Whitening Treatment Research Articles

A Photoplethysmography Melanin Evaluation System by Modified Boltzmann Transport Equation (BTE)

With the advance in cosmetic medical technology in recent years, more and more people get cosmetic medical treatments, especially skin whitening treatments. Nevertheless, people usually assess the effect of skin whitening products by vision, which is subjective and will be different from each person. To acquire the value of melanin concentration objectively, people need to go to cosmetic medical clinics. This will cause inconvenience to people. This paper develops a novel evaluation platform based on optical assessment methods, which employ different absorption and scattering properties to different wavelengths of light in human tissue to obtain melanin concentration. Moreover, this paper proposes a new method that compensates the interaction between epidermis and dermis to acquire the melanin concentration more accurately. The novel platform designed in this paper is smaller and consumes lower-power and smaller when comparing to other conventional devices in market.

VİTAL DİŞLERDE BEYAZLATMA

Today, tooth whitening treatment has gained importance with increasing aesthetic expectations. Tooth discoloration can cause aesthetic problems; as a result, can lead to psychological and social problems. Whitening treatment removes effectively teeth discoloration. Agents of various concentrations in teeth whitening treatment are used with different techniques. Bleaching can be applied both at home and at the office with carbamide peroxide or hydrogen peroxide. Over-the-counter products (OTC) applied in a similar vay to home bleaching techniques are also available. Bleaching treatment have been accepted by the public as a more conservative and economical method of improving the aesthetic appearance of the teeth. Vital tooth bleaching applications are discussed in this article. Key Hydrogen peroxide words: Bleaching, Discoloration

Influence of Fluorescence Whitening Treatment on the UV Blocking Property of 100% Cotton Knitted Fabric

This paper was concerned with the effect of fluorescence whitening treatment on the UV blocking effect of 100% cotton knitted structure. UV measurement was carried out using a spectrophotometer and UVA transmission and UPF were obtained. The results revealed that fluorescence whitening process did affect much the UV blocking effect.

A new three-component formulation for the efficient whitening of teeth (Carbamide Plus).

This study aimed to develop and characterise a new three-component dental whitening formulation which is as effective as the currently used carbamide peroxide but at significantly lower hydrogen peroxide concentrations. The new formulation (Carbamide Plus) was prepared containing hydrogen peroxide, urea, and sodium tripolyphosphate and compared directly with carbamide peroxide (containing just hydrogen peroxide and urea). To evaluate the clinical effectiveness of 5% Carbamide Plus, a randomised double-blind placebo-controlled clinical trial was conducted comparing the tooth colour of 33 patients using L*a*b* scores at baseline and after a 2-week whitening treatment. The behaviour of the three components in solution was determined by (1)H and (31)P NMR spectroscopy and pH dilution experiments. This clinical trial revealed that 5% whitening gels containing Carbamide Plus were as effective as those containing 10% carbamide peroxide. (1)H and (31)P NMR spectroscopy revealed strong intermolecular interactions between hydrogen peroxide and both urea and sodium tripolyphosphate (STPP) with little apparent interaction between urea and STPP. In this manuscript, we postulate that this increased whitening efficiency is due to a marked increase in local pH upon dilution which destabilises the hydrogen peroxide and expedites the whitening process. We postulate Carbamide Plus to be a three-component adduct with two molecules of carbamide peroxide binding to a central STPP unit with no direct interaction between STPP and urea. There were no statistically significant differences between Carbamide Plus and 10% carbamide peroxide in tooth-whitening achieved at 2 weeks. These results were recorded following 2 weeks of 2-h daily wear of at-home trays. Carbamide Plus offers the potential of using significantly lower levels of hydrogen peroxide concentration to achieve similar dental whitening effects.

Critical appraisal. In-office tooth whitening: pulpal effects and tooth sensitivity issues.

In-office bleaching is an effective method for whitening teeth.Tooth sensitivity associated with in-office whitening is reversible and may range from mild to considerable. The incidence and severity of tooth sensitivity can be reduced by pretreatment with a desensitizer such as potassium nitrate. Histologic studies and clinical studies on long-term pulpal effects are lacking to definitively support the safety of in-office tooth whitening. Future studies on the etiology of tooth sensitivity related to whitening might greatly improve the means of preventing and managing this side effect.

