Daily Use of Whitening Strips on Tetracycline- Stained Teeth: Comparative CE 4 Results After 2 Months Gerard Kugel, DMD, MS Professor Dean for Research Abstract: This article reviews the efficacy of a new 6.5% hydrogen peroxide tooth-whitening gel strip for bleaching teeth that have been intrinsically stained Ayman Aboushala, DDS, MS from tetracycline. Given the severity of staining in the cases presented during a recently conducted clinical trial, the resulting efficacy is dramatic. Additionally, Tufts University School of Dental Medicinethe continuous use of these strips for 30 minutes per day, twice daily for 2 months with no meaningful adverse effects is noteworthy. Xiaojie Zhou, PhD
In cases requiring esthetic enhancement of discolored dentition, those involv- Statistician
ing tetracycline stains are among the most challenging. These intrinsic stains,
Robert W. Gerlach, DDS, MPH
which cannot be removed with polishing or abrasive mechanisms, may result
from the administration of tetracycline during childhood for the treatment of
disease. The color and severity of stains vary and are influenced by the duration
of tetracycline use, and the stage of tooth development at the time the medica-tion was prescribed.
While some patients may select veneers or full-coverage crown restorations
to brighten their smiles, others may desire a more conservative approach. To thatend, tooth whitening offers a simplified and economical alternative for changing
Learning Objectives
When clinicians are faced with the prospect of whitening a patient’s intrin-
sically stained teeth, considerations for treatment include the shade and location
of discoloration,1 as well as which formulation of whitening solutions to use.
Whether whitening should take place in the office or at home under the den-
tist’s supervision, along with the longevity of the whitening protocol, must also
be decided. It has been suggested that when discoloration appears at the cervical
area of the tooth, the whitening results may be poorest; when the stain is dark
gray or blue, the prognosis is similarly unimpressive. When whitening tetracy-
cline-stained teeth, patients may need to commit to a course of treatment last-
Treatment commonly involves the use of at-home vital bleaching kits, which
polyethylene film whiten-ing system with a tray
were first introduced in 1989.5 According to some reports, tetracycline-stained teeth
have demonstrated a favorable prognosis depending on the treatment protocol,although they are the most resistant to bleaching.6 Specifically, one report showedthat 97% of patients with tetracycline stains experienced successful tooth lighten-ing when a carbamide peroxide whitening solution was used in a nightguard.2
A recently introduced 6.5% hydrogen peroxide whitening delivery system
(Crest® Professional Whitestripsa) shows promise for whitening tetracycline-stained dentition when used at home for 2 months under a dentist’s supervision. The hydrogen peroxide–coated polyethylene strips represent an alternative forpatients who cannot afford other whitening treatments and/or do not have timefor multiple dental visits.7 This article presents the recent research findings of aclinical trial designed to evaluate the efficacy of two at-home vital bleaching sys-tems on tetracycline-stained teeth.
a The Procter & Gamble Co, Cincinnati, OH 45202; 800-492-7378
Compendium / Special Issue
products were packaged in 1-month product
CE 4
kits, and all labeling was identical except for a
efficacy of two at-home vital bleaching sys-
unique subject identification number.
tems on tetracycline-stained teeth. Daily
bleaching was conducted for 2 months.
vised for instructional purposes, but all other
Eligibility was limited to healthy adult volun-
treatment was unsupervised. Only the maxil-
lary arch was treated. Participants in the strip
including at least 3 gradable maxillary incisors
group were instructed to wear a whitening
with significant tetracycline staining. In-
strip for 30 minutes twice daily. Individuals in
dividuals demonstrating tooth sensitivity or
the tray group had a custom soft, full-arch
an immediate need for dental treatment were
bleaching tray fabricated with gingival scal-
excluded from participating in this trial.
loping and gel reservoirs using materials sup-plied by the manufacturer. Subjects in thatgroup were instructed to place half to threequarters of the contents of a bleaching syringeinto the custom tray and wear the device for
In cases requiring esthetic enhancement of discolored dentition, those involving tetracycline stains are among
beginning of the study and again each monthafter treatment. First, the level of tetracycline
the most challenging.
