Dental BleachingStudent Graduation Research

Dental Bleaching

By StudentsMohammed Sa’ad Al NuaimiAbeer Farman Al Dulayme

Dhuha Wael Al JanabyDuaa’ Sa’ad Al Zubaide

 Supervised by

Dr. Zena Tariq Al AniBDS. MSC. Conservative Department

Acknowledgement

We are honored to dedicate this scientific research to :

His highness minster of the higher education and scientific research

The dean of the college Dr. Ali Za’lan Ne’ma

The Head of the Dentistry Department Dr. Mohammed Al yaserie

The Head of conservative department Dr. Zena Tariq Al ani

The senior of the conservative clinic Dr. Hadeel Kareem Hamza

And our beloved families.

Abstract

Personal appearance is important in today’s society. Many products and procedures, including tooth whitening, are being marketed to the public as a method for enhancing personal appearance. People frequently ask dental professionals whether tooth whitening is effective and whether it would be appropriate treatment for them. In order to field the public’s questions and promote informed choices, dentist must be knowledgeable about tooth whitening products and procedures .

A Medline search over a 25-year period was conducted to locate studies about the efficacy, effects and biological safety of tooth whitening products and procedures. The search resulted in approximately 60 articles. Additional articles were obtained through article references. The objective of the research was to prepare a literature review on tooth whitening.

The literature revealed that teeth can be bleached approximately two shades but a second follow-up treatment is usually required after one to three years. In-office and at-home bleaching techniques were studied. Bleaching materials were found to adversely affect dental hard tissues. Some evidence was provided to support the view that short-terms of tooth whitening on tooth pulps appear to be reversible Long-term effects of bleaching agents on hard and soft tissues remain unknown. Evidence shows there is a reduction in enamel-composite resin bond strength in teeth treated with peroxide agents though the clinical significance of this bond reduction is not known. Safety issues concerning the impact of peroxide agents on human oral mucosal antioxidant defense mechanisms were identified.

The writers’ research found little consensus in much of the research. A number of significant areas of concern have not yet been thoroughly investigated. Long-term scientific human studies are recommended to address the unanswered questions about the efficacy, effects and biological safety of tooth whitening.

List of Subjects

Acknowledgement

Abstract

Introduction

Causes of Tooth Discoloration

The mechanism of action of bleaching

Factors affect tooth bleaching

Types of dental bleaching

Non-vital bleaching

Vital bleaching or home bleaching

Light-accelerated bleaching

Natural methods

Bleaching Materials

Safety Concerns with Tooth Bleaching Materials 

Summary  

List of Figures 

Fig 1 A Stained teeth with smocking habit patient 

  B After bleaching process although the use of ceramic alternative to improve lateral incisor

  C Stained teeth with medications induced tooth discoloration

  D After a combination of home and office tooth bleaching the result is brighter teeth.

Fig 2   Common oxidation processes associated with bleaching teeth. The saturation point at which the optimal amount of bleaching has occurred is located in the middle of the diagram. 6

Fig 3   pre- and postoperative colour of a darkened nonvitaltooth following trauma. The appearance improved greatly after 2 weeks. 

Fig 4   White opaque lesions on the two central incisors

List of Tables

Table 1 : Causes of tooth discoloration

 

List of Abbreviation

OTC Over the counter

FDA U.S. Food and Drug Administration

ADA American Dental Association

MIH melanotropin release-inhibiting hormone

Introduction

Over the past two decades, tooth whitening or bleaching has become one of the most popular esthetic dental treatments (Note: this paper uses the terms "whitening" and “bleaching," interchangeably). Since the 1800s, the initial focus of dentists in this area was on in-office bleaching of non-vital teeth that had discolored as a result of trauma to the tooth or from endodontic treatment. By the late 1980s, the field of tooth whitening dramatically changed with the development of dentist-prescribed, home-applied bleaching (tray bleaching) and other products and techniques for vital tooth bleaching that could be applied both in the dental office and at home.

