15012973 bleaching of ally treated teeth

8/13/2019 15012973 Bleaching of Ally Treated Teeth

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INTERNATIONAL ISLAMIC UNIVERSITY

MALAYSIA KULLIYYAH OF DENTISTRY

BLEACHING OF ENDODONTICALLY TREATED TEETH

Bleaching Procedure

SHAWFEKAR BTE HJ ABDUL HAMID1/29/2009

It is a well known fact, that a tooth loses its natural color after removal of the pulp. This is

due to dehydration of the tooth substance with consequent loss of translucency. Bleaching of

a discolored pulpless tooth is possible when the discoloration is due to products of pulp

decomposition, or food debris producing organic products, which gain access to the dentinaltubules, or to chromogenic bacteria. When the discoloration is due to metallic salts, bleaching

is more difficult or even impossible. Discoloration of the tooth can be noticed several month s

after death of the pulp or treatment of the tooth, due to slow formation of color-producing

compounds. Traumatic injury of a tooth may cause rupture of the blood vessels in the pulp

with diffusion of blood into the dentinal tubules. Such teeth can be noticed a dark pinkish

immediately after accident, turning to a pinkish-brown some days afterward or even after the

pulp removed.


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BLEACHING OF ENDODONTICALLY TREATED

TEETH

It is a well known fact, that a tooth loses its natural color after removal of the pulp. This isdue to dehydration of the tooth substance with consequent loss of translucency. Bleaching

of a discolored pulpless tooth is possible when the discoloration is due to products of pulp

decomposition, or food debris producing organic products, which gain access to the

dentinal tubules, or to chromogenic bacteria. When the discoloration is due to metallic

salts, bleaching is more difficult or even impossible. Discoloration of the tooth can be

noticed several month s after death of the pulp or treatment of the tooth, due to slow

formation of color-producing compounds. Traumatic injury of a tooth may cause rupture

of the blood vessels in the pulp with diffusion of blood into the dentinal tubules. Such teeth

can be noticed a dark pinkish immediately after accident, turning to a pinkish-brown some

days afterward or even after the pulp removed.

The principal causes of discoloration are:1. Decomposition of pulp tissue2. Excessive hemorrhage following pulp removal3. Trauma4. Medicaments5. Filling materials6. Tetracycline group of antibiotics

STUDY QUESTIONS FOR 2006 ORAL EXAMINATION:

1. Discuss the various types of bleaching, rationale for each, indications/contraindications.2.

Discuss nonvital bleaching technique steps/specifics (duration leave in, etc), andmaterials used.

3. Discuss the possible complications associated with nonvital bleaching.

Indications for Nonvital Bleaching

o Intrinsic (intracoronal) discoloration of pulp chamber origin Endodontically treated teeth Teeth with necrotic pulps Teeth with vital pulps

Contraindications for Nonvital Bleaching

o Superficial (extrinsic) stainso Extensively restored or broken down teetho Severe dentin losso Stains associated with hypoplastic enamel defectso Inadequate endodontic therapy


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Retreat prior to nonvital bleaching!o Previous bleaching without success

Etiology/Prevention of Single-Tooth, Intrinsic Discoloration Defects

Calcific metamorphosis

The yellow discoloration of calcific metamorphosis is usually correctable with

nonvital bleaching. The endodontic therapy performed after canal systemobliteration can be difficult however, and prone to procedural mishaps, especially

radicular gouging and perforation, or non-discovery of the canal. Advise thepatient with severe calcific metamorphosis that efforts to endodontically treat and

bleach an asymptomatic, pulpally vital tooth could result in a root-end surgery orloss of the tooth!

Pulpal hemorrhage due to traumaEven following pulpal vascular disruption and hemorrhage, the pulp may remainvital. Extravasated red blood cells undergo hemolysis and release hemoglobin.

The released hemoglobin breaks down to form several compounds (e.g.hemosiderin), which have the capacity to stain dentin a brownish-red color.

Hemorrhage following pulp extirpation

When canal hemorrhage is not adequately arrested following pulpectomy, bloodcan fill the canal space and remain in contact with dentin for a prolonged time. It

is very important to arrest all hemorrhage prior to access closure! Internal(chamber) and external (cervical extracanal invasive) resorption may result in a

pink coronal hue.

Pulpal necrosis

When bacteria contaminate a necrotic pulp, hydrogen sulfide (produced by thebacteria) combines with the iron released from hemoglobin, to form an iron

sulfide compound. This produces a blackish-gray discoloration. Necrotic debrisleft in pulp chamber recesses during/after endodontic therapy If allowed to

remain, necrotic pulp tissue decomposes and penetrates dentinal tubules. Itimportant to create adequate access openings and thoroughly debride all chamber

recesses, especially pulp horns and fins.

