Bleaching of fluorosis stains using sodium hypochlorite

Comparative Effects of Three Bleaching Techniques on Tooth Discoloration Caused by Tea

Objectives: This study aimed to investigate the impact of three different bleaching protocols on tooth discoloration caused by tea. Materials and Methods: Forty extracted sound premolars were cleaned, disinfected, and their initial color parameters were measured (T1). The teeth were then immersed in boiled tea solution for 24 hours, and their color was measured again (T2). The samples were divided into four groups of 10 teeth each. Group A was treated with an in-office bleaching gel followed by 30 seconds of light curing. Groups B, C, and D were respectively treated with 0.24M oxalic acid followed by bleaching gel, 5.25% sodium hypochlorite followed by bleaching gel, and a combination of 0.24M oxalic acid, 5.25% sodium hypochlorite, and bleaching gel. The color was measured once more after the interventions (T3). Data were analyzed using two-way repeated measures ANOVA, paired sample t-test, and Tukey's test. Results: The mean color change (∆E2) between T2 and T3 was significantly higher in group D compared to group A (P<0.05). However, there was no significant difference in color change between groups A, B, and C. Additionally, there was no significant difference in color change between groups B, C, and D. The groups also showed significant differences in ∆L (P=0.007), with the only significant difference found between groups B and C (P=0.001). Conclusion: The combined use of sodium hypochlorite and oxalic acid followed by in-office bleaching gel is more effective than bleaching alone in correcting tooth discoloration caused by tea. This protocol can further reduce yellow coloration.

Conservative esthetic management of brown enamel fluorosis using combination therapy: A clinical report

Dental fluorosis is caused by ingestion of excessive fluoride during tooth development resulting in hypomineralization of the enamel and can present as white or brown intrinsic lesions. This case report describes a combination of minimally invasive techniques: microabrasion, bleaching, and resin infiltration to address brown enamel fluorosis present on the maxillary anterior teeth of a young patient. Before resin infiltration, air microabrasion was targeted at subsurface lesions located on the maxillary central and lateral incisors, and chairside bleaching was done with 37% hydrogen peroxide (Opalescence). After which, hypoplastic lesions on the buccal surfaces were etched before being treated with two sessions of resin infiltration (ICON and DMG). Following treatment, satisfactory esthetic outcomes were achieved. Accurate diagnosis, depth of lesions, and understanding the effectiveness and limitations of each technique are essential to select the appropriate type of treatment to obtain the best esthetic outcome. In conclusion, the conservative management of varying severity of dental fluorosis may require the appropriate use of combination treatment modalities, such as microabrasion, bleaching and resin infiltration, when clinically indicated, to address the treatment needs and achieve a desired outcome.

Adhesion and whitening efficacy of P11-4 self-assembling peptide and HAP suspension after using NaOCl as a pre-treatment agent

Background

This study evaluated the adhesion and whitening efficacy of a mixture of hydroxyapatite and P11-4 self-assembling peptide (HAP-peptide) on bovine enamel after pre-treatment with low-concentrated sodium hypochlorite (NaOCl).

Methods

Fifty-two caries-free bovine incisors were selected. 50 teeth were randomly allocated to five groups (n = 10). The first group was treated with a mixture of 6.25 wt% HAP and 5 ml P11-4 peptide, using NaOCl 3% as pre-treatment. Second, third and fourth groups were treated with 6.25 wt% HAP, 5 ml P11-4 peptide, and NaOCl 3%, respectively. In the fifth group, only water was applied (control group). The color of samples was measured using a spectrophotometer (USB4000-VIS-NIR-ES, Ostfildern, Germany). To evaluate color changes, ΔE values were statistically analyzed. Finally, adherence of HAP particles on two enamel surfaces with and without pre-treatment with NaOCl was analyzed with SEM.

Results

It was observed that the ΔE of the HAP-peptide suspension after pre-treatment with NaOCl was significantly stronger than the control group. In contrast, the overall color changes of separate applications of HAP, peptide, and NaOCl did not differ notably from the control group. SEM observations confirmed that pre-treatment with NaOCl resulted in a more pronounced coverage of HAP on the enamel surface.

