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1.
Braz. j. oral sci ; 20: e213859, jan.-dez. 2021. ilus
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1253923

RESUMO

Aim: This study evaluated the effect of a desensitizer agent (DES) during bleaching with 10% carbamide peroxide (CP) on enamel microshear bond strength (µSBS). Methods: Sixty bovine incisors were obtained and randomly distributed into groups (n=15): (C) Control: no desensitizing or bleaching, (DES) desensitizing gel application, (CP) bleaching with 10% CP and (CP/DES) bleaching with 10% CP combined with DES. Bleaching was performed for 6 h/day for 14 consecutive days. DES was applied for 8 h only on the 7th and 14th days of therapy. Specimens were stored in artificial saliva among the CP or DES applications and submitted to µSBS testing at three postrestoration times (n=5): 24 h, 7 days, and 14 days after bleaching using a universal testing machine. Failure modes were observed under a stereomicroscope. Data were analyzed by two-way ANOVA and Tukey's test (α=5%). Results: Immediately after bleaching (24 h), CP promoted lower µSBS than the C and DES groups (p<0.05) but with no differences from the CP/DES. µSBS increased in the DES, CP, and CP/DES groups (p<0.05) when bonding was performed for 7 or 14 days elapsed from bleaching. CP/DES exhibited the highest µSBS among the groups 14 days after bleaching (p<0.05). Cohesive failure in enamel was predominant in the CP groups, while adhesive failure was mostly observed for the other groups. Conclusion: The use of a desensitizer during at-home bleaching maintained the enamel immediate bond strength, and its application favored bonding when the restoration was delayed for 14 days


Assuntos
Animais , Bovinos , Clareamento Dental , Esmalte Dentário , Resistência ao Cisalhamento
2.
Braz Dent J ; 32(3): 105-115, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34755785

RESUMO

This clinical trial evaluated the effect of the coadministration of ibuprofen/caffeine on bleaching-induced tooth sensitivity (TS). A triple-blind, parallel-design, randomized clinical trial was conducted on 84 patients who received ibuprofen/caffeine or placebo capsules. The drugs were administered for 48 hours, starting 1 hour before the in-office bleaching. Two bleaching sessions were performed with 35% hydrogen peroxide gel with 1-week interval. TS was recorded up to 48 hours after dental bleaching with a 0-10 visual analogic scale (VAS) and a 5-point numeric rating scale (NRS). The color was evaluated with VITA Classical and VITA Bleachedguide scales (ΔSGU) and VITA Easyshade spectrophotometer (ΔE*ab and ΔE00). The absolute risk of TS in both groups was evaluated using Fischer's exact test. Comparisons of the TS intensity (NRS and VAS data) were performed by using the Mann-Whitney test and a two-way repeated measures ANOVA, respectively. The color alteration between the groups was compared with the Student's t test. The significance level was 5%. There was no statistically significant difference between the groups for the absolute risk of TS (p = 1.00) or for the intensity of TS (p > 0.05). A bleaching of approximately 7 shade guide units was observed on the Vita Classical and Vita Bleachedguide scales, with no statistical difference between the groups. It was concluded that coadministration of ibuprofen and caffeine did not reduce the absolute risk or intensity of TS and did not interfere with the efficacy of dental bleaching.


Assuntos
Cafeína/uso terapêutico , Sensibilidade da Dentina , Ibuprofeno/uso terapêutico , Clareadores Dentários , Clareamento Dental , Sensibilidade da Dentina/induzido quimicamente , Humanos , Peróxido de Hidrogênio , Clareadores Dentários/efeitos adversos , Resultado do Tratamento
3.
Braz Dent J ; 32(4): 19-30, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34787248

RESUMO

This study investigated the bleaching effectiveness and the physicochemical effects on enamel of violet light and ozone, associate or not to hydrogen peroxide, compared to 35%-hydrogen peroxide. Enamel-dentin blocks from human molars were randomly allocated to receive one of the following bleaching protocols (n=15): (HP) 35%-hydrogen peroxide, (VL) violet light, (OZ) ozone, the association between hydrogen peroxide with ozone (OZ+HP) or violet light (VL+HP). All protocols were performed in two sessions with a 48h interval. Color (spectrophotometer) and mineral composition (Raman spectroscopy) were measured before and after the bleaching. Color changes were calculated by ΔEab, ΔE00, and whitening index (WI). The surface roughness was measured with an atomic force microscope. Data were analyzed by One-way or Two-way repeated measure ANOVA followed by the Tukey's test (α = 0.05). The lowest color change values (either measured by WI, ΔEab, or ΔE00) were observed for VL and OZ used with no HP. Violet light associate with HP was unable to improve the color changes observed for the peroxide alone, in combination with OZ and HP, the highest color changes were verified. Regardless of bleaching protocol, the bleached enamel presented higher contents of PO4 and CO3 -2 than those observed at baseline. All bleaching protocols resulted in similar enamel surface roughness. Both the VL and the OZ caused reduced effects on the enamel color change when used alone. The ozone therapy improved the bleaching effect in the group that received the association of HP.