The tooth whitening market has evolved into four categories: professionally applied (in the dental office); dentist-prescribed/dispensed (patient home-use); consumer-purchased/over-the-counter (OTC) (applied by patients); and other non-dental options. Additionally, dentist-dispensed bleaching materials are sometimes used at home after dental office bleaching to maintain or improve whitening results.

Consumer whitening products available today for home use include gels, rinses, chewing gums, toothpastes, paint-on films and strips. The latest tooth whitening trend is the availability of whitening treatments or kits in non-dental retail settings, such as mall kiosks, salons, spas and, more recently, aboard passenger cruise ships. Non-dental whitening venues have come under scrutiny in several states and jurisdictions, resulting in actions to reserve the delivery of this service to dentists or appropriately supervised allied dental personnel.

Current tooth bleaching materials are based primarily on either hydrogen peroxide or carbamide peroxide. Both may change the inherent color of the teeth, but have different considerations for safety and efficacy. In general, most in-office and dentist-prescribed, at-home bleaching techniques have been shown to be effective, although results may vary depending on such factors as type of stain, age of patient, concentration of the active agent, and treatment time and frequency. However, concerns have remained about the long-term safety of unsupervised bleaching procedures, due to abuse and possible undiagnosed or underlying oral health problems.

Although published studies tend to suggest that bleaching is a relatively safe procedure, investigators continue to report adverse effects on hard tissue, soft tissue, and restorative materials.1-3 The rate of adverse events from use or abuse of home-use OTC products is also unclear because consumers rarely report problems through the U.S. Food and Drug Administration (FDA) Medwatch system. Based on these factors, the American Dental Association (ADA) has advised patients to consult with their dentists to determine the most appropriate whitening treatment, particularly for those with tooth sensitivity, dental restorations, extremely dark stains, and single dark teeth.4

Additionally, a patient’s tooth discoloration may be caused by a specific problem that either will not be affected by whitening agents and/or may be a sign of a disease or condition that requires dental therapy.

Causes of Tooth Discoloration

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 and phosphate-deficient. Teeth can become stained by bacterial pigments, smoking, food-goods and vegetables rich with carotenoids or xanthonoids. Certain antibacterial medications (like tetracycline) can cause teeth stains or a reduction in the brilliance of the enamel. Ingesting colored liquids like coffee, tea, and red wine can discolor teeth.

The mechanism of action of bleaching

It is also unclear. Bleaching is an oxidation reaction. The enamel to be bleached donates electrons to the bleaching agent.2 Ten per cent carbamide peroxide breaks down to 3% hydrogen peroxide and 7%urea. The hydrogen peroxide metabolizes into water and free radicals of oxygen. These free radicals possess a single electron, which is thought to combine with the chromagens to decolourize or solubize them. 5

Factors affect tooth bleaching

Types of dental bleaching

There are two types of bleaching:

 

vital

Non-vital

 

Both clinical techniques rely upon the action of hydrogen peroxide to change the appearance of the teeth.

 

NON-VITAL BLEACHING

Case Selection

Non-vital teeth that have discoloured as a result of trauma can be successfully bleached, but those with other intrinsic stains such as amalgam or remineralized lesions will be more resistant to colour change. Teeth with minor restorations on the buccal surface – or, ideally, those with only an access cavity present – are the most successfully bleached. Teeth with extensive restorations are usually more effectively treated with crowns. Ideally, the shade of the unbleached tooth should be recorded using a shade guide or clinical photographs before attempting to bleach it.

Clinical Technique

Nutting and Poe8 advocated placing a slurry of sodium perborate and hydrogen peroxide in the access chamber of nonvital teeth, provided that an adequate seal is present both apically and coronally.

