced as needed, the so-called "walking bleach" technique.[citation needed]
[edit]At-home
Commercial whitening products intended for home use include gels, chewing gums, rinses, toothpastes, among others.[7] The ADA has published a list of accepted over-the-counter whitening products to help people choose appropriate whitening products.[8]
High-concentration home bleaching uses carbamide peroxide. Whitening is performed by applying a high concentration of oxidizing agentto the teeth with thin plastic trays for a short period of time, which produces quick results. The application trays ideally should be well-fitted to retain the bleaching gel, ensuring even and full tooth exposure to the gel. Trays will typically stay on the teeth for about 15–20 minutes. Trays are then removed and the procedure is repeated up to two more times.
Low-concentration whitening is far less effective. Low-concentration whitening involves purchasing a thin mouthguard or strip that holds a relatively low concentration of oxidizing agent next to the teeth for as long as several hours a day for a period of 5 to 14 days. Results can vary, depending on which application is chosen, with some people achieving whiter teeth in a few days, and others seeing very little results or no results at all. Dentists as well as some dental laboratories can make custom fitted whitening trays that will greatly improve the results achieved with an over-the-counter whitening method.
[edit]Natural methods
There are many popular natural ways to whiten one's teeth. Some natural teeth whitening methods can be very gentle on the teeth, while others can lead to enamel damage. One efficient type of natural teeth bleaching is through the use of malic acid,[9][10] a natural occurring acid in fruits that contribute to their pleasantly sour taste and is made by all living organisms. One simple way of natural tooth bleaching is by applying the pulp of crushed strawberries (which contains malic acid) to the teeth and leaving it there for five minutes. Remains of strawberry pulp can be removed by flossing the teeth. Another way is by 'gently and circularly' brushing one's teeth with some baking soda (an 'abrasive' teeth whitener) using a soft toothbrush. Malic acid and sodium bicarbonate are effective whitening treatments but should be used sparingly as both methods are not too gentle on the teeth. They could lead to enamel damage if used indiscriminately (i.e., more than a couple of times a week or so).
Apples, celery and carrots also support and help whitening teeth,[11] as they act like natural stain removers by increasing saliva production (the mouth's self-cleaning agent) and scrub the teeth clean. They help maintain a fresh breath by killing bacteria that produces halitosis. The juice of apples, especially green apples, contains malic acid (malic is derived from the Latin word for apple mālum; the acid was named after it).
Lemons are sometimes used as a whitening agent by squeezing the juice on the teeth and lightly brushing for a couple of minutes. Extreme caution should be exercised with this method as the high acidity of lemon can easily damage the enamel, much more so if it is not promptly rinsed out completely with warm water.[citation needed]
A whitening toothpaste can be made by mixing one part baking soda with two parts of hydrogen peroxide. While some cheaper commercial whitening toothpastes have baking soda (sodium bicarbonate) as the whitening ingredient, it is not recommended to use a baking soda-based toothpaste daily for long periods.[citation needed]
[edit]Risks
Side effects of teeth bleaching include, but are not limited to:
- Chemical burns from gel bleaching (if a high-concentration oxidizing agent contacts unprotected tissues, which may bleach or discolor mucous membranes), sensitive teeth
- Overbleaching known in the profession as "bleached effect", particularly with the intensive treatments (products that provide a large change in tooth colour over a very short treatment period, e.g., 1 hour)
- Pain if you have "sensitive teeth" caused by open dentinal tubules.
- Risk of increased hot/cold sensitivity.