Assuntos
Ozônio , Clareadores Dentários , Clareamento Dental , Cor , Esmalte Dentário , Humanos , Peróxido de Hidrogênio
4.
Braz Oral Res ; 35: e113, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34816901

RESUMO

The ultrastructural and mechanical properties of enamel surface were evaluated after prolonged bleaching treatments with 10% carbamide peroxide in the presence or absence of orange juice (erosive challenge) and toothbrushing (abrasive challenge). In total, 145 incisor bovine teeth were used in this study. Twenty-five samples were prepared for the ultrastructural evaluations, and 120 samples were prepared for microhardness and roughness tests. These 120 samples were divided into eight experimental groups (n = 15): G1- artificial saliva; G2- abrasion; G3- erosion; G4- dental bleaching; G5- erosion + abrasion; G6- bleaching + abrasion; G7- bleaching + erosion; and G8- bleaching + erosion + abrasion. All groups were tested at T0 (before treatment), T1 (14 days), T2 (21 days), and T3 (28 days). Two-way analysis of variance for repeated measures and the post hoc Sidak tests (p ≤ 0.05) were used. The roughness evaluation demonstrated an increase in damage for all experimental groups with an increase in the time period. For microhardness, the groups exposed to artificial saliva (AS) and abrasive challenge did not show any differences at any time points, while the other groups showed a decrease in microhardness from T0 to T3. Ultrastructural evaluation showed different surface alterations in response to the treatments. Despite prolonged bleaching periods, the procedure caused lesser enamel surface alterations than exposure to orange juice alone or in combination with brushing.


Assuntos
Clareamento Dental , Animais , Peróxido de Carbamida , Bovinos , Esmalte Dentário , Hábitos , Clareamento Dental/efeitos adversos , Escovação Dentária
5.
Am J Dent ; 34(5): 281-285, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34689453

RESUMO

PURPOSE: To evaluate the bleaching sensitivity and the bleaching effectiveness of in-office bleaching, following a protocol of complete cervical third protection with gingival dam in comparison with a traditional manner of applying gingival dam (used only in the gingival sulcus area). METHODS: 35 participants were selected for this double-blind split-mouth randomized clinical trial. The control group received the gingival barrier in the traditional manner, and in the experimental group the barrier was extended by about 3 mm to include the cervical region. The bleaching agent was applied in two sessions. The risk and intensity of bleaching sensitivity were assessed using two scales. The bleaching effectiveness was evaluated with a digital spectrophotometer with the tip placed in the cervical area. The absolute risk of bleaching sensitivity was compared by the McNemar's test and bleaching effectiveness (ΔEab, ΔE00 and ΔWi) and intensity of bleaching sensitivity was evaluated by Wilcoxon-paired test (α= 0.05). RESULTS: No significant difference at risk (P= 1.0) and intensity of bleaching sensitivity (P> 0.45) was seen between groups. After 30 days, bleaching effectiveness had no statistical difference between the groups (P> 0.09). CLINICAL SIGNIFICANCE: Extending the barrier in the cervical region of teeth did not reduce the risk and intensity of bleaching sensitivity, nor jeopardize the bleaching effectiveness.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Sensibilidade da Dentina/prevenção & controle , Humanos , Peróxido de Hidrogênio , Boca , Ensaios Clínicos Controlados Aleatórios como Assunto , Clareamento Dental/efeitos adversos , Clareadores Dentários/efeitos adversos , Resultado do Tratamento
6.
Biomed Res Int ; 2021: 3766641, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34471637

RESUMO

Tooth bleaching is becoming increasingly popular among patients with tooth staining, but the safety of bleaching agents on tooth structure has been questioned. Primarily thriving on the biofilm formation on enamel surface, Streptococcus mutans has been recognized as a major cariogenic bacterial species. The present study is aimed at investigating how cold-light bleaching would change enamel roughness and adhesion of Streptococcus mutans. Human premolars were divided into 72 enamel slices and allocated into 3 groups: (1) control, (2) cold-light bleaching with 35% hydrogen peroxide (Beyond™), and (3) 35% hydrogen peroxide (Beyond™) alone. Biofilms of Streptococcus mutans were cultivated on enamel slices in 5% CO2 (v/v) at 37°C for 1 day or 3 days. Enamel surfaces and biofilms were observed using scanning electron microscope (SEM). Atomic force microscopy (AFM) was applied to quantify the roughness of enamel surface, and the amounts of biofilms were measured by optical density of scattered biofilm and confocal laser scanning microscopy (CLSM). Cold-light bleaching significantly increased (p < 0.05) surface roughness of enamel compared to controls, but significantly inhibited (p < 0.05) adhesion of Streptococcus mutans on enamel in the bacterial cultures of both 1 day and 3 days. In conclusion, cold-light bleaching could roughen enamel surface but inhibit Streptococcus mutans adhesion at the preliminary stage after the bleaching treatment.