Treatment Responses to Tooth Whitening in Twins

The aim of this study was to determine heritability estimates of treatment responses to a 10% hydrogen peroxide strip-based whitening system in twins. Eighty-five twin pairs were randomly assigned to 10% hydrogen peroxide whitening strips or placebo strips without peroxide. Both twins (monozygotic or dizygotic) received the same treatment. Maxillary teeth were treated for 30 minutes twice daily for 7 days. Efficacy was measured objectively as L* (light-dark), a* (red-green), and b* (yellow-blue) color change from digital images at baseline (∆) and day 8. Heritability estimates for tooth whitening treatment responses for changes from day 8 to baseline were obtained using variance-component methodologies. Whitening treatment responses were highly heritable (h(2) = 71.0) for ∆b* and ∆a*(p < .0001), but not for ∆L* (h(2) = 27.0), which was essentially modulated by environmental factors. This study has demonstrated that both genetic and environmental factors significantly contributed to seven-day whitening treatment responses achieved with 10% hydrogen peroxide strips.

The bleaching efficiency of KTP and diode 810 nm lasers on teeth stained with different substances: An in vitro study.

The purpose of this study was to evaluate the bleaching efficiency of two different lasers (KTP and diode 810 nm) on teeth, randomly divided by means an Excel function (Microsoft Excel 2010 "Fx causale") and stored in physiological solution, that were previously stained with different substances commonly considered as a cause of tooth discoloration, such as coffee, tea and red fruits and to investigate the role of laser irradiation in an experimental model, during the dental bleaching process. Three groups of 45 bovine teeth were created and immersed for one week in a solution of tea, coffee or red fruits respectively. Each group was divided into three sub-groups of fifteen teeth. One was bleached with a 30% hydrogen peroxide gel for 30 min only as control, another 15 teeth group was bleached with the gel plus 810 nm diode laser irradiation and the last group was bleached with the gel plus KTP irradiation. The lasers were applied in three cycles of 30 sec each with a power of 1.5 W localized on a 10 mm spot on the teeth. The temperature of the gel was checked during the bleaching procedure using a thermometer and the colour of each tooth was measured by a spectrophotometer. Statistical analysis of the collected data was performed using Graph Pad Prism, version 6.01 software, Kruskal-Wallis test and Dunn's multiple comparison test and Mann-Whitney test. P value <0.0001 was considered extremely significant (***), P value between 0.001 to 0.01 very significant (**), P value between 0.01 to 0.05 significant (*) and P value >0.05 not significant (ns). By these tests diode laser was effective only at bleaching teeth stained with coffee meanwhile the KTP laser was efficient at bleaching teeth with coffee, tea and red fruits stains. This study suggests that a relation between the laser wavelength and the type of staining on the dental enamel and the efficacy of the whitening treatment exists.

Susceptibility of teeth to re- pigmentation after bleaching: An in vitro study

Introduction: Whiter or brighter smile, which is a cornerstone of a beautiful esthetic smile, can be achieved by bleaching. The public concern about appearance has been partly responsible for increased awareness in esthetic dentistry and consequently bleaching techniques. Bleaching solutions have been reported to cause alterations and loss of mineral content in surface enamel after bleaching. These irregularities in enamel surface could result in more susceptibility to re-pigmentation, thereby adversely affecting the whitening treatment. Aim: To evaluate the susceptibility of teeth to re-pigmentation using two different bleaching materials, i.e. 35% hydrogen peroxide (H 2 O 2 ) and 16% carbamide peroxide. Subjects and Methods : In this study, 30 extracted teeth were divided in three groups. Group I was bleached with 35% H 2 O 2 , Group II with 16% carbamide peroxide, and Group III was used as control. They were then stained with silver nitrate stain to evaluate their susceptibility to pigmentation after bleaching. The shade of each tooth was recorded before bleaching, after bleaching, and after pigmentation using a Vita shade guide. Results: Results showed that after staining with silver nitrate, the teeth in all groups became darker but the amount of change in the shade value of the samples was different for the two groups. The change of shade was greater for Group I as compared to Group II after pigmentation. This change in shade between Groups I and II was found to be statistically significant using one-way ANNOVA test ( P Conclusions : Thus, we concluded that susceptibility to pigmentation increases after bleaching. Furthermore, pigmentation is greater when H 2 O 2 is used for bleaching.