- Risk of bleachorexia (An unhealthy obsession with whitening one's teeth)
A recent study by Kugel et al. showed that nearly half the initial change in color provided by an intensive in-office treatment (i.e., 1 hour treatment in a dentist's chair) may be lost in seven days.[12] Rebound is experienced when a large proportion of the tooth whitening has come from tooth dehydration (also a significant factor in causing sensitivity).[13] As the tooth rehydrates, tooth color 'rebounds' back toward where it started.[14]
Home tooth bleaching treatments can very slightly reduce tooth enamel.[15]
The side effects that occur most often are a temporary increase in tooth sensitivity and mild irritation of the soft tissues of the mouth, particularly the gums.[16] Tooth sensitivity often occurs during early stages of the bleaching treatment. Tissue irritation most commonly results from an ill-fitting mouthpiece tray rather than the tooth-bleaching agent. Both of these conditions usually are temporary and disappear within 1 to 3 days of stopping or completing treatment. Individuals with sensitive teeth and gums, receding gums and/or defective restorations should consult with their dentist prior to using a tooth whitening system. People who are sensitive to hydrogen peroxide (the whitening agent) should not try a bleaching product without first consulting a dentist. Also, prolonged exposure to bleaching agents may damage tooth enamel. This is especially the case with home remedy whitening products that contain fruit acids.
Tooth whitening does not usually change the color of fillings and other restorative materials. It does not affect porcelain, other ceramics, or dental gold. However, it can slightly affect restorations made with composite materials, cements and dental amalgams. Tooth whitening can restore color of fillings, porcelain, and other ceramics when they become stained by foods, drinks, and smoking, among other activities.[citation needed]
Bleaching is not recommended in children under the age of 16. This is because the pulp chamber, or nerve of the tooth, is enlarged until this age. Tooth whitening under this condition could irritate the pulp or cause it to become sensitive. Tooth whitening is also not recommended in pregnant or lactating women.
[edit]Agents
Various chemical and physical agents can be used to whiten teeth. Toothpaste typically has small particles of silica, aluminum oxide, calcium carbonate, or calcium phosphate to grind off stains formed by colored molecules that have absorbed onto the teeth from food. Unlike bleaches, whitening toothpaste does not alter the intrinsic color of teeth.
Bleaching solutions contain peroxide, which bleaches the tooth enamel to change its color.[17] Off-the-shelf products typically rely on a carbamide peroxide solution varying in concentration from 10% to 44%. Bleaching solutions may be applied directly to the teeth, embedded in a plastic strip that is placed on the teeth or use a gel held in place by amouthguard.
Peroxide based over-the-counter bleaching products have the potential to generate free radicals. Free radicals are known to be capable of reacting with proteins, lipids and nucleic acids, causing cellular damage; because of the potential of hydrogen peroxide to interact with DNA, concerns with carcinogenicity of hydrogen peroxide have been raised, although these concerns so far have not been substantiated through research.[18][19][20]
Studies have shown that hydrogen peroxide is an irritant and also cytotoxic. At concentrations of 10% or higher, hydrogen peroxide is potentially corrosive to mucous membranes or skin, and can cause a burning sensation and tissue damage.[18]
The US FDA only approves gels that are under 6% hydrogen peroxide or 16% or less of carbamide peroxide. The Scientific Committee for Consumer Protection of the EU also consider gels containing higher concentrations than these to be unsafe.[citation needed]
But there are also a non-peroxide products[21] out in the market that can help you to whiten your teeth.[22]
[edit]Criticism
Over many years clinical research associates (CRA) have studied the effect of light and heat on bleaching. The latest of their studies was published in the March 2003 CRA Newsletter,[citation needed] in which they reported on the characteristics of several in-office bleaching systems using light. The following quote includes part of the CRA conclusions from that newsletter: "Use of lights according to the manufacturer's directions did not improve whitening for any system tested." Systems tested in the CRA study were: LaserSmile, LumaArch, Niveous, Opalescence Xtra Boost, PolaOffice, Rembrandt 1 Hour Smile-Whitening Program, and Zoom. Tests on BriteSmile have not yet been completed. In these studies, light use did not speed or increase the bleaching over the use of bleaching chemicals alone. The slight difference in tooth color observed as a result of bleaching with lights and hydrogen peroxide versus bleaching with hydrogen peroxide alone appears to be temporary and caused by the light's dehydration and heating of the teeth. After a few days to weeks, there appears to be no significant shade difference between teeth bleached with lights and those bleached without lights. Although research varies as to the effectiveness of bleaching using lights, many of the lights used for in-office bleaching appear to be primarily a psychological factor for the patient