Assuntos
Esmalte Dentário/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Streptococcus mutans/efeitos dos fármacos , Streptococcus mutans/fisiologia , Clareamento Dental/métodos , Dente/efeitos dos fármacos , Dente/microbiologia , Aderência Bacteriana , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Esmalte Dentário/microbiologia , Esmalte Dentário/patologia , Humanos , Luz , Microscopia de Força Atômica/métodos , Medicamentos Compostos contra Resfriado, Influenza e Alergia , Propriedades de Superfície , Dente/patologia
7.
J Clin Pediatr Dent ; 45(4): 253-258, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34534304

RESUMO

INTRODUCTION: Discoloration of anterior teeth can result in cosmetic impairment in young children. The walking bleach technique stands out because of its esthetic results with minor side effects. Little information is available regarding the influence of various irrigation solutions on peroxide penetration. The aim of this study is to evaluate the influence of different irrigation protocols on peroxide penetration into dentinal tubules using confocal laser scanning microscopy (CLSM). STUDY DESIGN: Cavity preparations were made in 50 extracted permanent premolars. The teeth went through different irrigation sequences: A. control B. saline C. EDTA, NaOCl D. phosphoric acid E. EDTA, NaOCl, phosphoric acid. Then, mixture of fluorescent dyed sodium perborate paste was placed along the pulp chamber and the coronal access cavity, and was refilled at days 7, 14 and 21. RESULTS: The minimal and maximal penetration depths were 324 and 3045 µm, respectively, with a mean of 1607µm. The stained areas were significantly larger in the buccal and lingual directions (P<0.05). Groups B and C showed significantly larger penetration in weeks 2 and 3 compared to week 1 (P<0.05). Group D and E showed significantly larger penetration compared to groups B and C at all times (P<0.05). CONCLUSION: Bleaching agents penetrate to the extra-radicular region of teeth; however, the level of peroxide penetration is significantly higher when the irrigation sequence consists of phosphoric acid prior the bleaching agent placement.


Assuntos
Peróxidos , Clareamento Dental , Criança , Pré-Escolar , Cavidade Pulpar , Humanos , Microscopia Confocal , Irrigantes do Canal Radicular , Hipoclorito de Sódio
8.
Dental Press J Orthod ; 26(4): e2119124, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34468559

RESUMO

OBJECTIVE: The aim of this experimental in vitro study was to evaluate whether dental bleaching performed before orthodontic treatment change the shear bond strength (SBS) of monocrystalline and polycrystalline esthetic brackets. METHODS: Sixty (60) bovine incisors teeth were used and randomly divided into the following six groups (n=10): SCP (without bleaching/polycrystalline brackets); SCM (without bleaching/monocrystalline brackets); 1CP (one bleaching session/polycrystalline brackets); 1CM (one bleaching session/monocrystalline brackets); 3CP (three bleaching sessions/polycrystalline brackets); and 3CM (three bleaching sessions/monocrystalline brackets). The brackets were bonded seven days after the bleaching sessions. The samples were submitted to the SBS test in a universal testing machine (Instron model 4411) at 1 mm/min crosshead speed. The two-way analysis of variance (ANOVA) and the Tukey tests were performed at a 5% level of significance. After the mechanical test, samples were evaluated to determine the adhesive remnant index (ARI). RESULTS: The SBS values were significantly higher for the monocrystalline brackets, when compared with the polycrystalline type (p< 0.0001), and significantly higher with three bleaching sessions than without bleaching (p< 0.0436). The ARI showed predominance of failures between the bracket and resin for all the groups (score 3). CONCLUSION: Three dental bleaching sessions increased the SBS values. Monocrystalline brackets showed higher SBS values than the polycrystalline type.


Assuntos
Colagem Dentária , Braquetes Ortodônticos , Clareamento Dental , Animais , Bovinos , Análise do Estresse Dentário , Estética Dentária , Teste de Materiais , Cimentos de Resina , Resistência ao Cisalhamento
9.
Sci Rep ; 11(1): 17418, 2021 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-34465829

RESUMO

Hyperalgesia has become a major problem restricting the clinical application of tooth bleaching. We hypothesized that transient receptor potential ankyrin 1 (TRPA1), a pain conduction tunnel, plays a role in tooth hyperalgesia and inflammation after bleaching. Dental pulp stem cells were seeded on the dentin side of the disc, which was cut from the premolar buccal tissue, with 15% (90 min) or 40% (3 × 15 min) bleaching gel applied on the enamel side, and treated with or without a TRPA1 inhibitor. The bleaching gel stimulated intracellular reactive oxygen species, Ca2+, ATP, and extracellular ATP in a dose-dependent manner, and increased the mRNA and protein levels of hyperalgesia (TRPA1 and PANX1) and inflammation (TNFα and IL6) factors. This increment was adversely affected by TRPA1 inhibitor. In animal study, the protein levels of TRPA1 (P = 0.0006), PANX1 (P < 0.0001), and proliferation factors [PCNA (P < 0.0001) and Caspase 3 (P = 0.0066)] increased significantly after treated rat incisors with 15% and 40% bleaching gels as detected by immunohistochemistry. These results show that TRPA1 plays a critical role in sensitivity and inflammation after tooth bleaching, providing a solid foundation for further research on reducing the complications of tooth bleaching.


