Ce 1 - matis special apr

Tray Whitening: What
the Evidence Shows
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In recent years, many dental professionals have changed their philos-
Bruce A. Matis, DDS, MSD
ophy regarding the use of trays with at-home bleaching regimens.
However, facts do not change—and successful vital tooth bleaching
still occurs only when tooth surfaces are in direct contact with the
appropriate concentration of active whitening agent for a specific
amount of time. Because the science of tooth whitening is still in its
infancy—this article reviews a series of remaining questions regarding
vital tooth bleaching based on current scientific information and
research findings on products using trays.
Among the most widely accessible and relatively easy means of achieving a more youthful appearance is vital tooth bleaching.
While the value of whiter teeth is clearly increasing among the gen- eral population, the philosophy of many dental professionals regarding thethe use of customized trays with dentist-dispensed at-home bleaching agentshas changed within the past 3 years, although the science behind the treat-ment has not.
As previously addressed by this author in an article from the first Learning Objectives:
Symposium on Tooth Whitening,1 the facts do not change. Successful vital tooth bleaching only occurs when any active gel of an appropriate concen- tration is in contact with tooth surfaces for a reasonable duration. Exposure time and concentration of tooth whitening gel continue to be the two most important elements of successful bleaching. Realistically, the science of tooth whitening is still in its infancy, and many questions and concerns remain. As more information about tooth bleaching becomes available, it either strengthens existing concepts or allows us to make appropriate modifications to conform to new findings.
Among the concerns regarding tooth bleaching are what concentration of active ingredient is best, the effects of bleaching on the pulp of vital using 10% carbamide per-oxide and compare how teeth, whether actual concentration is consistent with manufacturer claims, the usefulness of reservoirs, and the appropriate duration of bleaching regi- mens. Additionally, questions regarding the efficacy of tray bleaching com- pared to in-office bleaching, as well as tray bleaching against stubborn stains, require further investigation. While there are many opinions on eachof these items, this article addresses these questions and concerns in termsof current scientific information and research findings.
The Case for 10% Carbamide Peroxide
The American Dental Association (ADA) established guidelines for the acceptance of at-home tooth whitening agents.2 When these guidelineswere initially formulated 9 years ago, the ADA carefully selected tests thatproducts had to undergo and satisfactorily complete before they could beaccepted as “safe” and “effective” Safe, as defined by the ADA, does notmean clinically safe, but biologically safe. The same safety standards thatwere implemented at that time are still in effect today. Efficacy levels must Compendium / April 2003
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Table 1—Tray-Used Dentist-Dispensed Products With Their Assayed Concentrations
Carbamide Peroxide
Manufacturer
or Hydrogen Peroxide
Concentrations
Rembrandt® Xtra Comfort Carbamide Peroxide aAccess Dental, San Diego, CA 92117; (858) 496-0574bIvoclar Vivadent, Amherst, NY 14228; (800) 533-6825cDiscus Dental, Inc, Culver City, CA 90232; (800) 422-9448dSDI Inc, Bensenville, IL 60106; (800) 228-5166eSpectrum Dental, Inc, Culver City, CA 90232; (800) 556-7606fDENTSPLY Professional, York, PA 17404; (800) 989-8826gOmnii Oral Pharmaceuticals, West Palm Beach, FL 33409; (800) 445-3386hPatterson Dental, St. Paul., MN 55120; (800) 328-5536iUltradent Products, Inc, South Jordan, UT 84095; (800) 522-5512jTemrex Corp, Freeport, NY 11520; (800) 645-1226k3M ESPE, St. Paul, MN 55144-1000; (800) 634-2249lDen-Mat Corp, Santa Maria, CA 93456; (800) 445-0345mPremier Dental Producs, Plymouth Meeting, PA 19462; (888) 773-6872 *only available as Rembrandt® Lighten Bleaching Gel 10% be measured for up to 6 months postinitiation Regardless, some dentists do not use even of treatment, and an observable change is 10% carbamide peroxide because they are con- required up to that time to gain product accep- cerned about the effects of the agents on the dental pulp. Very few clinical studies on the There are only five tooth whitening products reaction of the pulp to bleaching agents have accepted by the ADA as safe and effective.3 how 10% carbamide peroxide effects pulpal Daytime Professional Whitening System 10%a, tissues can now be answered with scientific Rembrandt® Lighten Bleaching Gel 10%b, Nite White® Classic Whitening Gel 10%c, Patterson In a study by Gonzalez-Ochoa,4 four bicus- Brand Tooth Whitening Gel 10%d, contrastP.M.® pid teeth that were going to be extracted for orthodontic reasons were bleached with an Whitening Gel 10%f. All of them use 10% car- bamide peroxide dispensed in trays. No product bleaching gel. One of the bicuspids was the con- with a greater than 10% carbamide peroxide con- trol tooth; one tooth was bleached overnight for centration that is used outside of the dental office 4 days; another tooth for 2 weeks; and another is accepted as safe and effective by the ADA.
