Clinical Evaluation of Chemical and Light-Activated Tooth Whitening Lights

The Journal of Contemporary Dental Practice

Abstract: Tooth whitening has become one of the most popular cosmetic treatments available. This article compares the efficacy of 4 in-office whitening system lights using a split-arch, randomized, parallel, blinded clinical evaluation study. Both in-office tooth whitening lights were effective and there was no significant statistical difference over the period of observation.

Twenty patients participated in the study. The bleaching gels were all 14 percent H2O2. The 4 lights that are being evaluated is the Brite XL3, the Crystal 1400, the IBrite, and the Zoom2. Patients’ mouths were divided into quadrants with the upper right quadrant using the Brite XL3, the lower right using the I-Brite, the upper left using the Aladdin Wireless Light, and the lower left using Beyond Dental Light. After the treatments were complete, all quadrants brightened equally on 90 percent of the patients studied.

Conclusion: There is no significant difference in the whitening power of the LED lights. All lights brightened equally well.

In 2006 and 2007, several articles were published that evaluated the efficacy of light-activated bleaching lights. One study reported positive results,3 whereas the other articles concluded the opposite.4,5 It is apparent that the dental profession needs more evidence to provide for better and more efficient treatment. The need for more knowledge becomes even more important as manufacturers inundate the dental profession with advertisements promoting light-activated tooth whitening as "state of the art" and propose that it is an integral component of the modern dental office.

Background. The authors tested the adjunctive use of light with a 15 percent peroxide gel as a single-visit, in-office tooth whitening system.

Read the full article HERE

Blue light fights gum disease culprits, Forsyth scientists find

Main Category: Dentistry News
Article Date: 01 Apr 2005 - 0:00 PDT

Boston--Scientists at The Forsyth Institute have found that blue light can be used to selectively suppress certain bacteria commonly associated with destructive gum disease.

The research, published in the April Journal of Antimicrobial Agents and Chemotherapy, suggests that light in the blue region of the visible spectrum might be useful in preventing, controlling or treating periodontitis -- an oral infection that can lead to loss of bone and teeth.

"Some of the key bacterial pathogens associated with periodontitis produce and accumulate compounds that are sensitive to light," said Nikos Soukos, DDS PhD, Director of the Forsyth Laboratory of Applied Molecular Photomedicine and the principal investigator. "We found that, when exposed to particular wavelengths of light, a percentage of those pathogens was eradicated within seconds."

Another important finding was that when the proportion of such pathogens was reduced, the proportion of other, potentially helpful, bacteria increased. "This suggests that it might one day be feasible to use light to restore a healthy bacterial balance in the mouth," Soukos said.

The current research stemmed from an observation by Max Goodson DDS, PhD, Director of Clinical Research at Forsyth, that the blue light used in a tooth whitening procedure appeared to decrease inflammation of the gums.

The team is currently developing a hand-held, light-based device that might, one day, be used by consumers to help combat periodontal disease.

If proved effective in clinical trials Goodson said, "Technology employing blue light to improve oral ecology could be the most important advance in maintaining periodontal health since the invention of the toothbrush."

Background
Previous Forsyth research had shown that as many as 700 different types of oral bacteria may be found in dental plaque that accumulates on teeth. While some bacteria appear to be benign or even helpful, others may invade and destroy gum tissue and bone -- leading to loss of teeth, and, possibly, to infection elsewhere in the body.

Among the more destructive bacteria are the so-called "black-pigmented bacteria" (BPB) which have been implicated as pathogens associated with periodontitis. Such bacteria accumulate black pigment consisting mainly of organic compounds called porphyrins. Some porphyrins are photosensitive, and, when activated by visible light, induce a photodynamic reaction that kills the microorganism within seconds.

In embarking on their research, Soukos and Goodson knew that other researchers had used lasers to deliver red or green light, which partially inactivated certain oral bacteria. The Forsyth team also knew, from published reports, that porphyrins absorb blue light more readily than light that is red or green.

The team employed a halogen lamp source commonly used for tooth whitening to shine broadband light comprised mainly of blue and a small percentage of green light (wavelengths ranged from 380 to 520 nanometers) on pure cultures of BPB and on dental plaque samples obtained from individuals with chronic periodontitis.

They found that the light rapidly killed BPB in pure cultures and that it selectively eliminated BPB in plaque samples containing 500-600 different bacteria. They also found that certain species were more readily inactivated by the light than others and that varying the intensity and exposure time had different impacts on different species.

The researchers conclude that intraoral light exposure can selectively reduce pathogens in dental plaque.

If proved effective in clinical studies, the findings could lead to new methods for preventing or controlling periodontal disease. Such methods would be rapid, non-invasive, and nontoxic, Soukos said.

1 Hour Light Activated Teeth Whitening Comparing 16% Hydrogen Peroxide Gel with 44% Carbamide Peroxide Gel.

Background. Vital tooth bleaching for esthetic reasons has significantly gained in popularity during the last few years. However, few studies have investigated the efficacy of daytime or 1-hour bleaching products with use of a bleaching light as a catalyst.. For the purposes of the test, the Light was not part of the evaluation, only utilized as the standard by which the procedure is performed throughout various offices. The purpose of this double-blind in vivo study was to evaluate the efficacy of 44 percent carbamide peroxide, or CP, and 16 percent hydrogen peroxide, or HP, during daytime use, and less than 1-hour utilizing a standard LED light operating in the broad spectrum of 470-510 Nanometers. The degree of color change, any color relapse, and tooth or gingival sensitivity were evaluated. Results.

Materials and Methods:

• six maxillary anterior teeth present and free of any restorative material covering more than one-sixth of their labial surfaces;

• six anterior teeth darker than B-54 and lighter than B-85 on the Trubyte Bioform Color Ordered Shade Guide (Dentsply Trubyte);

• at least 18 years of age, willing to sign a consent form, able to return for periodic examinations, and willing to refrain from use of tobacco products during the study period.

Potential subjects were excluded on the basis of:

• pregnant or lactating women.

• a medical condition that might interfere with the study results or require special attention;

• a gingival index score greater than 1.0 or gross pathology in the mouth;

• tetracycline-stained teeth or having undergone endodontic therapy in any of the maxillary anterior teeth;

• use of professionally applied tooth whiteners within the past five years;

• use of any kind of tobacco products during the past 30 days;

Twenty-four patients volunteered to participate in this double-blind study, for which they received $100. The study protocol was reviewed and approved by the Institutional Review Board of Indiana University Purdue University Indianapolis. Patients received a dental screening and prophylaxis by a licensed hygienist or dentist at least two weeks before the study. All 24 subjects met the following criteria:

• Use of the 16 percent HP resulted in significantly more lightness than the 44 percent HP after the 1-hour treatment.

• Patients teeth with the placement of the 16 percent HP improved p < 0.0001 or a mean of 5 shades B* whereas there was little or no difference in the color using the 44 percent HP.

• After 2-hours of use utilizing the 44 percent CP, there was a color mean of 1 shade B*, and produced sensitivity in 25% of the patients.