Conclusions

Pre-treatment with a low-concentrated NaOCl enhanced the adherence of the HAP layer on the enamel surface, resulting in a stronger whitening effect.

Trial registration

The peptide-HAP suspension is effective in improving tooth whiteness.

Resin infiltration and remineralization interventions in management of moderate dental fluorosis: A quantitative light-induced fluorescence-based randomized controlled trial

Context

Aesthetic concerns due to dental fluorosis (DF) considerably impact pyschosocial health in young children and requires aesthetic microinvasive treatment.

Aims

The aim of this study was to use quantitative light-induced fluorescence to evaluate two intervention protocols: microabrasion with resin infiltration and microabrasion with remineralization and assess which brings about more fluorescence gain; better colour masking and greater patient satisfaction among subjects with dental fluorosis.

Methods and Material

120 maxillary central incisors with Grade 3 DF (Dean's Fluorosis Index) were randomly distributed into four groups: I-microabrasion + resin infiltration (fluorosis with stains); II microabrasion + remineralization (fluorosis with stains); III-microabrasion + resin infiltration (fluorosis without stains); IV microabrasion + remineralization (fluorosis without stains). At baseline, post-microabrasion and post-intervention Quantitative light-induced fluorescent images were captured. Fluorescence gain (ΔF) was analysed from the blue light images. The white light images were used to evaluate post intervention colour difference (ΔE = [(ΔL*) 2+(Δa*) 2+(Δb*) 2]1/2) and child satisfaction was evaluated.

Statistical Analysis Used

Collected data was analysed using repeated measures ANOVA and Independent t-test.

Results

Intra-group comparison of ΔF values showed statistically significant improvement in ΔF value in all the four groups (P < 0.001, 0.002). Inter-group comparison of ΔF values based on intervention showed statistically significant fluorescence gain (P < 0.004) indicating resin infiltration intervention being better than remineralization in unstained grade III fluorosis. The colour difference was statistically significantly better with resin infiltration in both stained and unstained Grade III DF (P < 0.001).

Conclusions

Resin infiltration intervention showed better fluorescence gain and colour masking compared to remineralization intervention.

Effect of mangosteen peel extract as an antioxidant agent on the shear bond strength of orthodontic brackets bonded to bleached teeth

Introduction:

The number of patients who seek orthodontic treatment that may have a history of tooth bleaching is increasing over the time. Bleaching may influence the decrease of the bond strength of orthodontic brackets.

Objective:

To determine and prove the effect of mangosteen peel (MP) extract to reverse the reduced shear bond strength (SBS) of orthodontic brackets after bleaching.

Methods:

A total of 150 maxillary first premolar teeth were randomly divided into 6 experimental groups as follow (n=25): negative-control (N: no bleaching), positive-control (P: bleaching + no treatment), and the treatment groups (bleaching + 10% sodium ascorbate (SA), 10% (MP-10), 20% (MP-20) and 40% (MP-40) MP extract gel). After treatment, the brackets were bonded with the resin-modified glass ionomer cement, SBS testing was performed using universal testing machine, and the adhesive remnant index (ARI) was examined using stereoscopic microscope after debonding. The SBS data were analyzed by analysis of variance (Anova) and the Tukey test. For the ARI, the Kruskal-Wallis test was performed.

Result:

There was significant SBS difference (p< 0.001) between various groups. The group without bleaching showed significantly higher SBS (8.19 ± 2.26 MPa) compared to others, while SBS in the group treated with 40% MP gel was significantly higher (7.93 ± 1.92 MPa) than other groups treated with antioxidants. The failure of orthodontic brackets bonded after bleaching and treatment using MP extract occurred at the enamel-adhesive interface.

Conclusion:

The application of MP extract as an antioxidant after bleaching was effective in reversing the reduced shear bond strength of orthodontic brackets after bleaching.