They called this the .walking bleach. technique. It is essential (in the view of the author) to ensure that the root treatment is asymptomatic, free from periapical changes and has a good obturation with gutta-percha. Once the root treatment has been completed all the remaining gutta-percha should be removed to below the level of the gingival margin within the radicular canals. It is also important to ensure that the buccal surface of the access cavity is free of restorative material such as composite; although theoretically the bleaching agent can permeate around or through the material, it is more convenient to ensure that the material has been removed at the start. A glass ionomer, zinc phosphate or composite lining should be placed in the radicular part of the root canal below the gingival margin to seal the canal from the bleaching agent. Some practitioners have advocated etching the internal surface of the cavity with a proprietary etchant.

However, Casey and co-workers reported that etching made no difference to the success of bleaching.19 Once the access cavity is clear, 100- volume hydrogen peroxide (obtainable from chemists or hospital pharmacists) is mixed with powdered sodium perborate to produce a damp slurry. The slurry is carried to the tooth, surrounded by a rubber dam, and placed so that it partially fills the pulpal chamber. A cotton wool pellet is then placed on top of the slurry and the access cavity sealed with temporary cement (this can be zinc oxide eugenol, polycarbonate cement, glass ionomer or composite). The patient is reviewed within 2 weeks and the process repeated until the colour is improved to the patient.s satisfaction. Often the site that is most resistant to bleaching is around the cervical margin and onto the root surface. Figure 3 shows the pre- and postoperative colour of a darkened nonvital tooth following trauma. The appearance improved greatly after 2 weeks.

VITAL BLEACHING OR HOME BLEACHINGCase Selection

 

Unlike non-vital bleaching, most cases of vital bleaching involve more than one tooth. Darkening of teeth caused by ageing is possibly one of the more common forms of discoloration of teeth and is successfully treated with vital bleaching. Tetracycline-stained teeth are not as common as they were 10-15 years ago as the medical and dental profession are now fully aware of the implications of prescribing drugs that cause staining during tooth development. However, tetracycline stain can be found in people

born outside the UK. The severity of tetracycline stains can vary from a brown-yellow coloration, which can respond to bleaching, to a blue-black, which traditionally is more resistant. Fluorosis is more commonly found within the UK and can present as white or brown speckles or patches on teeth ( Figure 4). The brown discoloration can be removed by bleaching but the white opacities are more resistant, although bleaching can in some situations reduce the brilliance of the white by merging the colour with the surrounding teeth. More localized discoloration on teeth can occur in any severe childhood illness and may also cause changes in the shape of the teeth due to disruption in the tooth development. For successful bleaching, case selection is extremely important. People perceive colour differently and what appears acceptable to one person may not be to someone else. It is also important to attempt to distinguish with what aspect of

a tooth a patient is dissatisfied. It may be that the relatively darker area around the cervical-gingival margin of a canine is unacceptable to a patient, but once this is explained as a natural phenomenon their concern may be alleviated and treatment becomes unnecessary. Incidentally, this area is also more resistant to changes in

tooth colour by bleaching.

Fig. 4 : White opaque lesions on the twocentral incisors. These could be treated bybleaching but may be more responsive to

acidabrasion or enamel biopsy techniques

followedby localized composite restorations

Clinical Technique

The most commonly referenced vital bleaching products are those containing a 10% solution of carbamide peroxide. This material breaks down to form a 3% solution of hydrogen peroxide and urea. The carbamide peroxide is usually delivered in a viscous gel, which is applied closely to teeth via a custommade vacuum-formed appliance. The

appliance should be well contoured to the gingival margins to reduce the potential for irritation of the gingival tissues and spaced over the teeth that are to be bleached. This spacer is applied to the working model on the teeth that will be bleached and can be a proprietary material or common laboratory product such as die relief or nail varnish. The

thickness of the appliance should be around 2 mm – not so thick that it causes discomfort. In a study by Frazier and Haywood,7 81% of dental schools taught the use of reservoirs and scallops around the gingival margin in the design of the bleaching appliance, whilst only 13% used trays without reservoirs, indicating the popularity of the former technique. Home bleaching products are most successful if the patient applies the

material into the trays for 6-8 hours a day (often overnight) and usually over a period of 3-4 weeks, but different products vary. Frazier and Haywood reported that bleaching was most commonly successful after 2-4 weeks.7 For more intense stains, such as that

found with tetracycline, it may take between 3 and 6 months to reach a successful result. If patients do not add the bleaching agent regularly to the tray there is insufficient time for the hydrogen peroxide to work and they become disappointed, which becomes a

vicious circle and success is unlikely

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.[9] The ideal source of energy should be high energy to excite the peroxide molecules without overheating the pulp of the tooth.[10] 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.