AVALIAÇÃO PRELIMINAR DA ESTABILIDADE DE EMULSÕES NÃO IÔNICAS CONTENDO ÁCIDO KÓJICO A 2,0 % MANIPULADAS EM FARMÁCIAS MAGISTRAIS

Formulações emulsionadas contendo ácido kójico são comuns entre os produtos cosméticos para clareamento cutâneo. Neste trabalho, avaliou-se a estabilidade preliminar de loções não iônicas contendo ácido kójico a 2,0 %, manipuladas em farmácias magistrais. As formulações foram adquiridas em 04 estabelecimentos farmacêuticos do município de Porto Alegre-RS. As amostras, em frascos de polietileno, foram submetidas à estocagem a 25 e 45ºC e analisadas nos tempos zero, 7, 15, 30 e 60 dias. As amostras foram avaliadas através das seguintes determinações: características organolépticas, pH, teste de centrifugação e determinação de peso da embalagem. Os caracteres organolépticos se apresentaram com modificações a partir de 7 dias de estocagem, em amostras a 45 ºC. Quanto ao pH, as amostras a 45 ºC apresentaram redução do valor inicial, com acréscimo de acidez ao longo do tempo. Neste caso, a centrifugação das amostras não provocou modificação no parâmetro avaliado, nem levou à separação de fases. Para a determinação de peso, os resultados ilustraram uma leve modificação no peso das amostras estocadas a 45 ºC, ilustrando a necessidade de atenção para o material de acondicionamento. Os ensaios desenvolvidos reforçam a importância de atenção na estabilidade de produtos cosméticos contendo ácido kójico, em especial no conhecimento da base galênica e no armazenamento do produto.

Evaluation of the effectiveness of the tooth whitening treatment associated with the immersion in coloring solutions

Tooth whitening or dental bleaching is a cosmetic procedure that has established itself in Dentistry; however, the staining because of the ingestion of some types of food may cause several factors leading to the failure of this treatment. Objective:This study aimed to evaluate in vitro the influence of the immersion of whitened teeth in solutions with a high degree of pigmentation on the efficacy of the bleaching performed with 16% hydrogen peroxide. Material and methods: Fifty-six human teeth were selected, bleached for 4 hours a day during 14 days and randomly divided into 7 groups (n = 8). The groups G1/G2 and G3 were immersed in coloring solutions immediately (IM) after bleaching (AP): G1 – tooth whitening + coffee (IM), G2 – tooth whitening + cola-based soft drink (IM) and G3 – tooth whitening + red wine (IM); G4/and G6 were immersed in the solutions for 2 hours (AP), G4 – tooth whitening + coffee (AP), G5 – tooth whitening + cola based soft drink (AP), G6 – tooth whitening + red wine and (AP) G7 – control. After bleaching with an immersion time of 5 minutes, with the aid of a digital spectrophotometer, the final color (FC) was measured 24 hours after the end of the bleaching treatment (day 15). Results: The results for ANOVA showed no statistical differences in all groups. Conclusion: There was no influence on the effectiveness of tooth whitening immersed in coloring solutions.

Development of a Piezoelectric Ultrasonic Tooth-whitening Apparatus

The aim of this study was to develop an ultrasonic tooth-whitening apparatus using piezoelectric transducers, which enhance bleaching efficiency by applying ultrasound, while performing a teeth whitening procedure. For this purpose, an ultrasonic transducer was designed and manufactured, and the effects of reduction in the whitening material's concentration and in the whitening treatment time through using the ultrasound cavitation phenomenon were confirmed. Also, the validity of this study was investigated by comparing the whitening performance with a commercialized optical whitener, through color comparison. The results revealed that the ultrasound whitener produced color values that were enhanced by as much as double that of the conventional LED light whitening method. Even when the operational time was reduced by half, the ultrasound method showed superior performance by over 54% compared to the conventional light whitener, revealing that the ultrasound method showed a remarkable treatment reduction effect.