staining on the maxillary anterior teeth wasassessed using a modified standard index.8
This modification recognized the possibility of
and advertising were reviewed and approved
successfully bleaching teeth with relatively
by Tuft University’s Institutional Review
severe tetracycline stain (Table 1). These
Board. Written and verbal informed consent
baseline values, along with age, were used for
was received before study initiation. After
balance and assignment during treatment ran-
informed consent was obtained and baseline
domization. Efficacy was assessed using a stan-
measurements were made, subjects were dard 16-step value-oriented tooth shade guidecrandomized 3:1 to a strip-based, hydrogen
to match artificial crowns to the natural den-
peroxide tooth-whitening system (Crest® Pro-
tition. Shade assessments were made in a neu-
fessional Whitestrips) or a marketed tray-
tral-colored dental operatory under color-bal-
based, carbamide peroxide whitening system
anced lighting conditions by a trained and
calibrated examiner. Tolerability was assessed
by intraoral examination and subject report at
frice (Crest® Cavity Protection Regular Pastea)
and an extrasoft toothbrush (Crest® Com-
pletea) for use throughout the study. All test
by ranking the 16 shade tabsc, arranged from
b Ultradent Products, Inc, South Jordan, UT 84095; 800-552-5512
dark to light, according to the rank order sug-gested by the manufacturer. To account forunusually dark colors (often seen with tetracy-cline staining) or white colors (often seen
Table 1—Tetracycline Stain Classification*
postbleaching), this 16-step guide was supple-
Clinical Presentation
mented by 2 additional values (C4+ and B1–)
representing shades darker than C4 or lighter
Uniform light yellow, brown, or gray stain confined to
than B1. Effectiveness was determined by cal-
culating the change in shade scores from base-line at each posttreatment visit. Using this
Deep yellow, brown, or gray stain, without banding
method, a decrease in numeric shade score
Dark gray or blue stain with marked banding
represented an increase in tooth whiteness.
Treatment groups were compared using analy-
c Vita Zahnfabrik, Germany; distributed in the US by Vident™, Brea, CA
Compendium / Special Issue
sis of covariance with the baseline shade as
the more severe banding that is occasionally
CE 4
the covariant. Comparisons to baseline were
reported after childhood antibiotic use. While
tobacco use was uncommon (15% of subjects),
were 2-sided using a 5% significance level.
95% of the study participants consumed cof-fee, tea, or cola beverages daily. Treatment
respect to demographic and behavioral param-
eters and tetracycline stain levels (Table 2).
assigned to the tray group. The study popula-
Both treatments were effective overall in
tion ranged from 22 to 70 years of age.
improving the shade of tetracycline-stained
Approximately half of the subjects presented
teeth (Table 3). Relative to baseline, the 2
with moderate-to-severe tetracycline staining
groups averaged approximately 4.1 to 6.6 units
(levels II through IV), a third of whom had
of shade improvement after 2 months of treat-
Table 2—Baseline Demographic, Behavioral, and Tooth Shade Information Demographic, Behavioral Two-sided Characteristic P-value Age (years) Tobacco Use Daily Coffee/Tea/ Cola Consumption Tetracycline Stain Levels Tooth Shade Compendium / Special Issue CE 4 Table 3—Tooth Shade by Treatment and Time Between-Group Comparison Comparison to Baseline Mean Treatment Mean Shade Change P-value Difference (SE) P-value Table 4—Tooth Sensitivity and Oral Irritation Strip (n = 30) Tray (n = 10) Overall (n = 40) Number of Number of Number of Subjects Subjects Subjects Subjects Subjects Subjects Reported Observed
clinical manifestations present at the 1-month
greater after 2 months than after 1 month.
or 2-month clinical examinations. Seven sub-
Response was faster in the strip group.