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.[11][12] 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 support and help whitening teeth,[13] 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.

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 Typical whitening gels use some form of peroxide as their active ingredient, and peroxides have no ability to dissolve the proteins that stain the porous surfaces of teeth.

Bleaching Materials

The active ingredient in tooth bleaching materials is per- oxide compounds. While currently a variety of bleaching materialsareavailable,themostcommonlyusedperoxide compounds are hydrogen peroxide, sodium perborate, and carbamide peroxide. Bleaching materials for extra- coronalbleachingmainlycontainhydrogenperoxideand carbamide peroxide, whereas sodium perborate is used for intracoronal bleaching. Both sodium perborate and carbamide peroxide decompose to release hydrogen peroxide in an aqueous medium.

Hydrogen Peroxide

Hydrogen peroxide (H2O2) is used in both in-office and at-home bleaching materials. In-office bleaching materials contain high concentrations of H2O2 (typically 25% to 38%), while the H2O2 concentration in at-home bleaching products usually range from 3% to 7.5%; however, there have been products containing up to 14% H2O2 for home use by patients. H2O2 at high concentration, such as those in the inoffice bleaching materials, is caustic and burns tissues on contact. These materials must be handled with care to avoid their contact with tissues during the handling and bleaching treatment.

 

Sodium Perborate

Sodium perborate (NaBO3) is available in powdered form or as various commercial preparations. When fresh, it contains about 95% perborate, corresponding to 9.9% of the available oxygen. Sodium perborate is stable when dry. In the presence of acid, warm air, or water, however, it decomposes to form sodium metaborate, H2O2, and nascent oxygen. Three types of sodium perborate preparations are available: monohydrate, trihydrate, and tetrahydrate. They differ in oxygen content that determines their bleaching efficacy. Commonly used sodium perborate preparations are alkaline, and their pH depends on the amount of H2O2 released and the residual sodium metaborate.

Sodium perborate is more easily controlled and is safer than concentrated H2O2. Therefore, it is the material of choice in most intracoronal bleaching procedures.

Carbamide Peroxide

Carbamide peroxide (CH6N2O3), also known as urea hydrogen peroxide, exists in the form of white crystals or as a crystallized powder containing approximately 35% H2O2. It forms H2O2 and urea in aqueous solution. It is mostly used in home-use bleaching materials with concentrations ranging from 10 to 30% (equivalent to approximately 3.5% to 8.6% H2O2); however, those containing 10% carbamide peroxide appear to be the most common.

Bleaching preparations containing carbamide peroxide usually also include glycerine or propylene glycol, sodium stannate, phosphoric or citric acid, and flavor additives. In some preparations, carbopol, a watersoluble polyacrylic acid polymer, is added as a thickening agent. Carbopol also prolongs the release of active peroxide and improves shelf life.

Safety Concerns with Tooth Bleaching Materials  

Concerns regarding the safety of all bleaching treatments and products have long existed, but were heightened since the introduction of at-home bleaching.14-15 Discussions in this section focus on peroxides and their use as active ingredients in tooth bleaching materials. Important concerns related to patient examination and diagnoses are addressed elsewhere in this report.