Medications and sealing agents

Some endodontic sealers still contain silver (e.g. Kerrs P ulp Canal Sealer

(EWT) and Tubliseal); however, almost all ZOE sealers (including ourRoth) can cause discoloration, if left in contact with the dentin. For this reason,

in endodontically treated teeth to be definitively restored by a composite access


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closure, obturating materials should not be allowed to remain coronal to theattachment apparatus. Also, these teeth should have their chambers thoroughly

cleaned with a solvent such as isopropyl alcohol or halothane immediatelyfollowing obturation.

Restorative materialsAmalgam should not be used to restore the lingual access of anterior teeth. Thebuccal-lingual dimension of these teeth is too thin, and eventually these teeth will

discolor. Pins can also release metallic ions and cause staining.

Prerequisites for Nonvital Bleaching

Adequate endodontic treatment

Be sure to thoroughly evaluate the adequacy of the existing endodontic treatment

and the periradicular health of each tooth you plan to bleach.

Adequate protective barrier

Walking Bleach Technique

1. Isolate tooth with rubber dam.2. Remove all restorative materials from pulp chamber. It can be difficult to discern

composite restorative materials from tooth structure. If all composite is not removed

from the dentin, bleaching results will be suboptimal.3. Remove small amount of the highly discolored dentin from chamber. Let the

chemicals do the bulk of the work.4. Clean chamber with halothane or chloroform; wash out with sterile water.5. Place a protective base (at least 2 mm thick) over GP to the level of the proximal

CEJs.

6. Place thick paste of sodium perborate and water into chamber (wet sandconsistency).

7. Clean margins of access opening. Cotton is unnecessary.8. Place temporary restoration. Use Cavit, IRM or a GIC. TERM leaks and

should not be used. If occlusion permits, bulk the temporary material into a slightconvex form.

9. Advise patient to avoid function on temporary restoration.10.Examine tooth in 3-5 days. Assess shade change and discuss progress with patient.

Repeat procedure if bleaching result is partially successful, yet not adequate. Restoreif adequate. Remember, a slight overbleach is recommended by many clinicians,

because there may be a partial shade relapse over the first few weeks.


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Restoration of Lingual Access

Retain translucency of crown

Place protective base only to CEJ and not into chamber space

Use solvent to dissolve/remove unset sealer immediately post-obturation

Use the lightest shade of composite resin

Ensure optimal marginal adaptation of material

Seal is critical to prevent re-discoloration

Postbleaching Cervical Resorption

This type of inflammatory external root resorption was first reported in 1979. It is very

destructive and occurs primarily in the proximal CEJ regions. There is clearly a

relationship between internal bleaching of teeth and the stimulation of periodontalligament cells to resorb tooth structure. The exact etiology is unknown, althoughdiffusion of hydrogen peroxide through patent dentinal tubules is believed to be the major

factor. Other precipitating factors are theorized to be heating of the hydrogen peroxideand the original trauma. In approximately 10% of teeth, the enamel and cementum do

not meet, thus allowing patent dentinal tubules to be exposed to the periodontal ligament.Also, traumatized teeth sustain cemental tears. It is possible that these teeth allow

diffusion of chemicals through dentinal tubules to the PDL.

To be safe, the best prescription for prevention is:1. Avoid acid etching of chamber.

2. Avoid use of heat, if possible.3. Avoid use of 30-35% hydrogen peroxide, if possible (use water or

anesthetic).4. Ensure a good quality obturation exists and place a protective base.

5. Recall (with radiograph) at 1 and 2 years post-bleaching.

Treatment of this problem is complicated. Placement of calcium hydroxide to arrest theprocess, surgical repair and orthodontic extrusion/restoration have been described as

efforts to retain these teeth affected by postbleaching cervical resorption. Alterations ofbleaching techniques (eliminating 30% hydrogen peroxide, placing a protective base over

GP) have been proposed to minimize resorption occurrence. Postbleaching resorption

should be discussed as a part of the informed consent.


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Bleaching Prognosis

o The immediate results are oftentimes excellent. A very slight overbleach is indicated, in anticipation of short-term relapse.

o Color stability Over the long term, partial relapse is expected. This compromise is acceptable to most patients. Some will require rebleaching.

o Resorption Incidence is ~2-7% when no protective base used; near 0% with a base.

o Recall Resorption is often not evident until one year or longer post-bleaching.

Informed Consent

It is important to discuss the bleaching process and its prognosis with your patient.