for 2 weeks followed by 2 weeks of no bleaching.
All teeth were extracted at the same time. The aColgate Oral Pharmaceuticals, Inc, Canon, MA 02021; (800) 821-2880 Scandinavian Institute of Dental Research con- bDen-Mat Corp, Santa Maria, CA 9356; (800) 445-0345cDiscus Dental, Inc, Culver City, CA 90232; (800) 422-9448 ducted the evaluation of the pulp response.
dPatterson Dental, St. Paul, NM 55120; (800) 328-5536 There were no histological changes in any eSpectrum Dental, Inc, Culver City, CA 90232; (800) 556-7606fUltradent Products, Inck Sout Jordan, UT 84095; (800) 552-5512 of the sections from the control teeth. After 4 Compendium / April 2003
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Table 2—Tray-Used OTC Products With Their Assayed Concentrations
Carbamide Peroxide
Manufacturer
or Hydrogen Peroxide
Concentrations
aNatural White, Tonawanda, NY 14150; (800) 263-2290bDen-Mat Corp, Santa Maria, CA 93456; (800) 445-9448cSAS Group, Inc, Tarrytown, NY 01519; (914) 332-7878dUnilever, Greenwhich, CT 08630; (800) 778-5135eCCA Industries, Inc, East Rutherford, NJ 07073; (800) 524-2720 Figure 2—Objective evaluation of an overnight study using 10% and 15% carbamide peroxide, a daytime study using 5.5% hydrogen
peroxide and 15% carbamide peroxide, and another daytime study using 7.5% hydrogen peroxide and 20% carbamide peroxide.
days of exposure to the carbamide peroxide, bamide peroxide does not produce irreversible histological changes in the dental pulp.
mild reaction with 14 days of exposure to car- A study was conducted to determine if there was any difference in how fast teeth bleached reaction with 14 days of exposure followed by using 5%, 10%, and 16% concentrations of car- 14 days without the carbamide peroxide chal- bamide peroxide.5 One hundred and ten discol- lenge. None of the participants exhibited mod- ored teeth were divided into four groups. The erate or severe pulpal reactions as determined teeth were immersed for 8 hours in a different by histological changes to the pulp.
concentration of carbamide peroxide or saline in Pulp pathologists agree that mild histolog- an attempt to duplicate overnight use. The con- ical change is reversible. The conclusion of clusion states, “Lower concentrations of car- this study states that 10% carbamide peroxide bamide peroxide take longer to whiten teeth but may be considered to be safe for the dental eventually achieve the same result as higher con- pulp for a 2-week regimen of bleaching treat- centrations.”5 Therefore, 10% carbamide perox- ide may take a little longer, but will lighten to the assumed for 15% to 22% carbamide peroxide, level of the higher concentrations with time, and without irreversible changes to the dental pulp.