Comparative evaluation of esthetic changes in nonpitted fluorosis stains when treated with resin infiltration, in-office bleaching, and combination therapies

OBJECTIVES

Dental fluorosis leads to esthetic deviation and varies from nonpitted white opacities, dark brown stains to pitting or structural breakdown of enamel surface. Treatment for fluorosis depends on the severity of condition and includes both noninvasive methods and invasive methods. Recently resin infiltration has been proposed as an alternative treatment for nonpitted fluorosis. This study was done to evaluate the esthetic changes in nonpitted fluorosis stains when treated with resin infiltration, in-office bleaching and combination therapies.

MATERIALS AND METHODS

The present study is a randomized, single blinded controlled trial with four parallel arms with 1:1 allocation ratio. The intervention arms included bleaching with 35% hydrogen peroxide, resin infiltration, resin infiltration with increased infiltration time and a combination approach of bleaching and infiltration. Immediate esthetic changes were evaluated for two parameters including, 'Change in esthetics' and 'Improvement in opacities/stains' using a VAS scale by two independent observers. Kruskal-Wallis test and Mann-Whitney U-test were done for intergroup comparisons.

RESULTS

Best results for both the parameters were observed among patients treated with resin infiltration with increased infiltration time. Mann-Whitney U test revealed significantly better results for resin infiltration groups (alone or combination with bleaching) as compared to bleaching alone (P < .001).

CONCLUSIONS

Resin infiltration procedure with tailored etching times and increased infiltration time exhibited best results in terms of change in esthetics and improvement in stains.

CLINICAL SIGNIFICANCE

White and brown opacities due to fluorosis have always been a concern for esthetics. In our study, resin infiltration technique with tailored etching times and increased infiltration time exhibited best immediate esthetic improvement for nonpitted fluorotic opacities and stains. These esthetic outcomes reaffirm the applicability of RI technique for nonpitted fluorosis, which was originally advocated only for white spot lesions due to early caries. This will in turn help the dentists to plan the esthetic management of nonpitted fluorosis in a micro-invasive manner.

A Novel Biomimetic Approach to Repair Enamel Cracks/Carious Damages and to Reseal Dentinal Tubules by Amorphous Polyphosphate

Based on natural principles, we developed a novel toothpaste, containing morphogenetically active amorphous calcium polyphosphate (polyP) microparticles which are enriched with retinyl acetate ("a-polyP/RA-MP"). The spherical microparticles (average size, 550 ± 120 nm), prepared by co-precipitating soluble Na-polyP with calcium chloride and supplemented with retinyl acetate, were incorporated into a base toothpaste at a final concentration of 1% or 10%. The "a-polyP/RA-MP" ingredient significantly enhanced the stimulatory effect of the toothpaste on the growth of human mesenchymal stem cells (MSC). This increase was paralleled by an upregulation of the MSC marker genes for osteoblast differentiation, collagen type I and alkaline phosphatase. In addition, polyP, applied as Zn-polyP microparticles ("Zn-a-polyP-MP"), showed a distinct inhibitory effect on growth of Streptococcus mutans, in contrast to a toothpaste containing the broad-spectrum antibiotic triclosan that only marginally inhibits this cariogenic bacterium. Moreover, we demonstrate that the "a-polyP/RA-MP"-containing toothpaste efficiently repairs cracks/fissures in the enamel and dental regions and reseals dentinal tubules, already after a five-day treatment (brushing) of teeth as examined by SEM (scanning electron microscopy) and semi-quantitative EDX (energy-dispersive X-ray spectroscopy). The occlusion of the dentin cracks by the microparticles turned out to be stable and resistant against short-time high power sonication. Our results demonstrate that the novel toothpaste prepared here, containing amorphous polyP microparticles enriched with retinyl acetate, is particularly suitable for prevention/repair of (cariogenic) damages of tooth enamel/dentin and for treatment of dental hypersensitivity. While the polyP microparticles function as a sealant for dentinal damages and inducer of remineralization processes, the retinyl acetate acts as a regenerative stimulus for collagen gene expression in cells of the surrounding tissue, the periodontium.