Evaluation of metallic brackets adhesion after the use of bleaching gels with and without amorphous calcium phosphate (ACP): in vitro study

To evaluate in vitro the effects of tooth whitening using gel with Amorphous Calcium Phosphate (ACP) on the bond strength of metal brackets. Thirty-six bovine incisors were sectioned at the crown-root interface, and the crowns were then placed in PVC cylinders. The specimens were divided into 3 groups (n = 12) according to whitening treatment and type of gel used, as follows: G1 (control) - no whitening; G2 - whitening with gel not containing ACP (Whiteness Perfect - FGM), G3 - whitening with gel containing ACP (Nite White ACP - Discus Dental). Groups G2 and G3 were subjected to 14 cycles of whitening followed by an interval of 15 days before the bonding of metal brackets. Shear bond strength testing was performed on a Kratos universal test machine at a speed of 0.5 mm/min. After the mechanical test, the specimens were assessed to determine the adhesive remnant index (ARI). The results were subjected to ANOVA, Tukey's test and Kruskal-Wallis test (5%). Significant differences were noted between the groups. Control group (G1 - 11.10 MPa) showed a statistically higher shear bond strength than the groups that underwent whitening (G2 - 5.40 Mpa, G3 - 3.73 MPa), which did not differ from each other. There were no significant differences between the groups in terms of ARI. Tooth whitening reduces the bond strength of metal brackets, whereas the presence of ACP in the whitening gel has no bearing on the results.

Wyman Chan: 'Technically, I have been doing my job illegally for the past 20 years'

Wyman Chan talks to the BDJ about his mission to deliver pain-free whitening treatments and his views on the recent tooth-whitening legislation.

Effect of laser irradiation on crystalline structure of enamel surface during whitening treatment with hydrogen peroxide

ObjectiveThis study is to evaluate the effect of laser activation on the whitening and crystalline structure of enamel surface during whitening treatment with hydrogen peroxide. MethodsBovine teeth were treated with whitening gel containing 35% hydrogen peroxide. A whitening gel was applied on the enamel surface for a period of 5min, and then irradiated using a diode laser (740nm) during whitening treatment for 0, 30, 60, 120 and 180s for the GL0-W, GL30-W, GL60-W, GL120-W and GL180-W groups, respectively. The total whitening application time was 30min for all groups. ResultsLaser-irradiated enamel groups showed a similar lightness compared to the GL0-W group. The thickness of porous layer observed on the enamel surface of GL0-W group was decreased by increasing the laser irradiation time. While the Ca and P contents of the GL0-W group were lower than those of the non-whitening treated group (GL0-C), the Ca and P contents of the GL180-W group were similar to those of the GL180-C group. The enamel crystallinity was dramatically decreased by whitening treatment without laser irradiation. However, the decrease of crystallinity was protected by laser irradiation during whitening treatment. Raman measurement verified that laser irradiation could prevent the loss of mineral compositions on enamel and maintain its crystalline structure. SignificanceThe professional whitening treatment with hydrogen peroxide and diode laser activation improves not only the whitening effect but also protects the change of enamel structure compared to the treatment with only gel.

Comparison of Two At-home Whitening Products of Similar Peroxide Concentration and Different Delivery Methods

This study compared the whitening efficacy, side effects, and patients' preferences/perceptions of two whitening systems of similar peroxide concentration but different formulation and delivery methods. The tooth color change of 24 participants was measured using a shade guide (BSG) and a spectrophotometer (ES). Color difference was calculated: ΔE* = [(ΔL*)(2) + (Δa*)(2) + (Δb*)(2)](1/2). One whitening treatment was randomly applied to the right or left maxillary anterior teeth and the other was applied to the contralateral teeth, at-home with 35% carbamide peroxide in a tray (TW) or with 14% hydrogen peroxide in strips (WS). The tooth color was evaluated at baseline, 15 and 30 days (15 days postwhitening). Participants rated their tooth and soft tissue sensitivity (1-10 scale) and completed a questionnaire on their preferences. Results were analyzed by repeated measurement regression analysis/Tukey and Mann-Whitney (p<0.05). At 15 days, the teeth treated with TW and WS presented ΔE* = 7 and 6, respectively (ΔBSG=3 for both), and at 30 days, they presented ΔE* = 7.5 and 6.5, respectively (ΔBSG=3 for both). There was no significant difference in tooth and soft tissue sensitivity between treatments. No participant reported tooth and gingival sensitivity at the postwhitening appointment. Of the participants, 83% preferred the TW over WS. Both ΔE* and ΔBSG showed no significant difference in tooth color change between TW and SW at either time point. By the end of the study no participants reported tooth and gingival sensitivity. Participants preferred TW over SW.