Assuntos
Polpa Dentária/patologia , Hiperalgesia/patologia , Inflamação/patologia , Espécies Reativas de Oxigênio/metabolismo , Células-Tronco/patologia , Clareadores Dentários/efeitos adversos , Clareamento Dental/efeitos adversos , Animais , Cálcio/metabolismo , Polpa Dentária/efeitos dos fármacos , Polpa Dentária/metabolismo , Géis/efeitos adversos , Hiperalgesia/induzido quimicamente , Hiperalgesia/metabolismo , Inflamação/induzido quimicamente , Inflamação/metabolismo , Ratos , Ratos Sprague-Dawley , Células-Tronco/efeitos dos fármacos , Células-Tronco/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
10.
Hua Xi Kou Qiang Yi Xue Za Zhi ; 39(4): 453-457, 2021 Aug 01.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-34409802

RESUMO

OBJECTIVES: This work aimed to evaluate the ability of two kinds of antioxidants, namely, grape-seed extract and sodium ascorbate, in restoring bond strength at the resin-enamel interface after bleaching. METHODS: Ten groups of samples with 15 teeth per group were prepared for shear-bond-strength test at the resin-enamel interface after bleaching. The groups were as follows: control; no antioxidant; 2.5%, 5%, 10%, or 15% grape-seed extract; and 2.5%, 5%, 10%, or 15% sodium ascorbate. The peak values of shear bond strength when resin was debonded from teeth and the failure modes under a microscope were recorded. Ten other groups of teeth with two teeth per group were prepared and treated in a similar approach before resin bonding. The samples were cut vertically to the bonding interface. The structures of the bonding interface were compared by scanning electron microscopy. RESULTS: No statistically significant difference in shear bond strength was found among the no-antioxidant, 2.5% grape-seed extract, and 2.5%, 5%, or 10% sodium ascorbate groups (P>0.05), which were statistically significantly lower than the control group (P<0.05). Evidence of marginal gap was observed at the resin-enamel interface, and resin tags in enamel were short, poorly defined, and fragmented. No statistically significant difference in shear bond strength was found among 5%, 10%, or 15% grape-seed extract, 15% sodium ascorbate, and control groups (P>0.05). No evidence of discontinuity was found at the adhesion interface, and resin tags in enamel were long, well defined, and structurally intact. Failure in the adhesive joint was the major debond mode in all experimental groups. CONCLUSIONS: Immediately after bleaching, the bond strength of dental enamel significantly decreased. Bond strength can be restored by 5% grape-seed extract or 15% sodium ascorbate in 5 min.


Assuntos
Colagem Dentária , Clareamento Dental , Antioxidantes , Resinas Compostas , Cimentos Dentários , Esmalte Dentário , Humanos , Resistência ao Cisalhamento
11.
Am J Dent ; 34(4): 201-204, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34370912

RESUMO

PURPOSE: To evaluate the influence of light irradiation on the clinical efficiency of an in-office whitening agent. METHODS: The in-office whitening agent (Opalescence Boost 35%) was used in this study. Two whitening regimens were evaluated on maxillary anterior teeth: (1) with light irradiation; and (2) without light irradiation. The ΔE*, changes of L*, a*, b*, and the best shade match on the central incisor before, immediately after, and 6 months after whitening procedures were evaluated using a dental spectrophotometer. RESULTS: The ΔE and shade had no significant differences with or without light irradiation. In addition, the ΔE, changes of L*, a*, b*, and shade did not change over 6 months after bleaching at a level detectable to the naked eye. The results suggested that the in-office whitening agent using 35% hydrogen peroxide without photocatalysts can improve tooth color with or without light irradiation for 6 months after whitening. CLINICAL SIGNIFICANCE: In office whitening using 35% hydrogen peroxide without photocatalysts should be considered as a good treatment option for vital teeth whitening.


Assuntos
Clareadores Dentários , Clareamento Dental , Dente , Cor , Humanos , Peróxido de Hidrogênio , Clareadores Dentários/uso terapêutico
12.
Am J Dent ; 34(4): 215-221, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34370915

RESUMO

PURPOSE: To evaluate whether adding calcium and phosphorus-containing salts to 35% hydrogen peroxide at saturation concentrations with respect to hydroxyapatite would reduce its deleterious effects on bleached enamel or affect bleaching efficacy. METHODS: The saturation concentrations of elemental calcium and phosphorus in a 35% hydrogen peroxide solution were determined after equilibration with powdered enamel. The solubility limit of the salts in 35% hydrogen peroxide was then experimentally determined. Polished bovine enamel-dentin specimens (n=120) with known baseline enamel Knoop microhardness (KHN), surface roughness (Ra), and color were bleached with hydrogen peroxide containing different concentrations of calcium and phosphorus-containing salts as follows: Negative Control - water without any addition; Positive Control - 35% hydrogen peroxide without any addition; 50% of Ca and P - hydrogen peroxide with calcium and phosphorus-containing salt additions of 50% of the saturation concentration; 100% of Ca and P - hydrogen peroxide with calcium and phosphorus-containing salt additions of 100% of the saturation concentration; Ca limit - hydrogen peroxide with addition of calcium-containing salt at the solubility limit, and P limit - hydrogen peroxide with addition of phosphate-containing salt at the solubility limit. The prepared bleaching solutions were applied on the surface of the specimens for 60 minutes. The microhardness and surface roughness were measured immediately after bleaching, and the color change (ΔE*00) was evaluated after 7 days. RESULTS: One-way ANOVA showed significant differences among the groups for all evaluations (P< 0.05). The groups saturated with elemental calcium and/or phosphorus with respect to hydroxyapatite did not show significant changes in microhardness and roughness in relation to the negative control, while the positive control without mineral supplementation and the 50% saturated group showed reduced microhardness and increased roughness. The addition of calcium and/or phosphorus-containing salts in sufficient concentrations to create a saturated hydrogen peroxide solution with respect to hydroxyapatite was able to completely prevent surface changes without affecting the bleaching effect. CLINICAL SIGNIFICANCE: The addition of ions at saturation concentrations or higher with respect to hydroxyapatite can prevent enamel demineralization without compromising the efficacy of bleaching gels.