Compendium / April 2003
a large color change, 43% achieved a moderate color change, 7% a slight color change, and 3% did not experience any change. After 6 months, that rate dropped to 17%, 47%, 21%, and 14%, respectively. This was accomplished product where the subjects bleached overnight “Hollywood white” appearance at 4 weeks retained that for an extended period of time without rebleaching. This rate of color change, 0 4 6 12 16 20 24 28 32 36 40 44 48 52 56 60 64 68 72 76 80 84 88 92 96100104 however, will be different in young people who Figure 3—Two-year evaluation of tetracycline stained teeth using 10%, 15%, and
Verifying Actual Active Ingredient
20% carbamide peroxide in trays with reservoirs in a half-mouth study design. Concentration
teeth lighten to a certain level. In this regard, the phrase “inherent lightness potential” is School of Dentistry (IUSD) requested that all introduced. It is this author’s assertion that all teeth have an inherent lightness potential; whitening gels forward a sample of their vari- however, one patient’s teeth will lighten more ous concentrations to them. The over-the- than another patient’s teeth. Therefore, den- tists should not expect to lighten the teeth of whitening were purchased and tested for con- all their patients to the same degree.
centrations of carbamide peroxide or hydrogenperoxide (Sorhus J, Matis A. Degradation ofhydrogen peroxide and carbamide peroxidebleaching agents in vitro [unpublished study]) The science of tooth whitening is
still in its infancy, and many
using the US Pharmacopeia method.7 Testingwas done in triplicate (Tables 1 and 2). All questions and concerns remain. As
products were tested within the labeled use- more information about tooth
life, except the OTC products, which have no bleaching becomes available, it either
labeled use-life or labeled concentration.
By testing the dentist-prescribed gels, it strengthens existing concepts or
was found that one manufacturer’s products allows us to make appropriate modi-
were a mean 2.64% lower than what was post- fications to conform to new findings.
ed on the label, while another manufacturer’sproducts were a mean 0.91% higher than what Specifically, dental professionals must be careful not to promise results. Those who do tested, it was determined that one of the gels will certainly be disappointed: even manufac- turers admit that a very small percentage of trays was 0.7% hydrogen peroxide, the same patients will not experience a color change concentration as the manufacturer’s dentifrice.
with tooth bleaching. Teeth with yellow stains It is important for dentists to know the initial usually bleach better than teeth with gray actual concentration of products they are rec- stains. One study6 found that immediately after bleaching teeth, which were relatively dark(A3 Vita®,g shade or B56 in Trubyte® Appropriate Duration of Bleaching
Bioform®,h)in older adults, approximately 43% obtained a “Hollywood white” appearance, or concentration of carbamide peroxide was used inone group during the daytime and another group gVita Zahnfabrik, Germany, distributed in US by Vident, Brea, CA overnight.8 Both groups used the same 10% car- hDENTSPLY, York, PA 17405-0872; (800) 877-0020 bamide peroxide agent in trays with reservoirs.
Compendium / April 2003
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Figure 4—At baseline, a 27-year-old female with tetracycline-
Figure 5—At one month after maxillary teeth were bleached
overnight using trays with 20% carbamide on right side, and10% carbamide peroxide on left side. Figure 6—Results at 3 months.
Figure 7—Results at 6 months; bleaching was discontinued.
Figure 8—At 9 months, 3 months postbleaching.
Figure 9—At 2 years, 18 months, postbleaching. Patient was
given bleaching gel for mandibular teeth after a 9-month bleach-
ing evaluation.
One group bleached for 7 overnight periods of The subjective evaluation using the shade time and the other group for 14 two-hour day- guide demonstrated that the higher the con- time periods. The value change, or L* change, centration and the longer the tray is worn, the was not significantly different for the 10% car- faster the lightening of the teeth would occur bamide peroxide overnight for the 7-days group (Figure 1).11-13 The 10% overnight carbamide than the 2 hours-a-day for 14 days group. peroxide agent had the same delta shade guide Three studies have been conducted at IUSD values as the 20% carbamide peroxide product and reported in the scientific literature that help used twice a day for 14 days. The 15% car- clarify the factors of gel concentration and use bamide peroxide product that was used for time.9-11 Each had more than 24 subjects, used only half an hour twice a day demonstrated a trays with reservoirs, and followed the half- mouth study design. All of the patients bleached Therefore, bleaching was shown to be time for 14 days and were evaluated not only subjec- tively, using a shade guideh, but also objectively The objective evaluation using a colorime- using a colorimeter (Chroma Meterci CR-321).