A variety of peroxide compounds, including carbamide peroxide, hydrogen peroxide, sodium perborate and calcium peroxide, have been used as active ingredients for bleaching materials; however, essentially all extracoronal bleaching materials currently available for whitening of vital teeth in the United States contain carbamide peroxide and/or hydrogen peroxide. Recently, products containing chlorine dioxide were introduced in the United Kingdom, but there is no evidence that tooth bleaching products using chlorine dioxide as the active ingredient are safer than peroxide-based materials. In fact, safety concerns have been documented with chlorine dioxide and its use for tooth bleaching treatment due to the low pH of the material and resultant tooth etching.16

Most OTC bleaching products are hydrogen peroxide-based, although some contain carbamide peroxide. Carbamide peroxide decomposes to release hydrogen peroxide in an aqueous medium: ten percent carbamide peroxide yields roughly 3.5% hydrogen peroxide. In-office bleaching materials contain high hydrogen peroxide concentrations (typically 15-38%), while the hydrogen peroxide content in at-home bleaching products usually ranges from 3% to 10%; however, there have been home-use products containing up to 15% hydrogen peroxide.

Safety issues have been raised regarding the effects of bleaching on the tooth structure, pulp tissues, and the mucosal tissues of the mouth, as well as systemic ingestion. Regarding mucosal tissues, safety concerns relate to the potential toxicological effects of free radicals produced by the peroxides used in bleaching products. 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 and co-carcinogenicity of hydrogen peroxide have been raised, although these concerns so far have not been substantiated through research.14,17,18 However, studies have shown that hydrogen peroxide is an irritant and also cytotoxic. It is known that at concentrations of 10% hydrogen peroxide or higher,

the chemical is potentially corrosive to mucous membranes or skin, and can cause a burning sensation and tissue damage.14,19,20 The amount of products applied during office bleaching treatment and other formulation variables can change the potential to cause damage. However, severe mucosal damage can occur if gingival protection is inadequate with high strength tooth whitening products. Clinical studies have also observed a higher prevalence of gingival irritation in patients using bleaching materials with higher peroxide concentrations.21,22

Data accumulated over the last 20 years, including some long-term clinical study follow up23, 24; indicate no significant, long-term oral or systemic health risks associated with professional at-home tooth bleaching materials containing 10% carbamide peroxide (3.5% hydrogen peroxide). However, these data were collected from studies which include examinations by dental professionals, and there is no safety evidence on bleaching materials that do not involve such examinations by dental professionals, regardless of hydrogen peroxide concentration or application venue. Additionally, consumers are not generally aware of how to report adverse events through FDA’s Medwatch system. If a licensed dental professional is not consulted when patients use OTC bleaching products, adverse effects due to product abuse may go unreported.

Regarding hard tissues, transient mild to moderate tooth sensitivity can occur in up to two-thirds of users during early stages of bleaching treatment.25 Sensitivity is generally related to the peroxide concentration of the material and the contact time; it is most likely the result of the easy passage of the peroxide through intact enamel and dentin to the pulp during a five- to 15-minute exposure interval. However, there have been no reported long-term adverse pulpal sequellae when proper techniques are employed. The incidence and severity of tooth sensitivity may depend on the quality of the bleaching material, the techniques used, and an individual’s response to the bleaching treatment methods and materials. To date, there is little published evidence documenting adverse effects of dentist-monitored, at-home whiteners on enamel, but two clinical cases of significant enamel damage have been reported, apparently associated with the use of OTC whitening products.26,27 This damage may be related to the low pH of the products and/or overuse.

In vitro studies suggest that dental restorative materials may be affected by tooth bleaching agents.28 These findings relate to possible physical and/or chemical changes in the materials, such as increased surface roughness, crack development, marginal breakdown, release of metallic ions, and decreases in tooth-to-restoration bond strength. Such findings have not appeared in clinical reports or studies.

To address the safety of bleaching materials, the ADA convened a panel of experts in 1993. The ADA subsequently published its first set of guidelines for evaluating peroxide-containing tooth whiteners.29 These guidelines have been revised periodically.

In March 2005, the European Scientific Committee on Consumer Products (SCCP) concluded the following: ―The proper use of tooth whitening products containing >0.1 to 6.0% hydrogen peroxide (or equivalent for hydrogen peroxide-releasing substances) is considered safe after consultation with and approval of the consumer's dentist.