Assuntos
Clareadores , Clareadores Dentários , Clareamento Dental , Animais , Cálcio , Bovinos , Esmalte Dentário , Dureza , Peróxido de Hidrogênio , Fósforo , Sais , Clareadores Dentários/farmacologia
13.
Oper Dent ; 46(2): 143-150, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34464978

RESUMO

OBJECTIVE: This single-blind, split-mouth, randomized trial was aimed at evaluating the bleaching efficacy (BE) and tooth sensitivity (TS) of a 20% hydrogen peroxide (HP) bleaching agent used under active or passive application. METHODS AND MATERIALS: Twenty-two patients with canines darker than C2 were selected. Teeth were bleached in two sessions, with a one-week interval between treatments. The bleaching agent was applied using active (HPactive) or passive (HPpassive) application. Each tooth in the HPactive-allocated hemiarch received bleaching gel with sonic activation after 10 and 30 minutes from the start of treatment, with rounded movements all over the buccal surface. The color changes were evaluated by subjective (Vita Classical and Vita Bleachedguide) and objective (VITA Easyshade Spectrophotometer) methods at baseline and 30 days after the second session. TS was recorded up to 48 hours after treatment using a 0-10 visual analog scale. Color change in shade guide units (SGUs) and ΔE was analyzed using a Wilcoxon test (α=0.05). The absolute risk and intensity of TS were evaluated using McNemar test and a Wilcoxon test, respectively (α=0.05). RESULTS: Significant whitening was observed in both groups after 30 days of clinical evaluation. The activation did not significantly influence BE (ΔSGU HPpassive=5.6 and HPActive=5.8; p=0.98; and ΔE HPpassive=10.6 and HPactive=10.3; p=0.83). Absolute risk of TS (HPactive=36.4% and HPpassive=31.8%; p=0.94) was similar for both groups (Fisher exact test). TS intensity (visual analogue scale) was higher during the bleaching sessions and up to 24 hours thereafter for both groups, with no differences between groups (two-way analysis of variance and Tukey). CONCLUSION: The active application of a 20% HP gel did not improve BE and TS.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Sensibilidade da Dentina/induzido quimicamente , Humanos , Peróxido de Hidrogênio , Método Simples-Cego , Clareadores Dentários/uso terapêutico , Resultado do Tratamento
14.
J Esthet Restor Dent ; 33(7): 1045-1050, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34383366

RESUMO

OBJECTIVE: To identify the hue angles that provide the optimal perception of tooth whitening. METHODS: Thirty-three male/female adult observers with normal color vision were recruited to assess teeth images on a color calibrated display. Images of teeth were generated which simulated color changes in each of eight hue directions in the CIE a*b* plane, each equi-distant from a baseline tooth color. Using a paired comparison study design, observers were asked to indicate which of two images had whiter teeth. The data were converted into an interval scale using Thurstone's Law of Comparative Judgment. The relationship between the hue angles and the scores was modeled by curve fitting. RESULTS: The optimal hues were found in a region between green and blue in the CIE a*b chart. When the tooth color travels in an optimal hue direction, the same amount of color change will result in a greater change in whiteness perception than when traveling in other hue directions. CONCLUSIONS: The optimal hues for tooth whitening were identified from the visual perception study. The most effective tooth whitening direction is to change tooth color towards the greenish-blue hue direction. CLINICAL SIGNIFICANCE: This study gives clinicians and researchers a better understanding of tooth color hue effects in tooth whiteness perception.


Assuntos
Clareamento Dental , Dente , Cor , Percepção de Cores , Feminino , Humanos , Masculino , Percepção Visual
15.
Braz. dent. j ; 32(4): 19-30, July-Aug. 2021. tab, graf
Artigo em Inglês | LILACS, BBO - Odontologia | ID: biblio-1345519