jects discontinued treatment during the first 2
During the first month of treatment, the strip
months (3 in the tray group and 4 in the strip
group averaged more than a 4-unit reduction
group). Of these, 2 individuals in the tray
in tooth shade, which represented a statisti-
group reported the regimen was inconvenient
cally significant (P < 0.0001) improvement vs
and withdrew after the 1-month visit. The
baseline. In contrast, the tray group averaged
remaining patients withdrew because of an
less than a 1-shade reduction during the first
inability to make the scheduled recall appoint-
month, not differing statistically from baseline
(P > 0.10). Adjusting for baseline, the strip
modifying their treatment regimen because of
group averaged 2.6 to 3.2 units greater shade
reduction than the tray-group control. Withrespect to between-group comparisons, thestrip group experienced statistically significantsuperior reductions (P < 0.01) in shade com-
The strip group averaged
pared with the tray group at both the 1- and 2-
2.6 to 3.2 units greater shade reduction than the tray-
Both treatments were generally well toler-
group control.
ated. Mild and transient tooth sensitivity andoral irritation were the most common adverseevents associated with daily bleaching (Table
Discussion
4). These events typically were reported early
This study was designed to evaluate clin-
in the treatment regimen, and there were no
ical response after longer-term, daily use of
Compendium / Special Issue CE 4 Figure 1A—Pretreatment tooth color. Figure 1B—After 2 months of daily bleach- Figure 1C—After 2 months of daily bleach- ing with whitening strips compared with Figure 2A—Pretreatment tooth color. Figure 2B—After 2 months of daily bleach- Figure 2C—After 2 months of daily bleach- ing with whitening strips compared with
6.5% hydrogen peroxide whitening strips.
greater shade improvement overall compared
to the tray control group. While overnight
treatment in individuals with tetracycline
tray use may improve clinical response in that
staining because this clinical condition is
group, such daily treatment conducted over
reported to require extended treatment of
the long term could also affect subject com-
ingful whitening.9 A marketed 10% car-bamide peroxide, tray-based system wasselected as the control group because thisagent has been used previously and reported
The use of whitening strips has
to be effective in longer-term studies of tetra-
been proposed as a viable
cycline staining.10,11 Other concentrations
option for longer-term whitening because of favorable compliance,
tems were effective, with both groups differ-
lower systemic exposure, and other
ing significantly from baseline at the end of
factors associated with this easy- to-use bleaching system.
response in the strip group was superior to thetray group, as evidenced by the significant (P< 0.01) between-group treatment differences,
favoring the “trayless” whitening strip system,
was impressive (Figures 1A through 2C).
at both 1 and 2 months. Onset of these clini-
However, this study confirms early observa-
cal benefits was more rapid in the strip group.
tions that extended contact time is needed in
After 1 month of treatment, the strip group
months of daily treatment, involving approxi-
than 4 shades compared to less than 1 shade
mately 60 hours of strip use or 120 hours of tray
in the tray group. Also, only the strip group
use, no subjects had yet reached the predeter-
experienced statistically significant improve-
mined bleaching cutoff, B1. Additional treat-
ments in tooth color after 1 month. After 2
ment time may be necessary in these subjects
Compendium / Special Issue Disclosure CE 4 treatment, hence the time point elected for
The research was supported by The Procter
this study.12 The researchers expect to contin-
ue treatment and observation of this studypopulation for up to 6 months to further assess
References
the effectiveness and tolerability of these
Haywood VB, Leonard RH, Nelson CF, et al: Effectiveness,side effects and long-term status of nightguard vital bleach-
ing. J Am Dent Assoc 125(9):1219-1226, 1994.
Twice-daily use of the 6.5% hydrogen per-
Haywood VB, Leonard RH, Dickinson GL: Efficacy of six
oxide whitening strips was well tolerated over
months of nightguard vital bleaching of tetracycline-stained
the 2-month treatment period. The side effects
teeth. J Esthet Dent 9(1):13-19, 1997.