SCCP, in January 2008, again recommended that up to 6% hydrogen peroxide is a safe limit to use for at-home tooth bleaching; however, it did not recommend use of such products without dental consultation.30

In summary, available data indicate that extracoronal bleaching treatment in the dental office or at home may cause short-term tooth sensitivity and/or gingival irritation. More severe mucosal damage is possible with high hydrogen peroxide concentrations. While available evidence supports the safety of using bleaching materials of 10% carbamide peroxide (3.5% hydrogen peroxide) by dental professionals, there are concerns with the use of at-home bleaching materials with high hydrogen peroxide concentrations. Studies designed specifically to assess the long-term safety of high hydrogen peroxide concentration in at-home bleaching materials are needed, especially for repeated use of these products. There appears to be insufficient evidence to support unsupervised use of peroxide-based bleaching materials.

Similar to other dental and medical interventions, questions have been raised about the safety of tooth whitening treatments during pregnancy. In the absence of such evidence, clinicians may consider recommending that tooth whitening be deferred during pregnancy.

The safety of tooth bleaching for children and adolescents is also a consideration. More research is needed to establish appropriate use and limitations for these patients. However, bleaching is a conservative approach compared with restorative options when tooth discoloration causes significant concern. If possible, delaying treatment until after permanent teeth have erupted is recommended, as is use of a custom-fabricated bleaching tray to limit the amount of bleaching gel.31 Close professional and parental/guardian supervision are needed to maximize benefits and minimize adverse effects and overuse.

Summary

Tooth bleaching is one of the most conservative and cost-effective dental treatments to improve or enhance a person’s smile. However, tooth bleaching is not risk-free and only limited long-term clinical data are available on the side effects of tooth bleaching. Accordingly, tooth bleaching is best performed under professional supervision and following a pre-treatment dental examination and diagnosis.

In consultation with the patient, the most appropriate bleaching treatment option(s) may be selected and recommended based on the patient’s lifestyle, financial considerations, and oral health. Patients considering OTC products should have a dental examination, and should be reminded that they may unknowingly purchase products that may have little or no beneficial effect on the color of their teeth and may also have the potential to cause harm.

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3- Goldberg M, Grootveld M, Lynch E. Undesirable and adverse effects of tooth-whitening products: a review. Clin Oral Invest 2010;14:1-10.

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5- Nathoo, S.A.: The chemistry and mechanisms of extrinsic and intrinsic discoloration. JADA 128: pp. 6S–9S, 1997.

6- Tooth lighting ADEPT Robert 1991:2(1):1-24.)

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10- "Accepted Over-the-Counter Products". Retrieved 2010-07-05.

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12- "Foods That Whiten Teeth Naturally". Retrieved 12-02-2012.

13- "How to Whiten Your Teeth Naturally #2". May 20, 2011. Retrieved 12-02-2012.

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15- Sulieman MA. An overview of tooth-bleaching techniques: chemistry, safety and efficacy. Periodontol 2000. 2008; 48:148-69.

16- Greenwall L. The dangers of chlorine dioxide tooth bleaching. Aesthetic Dentistry Today 2008; 2:20-22.

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18- Munro IC, Williams GA, Heymann HO, Kroes R. Use of hydrogen peroxide-based tooth whitening products and the relationship to oral cancer. J Esthet and Rest Dent 2006; 18:119-125.

19- 12 Agency for Toxic Substances and Disease Registry. Medical Management Guidelines for Hydrogen Peroxide (H2O2). September 2007. Retrieved August 26, 2009, from http://www.atsdr.cdc.gov/MHMI/mmg174.html.

20- Scientific Committee on Consumer Products (European Commission). Opinion on hydrogen peroxide in tooth whitening products. SCCP/0844/04, March 15, 2005.

21- Gerlach RW, Zhou X. Comparative clinical efficacy of two professional bleaching systems. Compend Contin Educ Dent 2002; 23: 35-41.