RESUMO

Abstract: This study investigated the bleaching effectiveness and the physicochemical effects on enamel of violet light and ozone, associate or not to hydrogen peroxide, compared to 35%-hydrogen peroxide. Enamel-dentin blocks from human molars were randomly allocated to receive one of the following bleaching protocols (n=15): (HP) 35%-hydrogen peroxide, (VL) violet light, (OZ) ozone, the association between hydrogen peroxide with ozone (OZ+HP) or violet light (VL+HP). All protocols were performed in two sessions with a 48h interval. Color (spectrophotometer) and mineral composition (Raman spectroscopy) were measured before and after the bleaching. Color changes were calculated by ΔEab, ΔE00, and whitening index (WI). The surface roughness was measured with an atomic force microscope. Data were analyzed by One-way or Two-way repeated measure ANOVA followed by the Tukey's test (α = 0.05). The lowest color change values (either measured by WI, ΔEab, or ΔE00) were observed for VL and OZ used with no HP. Violet light associate with HP was unable to improve the color changes observed for the peroxide alone, in combination with OZ and HP, the highest color changes were verified. Regardless of bleaching protocol, the bleached enamel presented higher contents of PO4 and CO3 -2 than those observed at baseline. All bleaching protocols resulted in similar enamel surface roughness. Both the VL and the OZ caused reduced effects on the enamel color change when used alone. The ozone therapy improved the bleaching effect in the group that received the association of HP.


Resumo O objetivo deste estudo foi avaliar o efeito clareador e físico-químico no esmalte de luz violeta e ozônio, associado ou não ao peróxido de hidrogênio, comparado a 35% de peróxido de hidrogênio. Blocos de esmalte-dentina de molares humanos foram alocados aleatoriamente para receber um dos seguintes protocolos de clareamento (n = 15): (HP) peróxido de hidrogênio a 35%, (VL) luz violeta, (OZ) ozônio, a associação entre peróxido de hidrogênio com ozônio (HP+OZ) ou luz violeta (HP+VL). Todos os protocolos foram realizados em duas sessões, com intervalo de 48 horas entre eles. A cor (espectrofotômetro) e a composição mineral (espectroscopia Raman) do dente foram medidas antes e após os procedimentos de clareamento. As alterações de cor foram calculadas por ΔEab e ΔE00, e o índice de brancura foram calculados. A rugosidade da superfície das amostras clareadas foi medida por microscópio de força atômica. Os dados foram analisados por ANOVA One way ou ANOVA two way de medidas repetidas seguida pelo teste de Tukey (α = 0,05). Os menores valores de alterações de cor (medidos por WI, ΔEab ou ΔE00) foram observados para VL e OZ usados na ausência de HP. VL associada ao HP não foi capaz de melhorar as alterações de cor observadas com o uso do HP, mas a combinação de OZ e HP produz as maiores alterações de cor. Independentemente do protocolo de clareamento, o esmalte clareado apresentou maiores teores de PO4 e CO3 -2 do que os observados inicialmente. Não foi observada diferença significativa entre os protocolos de clareamento testados em relação à rugosidade da superfície do esmalte. É possível concluir que a VL ou o OZ tiveram efeitos reduzidos na mudança de cor do esmalte quando usados sozinhos. A terapia com OZ melhorou o efeito clareador do HP.


Assuntos
Humanos , Ozônio , Clareamento Dental , Clareadores Dentários , Cor , Esmalte Dentário , Peróxido de Hidrogênio
16.
Photobiomodul Photomed Laser Surg ; 39(8): 535-543, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34342514

RESUMO

Objective: The aim of the current study was to use the CIELab system to evaluate the performance of the whitening treatment involving violet light-emitting diode (LED) combined with a home 10% and 22% carbamide peroxide dental bleaching technique on dental enamel. Methods: Fifty blocks of bovine dental enamel were divided into five groups: control group (control), receiving only LED irradiation; Whitening 10%, receiving 10% carbamide peroxide treatment; Whitening 10%+VL, receiving 10% carbamide peroxide treatment combined with LED irradiation; Whitening 22%, receiving 22% carbamide peroxide treatment; and Whitening 22%+VL, receiving 22% carbamide peroxide treatment combined with violet LED irradiation. Color tests were performed before the protocols, after 1 week and after 2 weeks of treatment by using a spectrophotometer and the CIELab parameters: L*, (a*) and (b*). The Whitening 10%, Whitening 10%+VL, Whitening 22% and Whitening 22%+VL groups were submitted to 10% and 22% carbamide peroxide 8 h per day for 14 days, whereas the Control was only stored in artificial saliva. For irradiation in the Control, Whitening 10%+VL, and Whitening 22%+VL groups, we used violet LED at a wavelength of 405-410 nm activated for 60 permanent seconds and 30 sec of pause once per week. As all data exhibited normal distribution, the comparisons were performed by using two-way repeated-measures analysis of variance. A post hoc t-test was employed, followed by the Ryan-Holm stepdown Bonferroni procedure. Results: After 1 week, the Whitening 22%+VL group differed significantly from all other groups in relation to hue, while no difference was found between the remaining groups (p < 0.05). Analyzing lightness, the Whitening 22%+VL and Whiteness10%+VL groups differed from the other groups (p > 0.05). In the 2nd week, the Whitening 22%+VL groups differed significantly from all other groups (p < 0.05) in hue, chroma, and lightness. The comparative analysis of bleaching times within the same group revealed significant differences in the Whitening 22%+VL group between baseline and week 1, baseline and week 2, as well as weeks 1 and 2 in terms of hue (p > 0.05). In the Whitening 22%+VL group, significant differences (p < 0.05) were found between baseline and week 2 as well as between weeks 1 and 2 in chroma (p > 0.05). In the Whitening 22%+VL group, statistically significant differences (p < 0.05) were found between baseline and week 1, baseline and week 2, as well as between weeks 1 and 2 in lightness. In the Whitening 10%+VL group, statistically significant differences (p < 0.05) were found between baseline and week 1, between baseline and week 2, as well as between weeks 1 and 2 in lightness. Conclusions: Tooth whitening treatment involving 10% and 22% carbamide peroxide combined with violet light promoted changes in the three axes of color (ΔH, ΔC, and ΔL) of the specimens evaluated. The use of the gel bleach alone was more efficient when the higher concentration was used. When violet light was combined with the gel, the lower concentration was more efficient.


Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Peróxido de Carbamida , Bovinos , Cor , Clareadores Dentários/farmacologia
17.
J Contemp Dent Pract ; 22(5): 479-483, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-34318764

RESUMO

AIM AND OBJECTIVE: The purpose of this study was to assess the effect of hydrogen peroxide concentration on the bleaching efficacy and penetration through the tooth structure. MATERIALS AND METHODS: One hundred enamel/dentin specimens with cylindrical shape were obtained from bovine incisors. The surfaces were polished and the size standardized. They were divided into five groups (n = 20), following the concentration of hydrogen peroxide in the bleaching gels: 20, 25, 30, 35, and 40% (w/w). The specimens were placed over artificial pulpal chambers containing acetate buffer solution and bleached for 30 minutes (three applications of 10 minutes each). Aliquots of the acetate solution were collected, and the peroxide concentration was measured by an analytic spectrophotometer. The color of the samples was analyzed using a colorimetric spectrophotometer at the baseline and 7 days after the bleaching procedure. The color difference was calculated using the ∆Eab formula. The data were analyzed by one-way ANOVA and Tukey's test (p <0.05). RESULTS: The peroxide concentrations of 20-30% showed smaller bleaching effect than the higher concentrations (p = 0.001). The peroxide penetration was significantly higher (p = 0.001) for the more concentrated gels (35 and 40%). CONCLUSION: The higher peroxide concentrations enhance the bleaching efficacy, but also increased the peroxide penetration through the tooth structure. CLINICAL SIGNIFICANCE: In-office bleaching gels with higher concentrations of hydrogen peroxide (35 and 40%) present superior whitening efficacy. Nevertheless, they might also intensify the negative biological effects on the pulpal tissue, since they exhibit increased penetration potential. How to cite this article: Torres CRG, Zanatta RF, Godoy MMM, et al. Influence of Bleaching Gel Peroxide Concentration on Color and Penetration through the Tooth Structure. J Contemp Dent Pract 2021;22(5):479-483.


Assuntos
Clareadores Dentários , Clareamento Dental , Animais , Bovinos , Cor , Esmalte Dentário , Géis , Peróxido de Hidrogênio , Peróxidos
18.
Arch. health invest ; 10(7)July 2021. ilus
Artigo em Português | BBO - Odontologia | ID: biblio-1343410

RESUMO

Introdução: É crescente a busca por tratamentos estéticos nas clínicas odontológicas, dentre esta demanda, encontra-se soluções reabilitadoras para casos de diastemas e incisivos laterais superiores com morfologia conoide, pois são tidos como fatores antiestéticos. Objetivo: Apresentar uma abordagem interdisciplinar no tratamento de diastemas e unidades dentárias com morfologia conoide. Relato de caso: O paciente procurou atendimento odontológico especializado para reabilitação provisória da estética e função das unidades anterossuperiores durante finalização do tratamento ortodôntico e posteriormente, após conclusão da ortodontia, a reabilitação final. Durante o exame clínico foram observados incisivos laterais superiores com morfologia conoides, ângulo incisal amplo entre os incisivos centrais, ausência de guia canina e diastemas. Após registro fotográfico, foram realizadas as restaurações provisórias. Finalizado o tratamento ortodôntico, o plano de tratamento consistiu na reabilitação através das facetas semidiretas em resina composta. Após moldagem anatômica, enceramento e clareamento dentário, foram realizados os preparos dentários e moldagem funcional, sendo a seguir realizado o ensaio restaurador. Sobre o modelo, foram confeccionadas as facetas em resina composta e realizado o acabamento inicial. Para a fase de cimentação priorizou-se a utilização de condicionamento ácido seletivo para esmalte, cimento fotopolimerizado e uso de polimerizador de alta potência. Após a cimentação foram realizados os ajustes oclusais e acabamento final, com texturização da superfície, seguido pelo polimento. Conclusão: O tratamento realizado evidenciou a importância do tratamento ortodôntico associado a Odontologia Restauradora para o restabelecimento da estética e função, obtendo resultados que melhoraram as relações entre dentes, posicionamento dos lábios, harmonia e equilíbrio dental e facial(AU)