Patients’ perspective on dental aesthetics in a South-eastern European community

ObjectivesTo assess the importance attributed to dental aesthetics by subjects from a Romanian community. In addition, the role played by dental color, the group-distributions based on the self-evaluation of dental color and the previous experience regarding whitening treatments are analysed. MethodsA multiple-choice questionnaire was administered to 540 patients in dental offices in Cluj-Napoca, Romania; the subjects were also asked to self-evaluate their dental shade, using a set of images as a comparison. Answers to the questionnaires were statistically analysed using Microsoft Excel and SPSS 13.00 (Pearson's chi-square test, Fisher's exact test, Kendall's tau b). ResultsFrom the participants, 17.96% were motivated by aesthetic reasons to ask for treatment; most of the patients evaluated their smile as “acceptable” (38.51%) or “having some defects” (29.44%) and were self-included in groups of medium and dark shades (33.7% and 33.89%, respectively). Whilst 22.40% of the subjects considered the dental color as being the most evident defect of their dentition, 39.07% indicated a self-perception of “an abnormal dental shade”. A strong correlation between darker self-assessed tooth color-groups and the self-perception of an abnormal tooth color was found (Chi square p≪0.001, Kendall's tau-c=0.44, with p≪0.001). Previous whitening treatments were reported by 8.88% of the subjects. ConclusionsAmong patients who wanted to improve one of their oral functions, the majority requested changes in aesthetics. Dental shade is one of the aspects recognized as problematic by the participants, but nonetheless the percentage of patients who had previously benefited by whitening treatments was moderate.

Tooth Whitening of Tetracycline-Stained Teeth

ABSTRACT Tooth discoloration of intrinsic etiology such as from tetracycline ingestion can be a major esthetic problem. This clinical report describes the use of an extended whitening treatment of second-degree tetracycline stained teeth. The suggested combination of in-office and home whitening provided a fast whitening result, proper monitoring of the progress of whitening throughout the extended period, and continuous motivation for the patient to complete the whitening treatment. How to cite this article Kwon SR, Chan DCN. Tooth Whitening of Tetracycline-Stained Teeth. World J Dent 2012;3(3):257-260.

Clinical trial: Photo-Fenton vs. conventional in-office dental whitening treatment

Clinical trial: Photo-Fenton vs. conventional in-office dental whitening treatment

Management of tooth discoloration in non-vital endodontically treated tooth - A report of 6 year follow-up

Discoloration of teeth, especially the anteriors, can result in considerably cosmetic impairment in young children. It is the pediatric dentist’s responsibility to supervise those children who seek to undergo a whitening treatment to ensure the maximum cosmetic benefit within the boundaries of oral and systematic health. Among bleaching tech niques, the walking bleach technique with sodium perborate and distilled water stands out because of its superior esthetic results with no side effects. This paper presents a case of tooth discoloration in non-vital tooth which was successfully bleached using walking bleach method. After 6 year follow up the prognosis was good with no reversal of tooth discoloration and absence of external cervical resorption.

Effect of bleaching versus repolishing on colour and surface topography of stained resin composite

The aim of this study was to examine the effect of ozonated gel, carbamide peroxide bleaching agent and polishing paste on the colour and surface topography of stained resin composite. Ninety disc-shaped resin composite specimens were used in this study. They were randomly divided into three groups of 30 specimens each according to the immersion solutions used, i.e., tea, cola or artificial saliva. Each group was further subdivided into three equal subgroups (n = 10) according to the type of whitening treatment applied; 30% carbamide peroxide, ozonated KY gel or polishing paste. Colour and surface roughness was measured at baseline, after immersion, also following whitening procedures by using a stereomicroscope. The results were recorded, tabulated and statistically analysed. The colour values of artificial saliva displayed the highest statistically significant mean colour difference compared to cola and tea. However, there was no statistically significant difference in surface roughness. Also, a superior whitening effect was demonstrated with ozonated gel. Ozonated gel showed statistically significant lowest roughness compared to both carbamide peroxide and polishing paste. Immersion solutions have a positive influence on the colour of resin composite. Also, ozonated gel is an efficient bleaching agent with the least adverse effect on surface roughness.