22- Kugel G, Aboushala A, Zhou X, Gerlach RW. Daily use of whitening strips on tetracycline-stained teeth: comparative results after 2 months. Compend Contin Educ Dent 2002; 23:29-34.

23- Ritter AV, Leonard RH, St. Georges AJ, Caplan DJ, Haywood VB. Safety and stability of nightguard vital bleaching: 9-12 years post-treatment. J Esthet Restor Dent 2002; 14275-285.

24- Leonard RH Jr, Bentley C, Eable JC, Garland GE, Knight MC, Phillips C. Nightguard vital bleaching: a long-term study on efficacy, shade retention, side effects, and patients’ perceptions. J Esthet Restor Dent 2001; 13:357-369

25- Hasson H, Ismail AI, Neiva G. Home-based chemically-induced whitening of teeth in adults. Cochrane Database of Systematic Reviews 2006, Issue 4.

26- Cubbon T, Ore D. Hard tissue and home tooth whiteners. CDS Review 1991;June:32-35.

27- Hammel S. Do-it-yourself tooth whitening is risky. US News and World Report 1998; April 2:66.

28- Al-Salehi SK. Effects of bleaching on mercury ion release from dental amalgam. J Dent Res 2009; 88:239-43.

29- American Dental Association. Guidelines for the acceptance of peroxide-containing oral hygiene products. J Am Dent Assoc 1994; 125:1140-1142.

30- Scientific Committee on Consumer Products (European Commission). Opinion on hydrogen peroxide, in its free form or when released, in oral hygiene products and tooth whitening products. SCCP/1129/07, December 18, 2007.

31- Lee SS, Zhang W, Lee DH, Li Y. Tooth whitening in children and adolescents: a literature review. Pediatric Dentistry 2005;27:362-368.

الخالصة

المسوقة المنتجات من الكثير وبجود ابتسامته وخصوصا الحالي بالوقت المهمه االشياء من يعتبر االنسان مظهراالبتسامة عند النفس في الثقة تزداد وبالتالي بيضاء االسنان مظهر على الحفاظ في تساعد اللتي االسنان . لتبيض

يجب " " ولذلك ؟ عالج افضل هو وهل ومهم صحي امر االسنان تبيض � فعال هل االنسان خبراء يسألون عادة الناساستخدامها وكيفية االسنان تبيض وطرائق ومنتجات التساؤالت هذه اجوبة جميع معرفة االسنان طبيب . على

مدار على اجريت ذلك 25لقد عن نتج وقد المجال هذا في االبحاث من العديد اساس 60سنة انشاء هدفها مقالاالسنان لتبيض .تعريفي

ثالث ) ( الى سنة بعد الالحقة الجلسة وتتم درجتين بقدر تبيضها لونها تغيير يمكن االسنان ان الدراسات اضهرت.سنوات

. المده نظريه بدعم قامت الدالئل بعض لألسنان الصلبة االنسجة على سلبيا تؤثر انها وجدت االسنان تبيض موادمعرفة يتم لم االسنان لتبيض الطويلة والمدة السن لب انسجة على عكسي بشكل تؤثر األسنان لتبيض القصيرة

االسنان انسجة على تاثيرها .طبيعة

والحشوات السن انسجة بين التماسك قوة وتقلل سلبية بصورة يؤثر االسنان تبيض مواد ان اثبتت الدالئل بعضبيرأوكسايد " ال مادة اتسعمال عند ." الضوئية

. الطويلة الدراسات اختصت وقد الحاالت على الكشف خالل من المقلقة القليلة الحاالت من عدد الباحث وجد وايضااالسنان لتبيض الحية االنسجة سالمة و وتأثير كفائة بخصوص عنها االجابة يتم لم اللتي لالسئلة اجوبة عن للبحث

العلمي والبحث العالي التعليم وزارةاالسنان \ طب قسم الجامعة اليرموك كلية

تخرج بحث 

االسنان تبيضالفاضلة الدكتورة باشراف

العاني. طارق زينة داالسنان . . معالجة قسم ماجستير بكلوريوس

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