Patients are usually excited about bleaching, because they know little and have highexpectations. Dont promise too much! Discuss a realistic prognosis, based on the

patients degree/duration of discoloration. Shade improvements may be minimal or maynot occur at all. Several appointments may be required for a walking bleach. Thin

temporary restorations are often lost. There is the strong likelihood that some relapsewill occur over the long term. Existing root canal therapy may require retreatment, due

to technical deficiencies. Cervical root resorption is a risk. RCT performed in support ofbleaching only (e.g. calcific metamorphosis) may result in a significant misadventure

(e.g. radicular perforation), a root-end surgical procedure, or loss of the tooth! Well-informed patients are more satisfied at the conclusion of therapy than those less informed.

Treatment alternatives to nonvital bleaching exist: no treatment, laminate veneer, or a fullcrown.

Bleaching

Teeth bleaching to whiten teeth:

There are many products currently on the market that promise whiter, brighter teeth. TheAmerican Dental Association (ADA) states that if you are a candidate for a procedure, yourdentist may suggest a procedure that can be done in a dental office. Other options include at-

home products, which may be dispensed by your dentist or purchased over-the-counter. But,dental professionals, and the ADA, issue a word of caution about the improper use of such over-


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the-counter products, as they are sometimes too abrasive and can damage the teeth with extendeduse.

The ADA describes "whitening" as any process that will make teeth appear whiter, using one of

two approaches. A product can bleach the tooth, therefore changing the natural tooth color. A

bleach contains peroxide that helps remove deep and surface stains. However, a non-bleachingwhitening product contains substances that help remove surface stains only.

Who may benefit from teeth bleaching?

Most beneficial Moderately beneficial Not recommended

age spots

yellow or orange spotting onteeth caused by coffees, teas,

berries and other foods, or

smoking

gray or brown stains

caused by fluorosis

(excessive intake of

fluoridated water)

gray stains caused by

smoking and/or the use of

certain medications

overly-sensitive teeth

persons with a gum ormouth disease (periodontal

disease or oral cancer)

persons with worn tooth

enamel

What are some different teeth-whitening methods?

The dentist will use either an in-office bleaching system or laser bleaching while you are in the

dental chair. Some patients, however, choose dentist-supervised at-home bleaching, which ismore economical and, in many cases, provides the same results.

One option for at-home bleaching involves using a custom-made mouthguard that can be worncomfortably while you are awake or sleeping. The mouthguard is so thin that you should even be

able to talk and work while wearing it. Some bleaching systems recommend bleaching your teethfrom two to four hours a day - these usually take three to six weeks to complete and work best on

patients with sensitive teeth. Other systems recommend bleaching your teeth at night, while yousleep, which may only take 10 to 14 days to complete.

Recently, more over-the-counter products are available that offer simple whitening solutions.

However, they may not provide the dramatic improvement that a professional treatment optionoffers.

Teeth bleaching side effects and health risks:

The American Dental Association has granted its seal of approval on some teeth whiteningproducts. Consult your dentist regarding which products are most effective and safe to use.

Gum irritation and increased tooth sensitivity are the most common side effects of teeth

bleaching. However, each individual may experience side effects differently.


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Bleaching of a Tooth: Some people experience a graying of a tooth that either has been injuredor had a root canal. You can have the tooth bleached internally so it will match the color of your

others. It would remove the filling material at the back of the tooth and over a series ofapproximately 3 appointments, then it will place a special bleaching material inside the tooth.

Once the tooth color matches that of your other teeth, you can return to your general dentist for a

permanent filling. What a wonderful way to keep your smile looking healthy!


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Following trauma, tooth discoloration is very common. The discoloration comes from thebleeding inside the pulpal chamber. The dentin becomes stained as the blood gets into the

dentinal tubules and trapped in the pulp horns. The first step in restoring the natural color to thetooth is good endodontic therapy with adequate removal of the stained facial dentin and complete

removal of the pulp horns. If the natural tooth color is not restored with this procedure, then the

additional treatment of non-vital internal bleaching is indicated.

A common error is incomplete removal of the pulpal horns due to a small apically placed access.

Care must be taken to remove stained dentin and pulpal horns while trying to preserve maximumtooth structure.

The following case shows how to "get the stain out".

Tooth #9 & #10 sustained traumatic injury.

Note the discoloration on #9.


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After opening the access, staining can be seen in #9. #10 looks normal.

A round bur is used to remove the stain from the facial surface of the pulp chamber. Careful

examination with magnification reveals remaining stain in pulp horns. The access is carefullyrefined to remove stain from pulp horns while keeping access as conservative as possible.


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Following removal of rubber dam, the change in coloration is noted. Patient is informed that thetooth is dehydrated and will continue to change color until rehydration is complete. At that time,

evaluation can be made if additional internal bleaching procedures will be needed.

Obturation completed.

Adequate endodontic therapy alone will often resolve the patient's esthetic concerns. Non-vital

bleaching is a good adjunct for teeth requiring additional whitening.


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15012973 bleaching of ally treated teeth

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