ter with a positioning jig showed that the Delta Compendium / April 2003
CE 3 E value, at the end of 6 weeks, was the same for inhibit its ability to lighten the teeth if the gel
was intended to be left on for a longer period peroxide concentrations (Figure 2).11-13 The of time. The ingestion of the additional oxi- color of teeth could be pushed, but a higher dant is also a factor for concern. While it is not concentration will rebound more rapidly. The known how much oxidant is safe to ingest, one tooth never reached its inherent lightness study reported that amount to be 10 mg, with potential, in the study comparing 5.3% hydro- a safety factor of 100.15 The amount ingested gen peroxide and 15% carbamide peroxide, so should be minimixed until more scientific evi- there was a minimal rebound of the color. dence of the ability of anti-oxidants available in the oral cavity to overcome the increased oxidant level that results from bleaching can twice a day was the same as a 10% carbamide peroxide concentration used overnight whenboth were used for 14 days. However, the 20% Efficacy of Tray Bleaching Compared to
carbamide peroxide is not accepted by the In-Office Bleaching
ADA as safe and effective, and dentists may A split-mouth design study was completed16 feel more confident that they are providing in which 2 in-office treatments and 2 weeks patients with the best service by recommend- of bleaching in trays with reservoirs were conducted on 24 subjects. Two ADA accept- ed tooth-whitening agents, one for in-officeuse and the other for at-home use, were com- Usefulness of Reservoirs
pared side-by-side for color changes, both One of the existing controversies regard- subjectively and objectively. Objectively, at ing tray bleaching involves the use of reser- voirs. A study involving 27 subjects was con- change or E value of the teeth bleached with ducted with a split-mouth design in which reservoirs were placed on only one side of the twice the value compared to the side that was tray and no reservoirs were placed on the other bleached using the in-office tooth whitening side.12 A 16% carbamide peroxide gel was used agent. The subjective values indicated that in their trays for 2 hours once a day. At the end the at-home side was about one-third lighter of 14 days, there was a statistical difference in the objective measurement of Delta E, which patients sometimes request in-office treat- continued until the end of the study. However, ment, when providing this service, the rec- there was no difference in the subjective mea- ommendation should be to follow it up with surement of lightening using a shade guide, because visual acuity is unable to differentiateless than one Delta E value.13 Therefore, from Efficacy of Tray Bleaching Against
a clinical standpoint, placing a reservoir in Stubborn Stains
Another study analyzed the amount of car- reported results for 59 subjects in a half- bamide peroxide recovered after 2 hours of use mouth design study.17 The subjects used 10% in 2 products without reservoirs, and one prod- vs 15% vs 20% carbamide peroxide on differ- uct with reservoirs.14 Approximately the same ent sides of the maxillary arches, overnight, amount of agent was placed into trays with and in trays with reservoirs, for 6 months. The without reservoirs. The investigators were able subjects also recorded the maximum amount to recover twice as much of the initially placed of sensitivity they experienced each day on agent in the trays that had reservoirs compared their right and left sides (Figure 3).
to the trays that did not have reservoirs. In nine trials, no active agent could be assayed the shade guide values in the 10%, 15%, and from one of the products that recommended 20% carbamide peroxide groups after 2 years.
Twenty percent and 15% carbamide peroxide The lost gel exuded from the tray without caused significantly more tissue sensitivity reservoirs was probably ingested, which would than 10% carbamide peroxide. There was no Compendium / April 2003
significant difference in tooth sensitivity.
International, Life-Like Cosmetic Solutions, Subjects reported being happy to be able to CE 3
lighten their teeth with the use of trays withall of the concentrations. Therefore, when References
each option is effective, but it takes a little Matis BA. Degradation of gel in tray whitening.
longer to do it safely, it is this author’s asser- Compend Contin Educ Dent. 2000;21(suppl 28):S28-S-35.