Haywood VB: Extended bleaching of tetracycline-stained
in this study—transient tooth sensitivity and
teeth. Contemp Esthet Rest Prac 1(1):14-21, 1997.
gingival irritation—generally were similar in
Haywood VB: Bleaching tetracycline-stained teeth. Esthet
nature and severity to the primary events
Haywood VB, Heymann HO: Nightguard vital bleaching.
reported in other longitudinal trials using the
Quintessence Int 20(3):173-176, 1989.
at-home tray-bleaching systems.9 In the cur-
Haywood VB, Leonard RH, Nelson CF: Efficacy of 6-
rent study, where the whitening strips were
months’ nightguard vital bleaching of tetracycline-stainedteeth [abstract #2358]. J Dent Res 73, 1994.
used for a total of 60 contact hours over a 2-
Kugel G: Nontray whitening. Compend Contin Educ Dent
month period, no subject in the strip group dis-
continued treatment because of an adverse
Boksman L, Jordan RE: Conservative treatment of thestained dentition: vital bleaching. Aust Dent J 28(2):67-72,
event. This extended exposure associated with
long-term, daily treatment of tetracycline stain
Leonard RH: Nightguard vital bleaching: dark stains and
corroborates and extends the safety of strip-
long-term results. Compend Contin Educ Dent 21(suppl
based tooth whitening as reported in earlier,
Leonard RH, Haywood VB, Eagle JC, et al: Nightguard vital
bleaching of tetracycline-stained teeth: 54 months post treat-ment. J Esthet Dent 11(5):265-277, 1999. Conclusion
Matis BA, Wang Y, Jiang T, et al: Six-month evaluation ofbleaching agents in patients with tetracycline staining
The use of whitening strips has been pro-
[abstract #1175]. J Dent Res 80:182, 2001.
Haywood VB: Current status of nightguard vital bleaching.
whitening because of favorable compliance,
Compend Contin Educ Dent 21(suppl 28):S10-S17, 2000.
Gerlach RW: Shifting paradigms in whitening: introduction
lower systemic exposure, and other factors
of a novel system for vital tooth bleaching. Compend Contin
associated with this easy-to-use bleaching sys-
Educ Dent 21(suppl 29):S4-S9, 2000.
tem.14 New clinical research involving extend-
Kugel G, Kastali S: Tooth whitening efficacy and safety: arandomized and controlled clinical trial. Compend Contin
ed treatment of tetracycline stain for 2 months
Educ Dent 21(suppl 29):S16-S21, 2000.
confirms this proposition. In the current study,
Gerlach RW, Jeffers MJ, Pernik PS, et al: Impact of prior
tooth brushing on whitening strip clinical response [abstract
hydrogen peroxide whitening strip provided
#922]. J Dent Res 80:151, 2001.
Gerlach RW, Campolongo KL, Hoke PD, et al: Use of per-
efficacy similar to 2 months of treatment with
oxide-containing polyethylene strips: effect of dosing dura-
a 10% carbamide peroxide tray system.
tion on initial and sustained shade change [abstract #920]. J Dent Res 80:150, 2001.
Gerlach RW, Gibb RD, Sagel PA: A randomized clinical trial
Acknowledgments
comparing a novel 5.3% hydrogen peroxide whitening strip
to 10%, 15%, and 20% carbamide peroxide tray-based
tions of Lisa Bowman, AS, Senior Researcher,
bleaching systems. Compend Contin Educ Dent 21(suppl29):S22-S28, 2000.
Clinical Data Management; Donna McMillan,
McMillan DA, Gibb RD, Gerlach RW: Impact of increasing
PhD, Principal Scientist, Toxicology; Sarah
hydrogen peroxide concentration on bleaching strip efficacy
Towers, Research Administrator; and Patricia
and tolerability [abstract #1102]. J Dent Res 80:173, 2001.
Swift EJ, Heymann HO, Ritter AV, et al: Clinical evaluation
of a novel “trayless” tooth whitening system [abstract #921].
Clinical Trials Management, to this research. Compendium / Special Issue
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HE CALLER SAYS THAT SHE IS BEING ATTACKED by invisible mites. The attack has been going on for Tmonths and she has visited a half dozen physicians, but none was able to help her. Two prescribed Kwell lotion (see Glossary), but the sensations persist. She has treated her skin with alcohol, vinegar, Lysol, bleach, kerosene, and various home remedies. She has boiled her bed linens and clothing da