ADA Council on Scientific Affairs: Home-use tooth tion that the safe way should be more seri- whitening products. ADA Publishing, Chicago, IL: May, American Dental Association Website. The ADA Sealof Acceptance. Consumer Products: By Category.
Available at: http://www.ada.org/prof/prac/seal/cons/tc- stains. All of the products in this category Gonzalez-Ochoa J. Histological Changes to Dental Pulpafter Vital Bleaching with 10% Carbamide Peroxide [masters appear to be effective, whether 5% to 22% thesis]. Indiana University School of Dentistry, carbamide peroxide or 3% to 9.5% hydrogen peroxide. However, 10% carbamide peroxide Leonard RH JR, Sharma A, Haywood VB. Use of differ- has been accepted as safe by the ADA, while ent concentrations of Carbamide Peroxide for bleachingteeth: An in vitro study. Quintessence Int. 1998;29:503- higher concentrations have not. It is also important for dentists dispensing gel for tray Matis BA, Cochran MA, Eckert G, et al. The efficacy use to know the actual concentrations of the and safety of a 10% carbamide peroxide bleaching gel.
Quintessence Int. 1998;29:555-563.
products they prescribe. With overnight use, The United States Pharmacopeia. Carbamide Peroxide.
patients will achieve the greatest benefit United States Pharmacopeia. 2000;24:301-302. 26th ed.
from the gel and require a shorter number of Poore CL, Maddux AM, Cristante MM, et al.
bleaching days, although manufacturer’s Comparison of two tooth bleaching regimens using 10% instructions should be followed. There will Carbamide Peroxide. J Dent Res. 1998;78(special be no difference in how rapidly bleaching occurs in the daytime regardless of whether Matis BA, Mousa HN, Cochran MA, et al. Clinical eval-uation of bleaching agents of different concentrations.
reservoirs are used, but patients will swallow Quintessence Int. 2000;31:303-310.
less of the product if reservoirs are used. If in- Panich M. In vivo evaluation of 15% Carbamide Peroxide office bleaching is performed, it should be and 5.5 Hydrogen Peroxide Whitening Agents DuringDaytime Use [masters thesis]. Indiana University School of Dentistry, Indianapolis, Indiana, 1999. Mokhlis GR, Matis BA, Cochran MA, et al. A clinical evaluation of carbamide peroxide and hydrogen peroxidewhitening agents during daytime use. J Am Dent Assoc.
agent may require more time, but doing so may bring the peace of mind that comes with Matis BA, Hamdan YS, Cochran MA, et al: A clinical using an ADA-accepted product. If problems evaluation of a bleaching agent used with and without arise—and there has already been litigation reservoirs. Oper Dent. 2002;27:5-11.
Ruyter IE, Niler K, Moller B. Color stability of dental composite resin materials for crown and bridge veneers.
10% carbamide peroxide—and the manufac- turer’s directions have been followed, the Matis BA, Yousef M, Cochran MA, et al. Degradation ofbleaching gels in vivo as a function of tray design and ADA will stand by you and defend your use Carbamide Peroxide concentration. Oper Dent.
of the ADA-accepted product, if it becomes necessary. For this author, peace of mind and Dahl JE, Becher R. Acute toxicity of carbamide peroxideand a commercially available tooth-bleaching agent in patient protection is of primary importance.
rats. J Dent Res. 1995;74;710-714.
Zekonis R, Matis BA, Cochran MA, et al: Clinical eval- Disclosure
uation of in-office and at-home bleaching treatments.
Matis BA, Wang Y, Jiang T, et al. Extended at-home bleaching of tetracycline-stained teeth with different Products, Inc, Discus Dental, Inc, Den-Mat concentrations of carbamide peroxide Quintessence Int.
Compendium / April 2003

Source: http://www.oralway.com.br/arq_heraldo/Matis,%202003.pdf