Introduction: There is a growing demand for aesthetic treatments in dental clinics, among this demand, there are rehabilitation solutions for cases of diastemas and upper lateral incisors with conoidmorphology, as they are considered as anti-aesthetic factors. Objective: Present an interdisciplinary approach in the treatment of diastemas and dental units with conoid morphology. Case report: The patient sought specialized dental care for provisional rehabilitation of the aesthetics and function of the anterosuperior units during the finalisation of the orthodontic treatment and later, after completion of orthodontics, the final rehabilitation. During the clinical examination, upper lateral incisors with conoid morphology, wide incisal angle between the central incisors, absence of canine guide and diastemas were observed. After photographic register, provisional restorations were performed. After orthodontic treatment was completed, the treatment plan consisted of rehabilitation through semi-direct facets in composite resin. After anatomical moulding, waxing and tooth whitening, dental preparations and functional mouldingwere performed, hereinafter the restorative test was performed. In this connection,facets were made in composite resin and the initial finishing was carried out. For the cementation phase, priority was given to the use of selective acid conditioning for dental enamel, photopolymerized cement and the use of high-power polymerizer. After cementation, occlusal adjustments and finishing touch were performed with surface texturing, followed by polishing. Conclusion: The treatment performed showed the importance of orthodontic treatment associated with restorative dentistry for the restorationof aesthetics and function, obtaining results that improved the relationship between teeth, positioning of the lips, harmony and dental and facial balance(AU)


Introducción: Crece la búsqueda de tratamientos estéticos en las clínicas dentales, entre esta demanda se encuentran las soluciones rehabilitadoras para casos de diastema e incisivos laterales superiores con morfología conoide, por considerarse factores antiestéticos. Objetivo: Presentar un abordaje interdisciplinario en el tratamiento del diastema y unidades dentales con morfología conoide. Caso clínico: El paciente buscó atención odontológica especializada para la rehabilitación temporal de laestética y función de las unidades anterosuperiores durante la finalización del tratamiento de ortodoncia y posteriormente, trasla finalización de la ortodoncia, la rehabilitación final. Durante el examen clínico se observaron incisivos laterales superiores con morfología conoide, amplio ángulo incisal entre los incisivos centrales, ausencia de guía canina y diastema. Después del registro fotográfico, se realizaron restauraciones provisionales. Una vez finalizado el tratamiento de ortodoncia, el plan detratamiento consistió en la rehabilitación mediante carillas de resina compuesta semidirectas. Después del moldeado anatómico, encerado y blanqueamiento dental, se realizaron las preparaciones dentales y el moldeado funcional, seguido de la prueba restauradora.Sobre el modelo, las carillas se realizaron en resina compuesta y se realizó el acabado inicial. Para la fase de cementación se priorizó el uso de grabado ácido selectivo para esmalte, cemento fotopolimerizable y el uso de un polimerizador de alta potencia. Después de la cementación, se realizaron ajustes oclusales y acabado final, con texturizado de la superficie, seguido de pulido. Conclusión: El tratamiento realizado mostró la importancia del tratamiento de ortodoncia asociado a la odontología restauradora para la restauración de la estética y función, obteniendo resultados que mejoraron la relación entre los dientes, la posición de los labios, la armonía y el equilibrio dental y facial(AU)


Assuntos
Humanos , Masculino , Clareamento Dental , Facetas Dentárias , Estética Dentária , Ortodontia , Cimentação , Resinas Compostas , Ajuste Oclusal , Diastema
19.
J Esthet Restor Dent ; 33(7): 992-998, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34212493

RESUMO

OBJECTIVE: To evaluate the color change stability and patient satisfaction after one-year of at-home bleaching with 10% carbamide peroxide (CP) in trays with or without reservoirs. MATERIALS AND METHODS: Forty-six patients were subjected to bleaching with CP (3 h/daily; 21 days) with a bleaching tray with or without reservoirs. The color was measured one-month and one-year after the completion of bleaching using the spectrophotometer (ΔEab, Δ00 and ΔWi), and shade guide units (ΔSGU). Patients' satisfaction were assessed using a 5-point Likert Scale questionnaire. Data were submitted to paired t-test (α = 0.05). RESULTS: No significant difference between color change after one-month and one-year was observed (VITA Classical shade guide unit and the ΔWi; p > 0.53). Significant differences were observed for the VITA Bleachedguide 3D-MASTER shade guide, ΔEab and ΔE00 (p < 0.03). The level of patient satisfaction was similar between groups (p = 1.00). CONCLUSIONS: Bleaching tray design did not have any influence on the bleaching stability for the 10% CP (Opalescence PF, Ultradent). Patients were very satisfied with the bleaching outcomes regardless of the bleaching tray design. CLINICAL RELEVANCE: Placement of reservoirs in bleaching trays does not increase longevity of dental bleaching. No clinically important color rebound was observed 1 year after bleaching with 10% CP.


Assuntos
Sensibilidade da Dentina , Clareadores Dentários , Clareamento Dental , Seguimentos , Humanos , Peróxido de Hidrogênio , Peróxidos , Resultado do Tratamento , Ureia
20.
J Esthet Restor Dent ; 33(7): 1059-1065, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34228393

RESUMO

OBJECTIVES: To evaluate the tooth whitening efficacy of non-hydrogen peroxide containing mouthrinses. METHODS: Forty incisors were randomly assigned into four groups. Four whitening mouthrinses, Oral-B 3D White Luxe/Procter & Gamble (WL), Listerine Advanced White/Johnson & Johnson (AW), Colgate Max White/Colgate (MW), and iWhite Whitening Mouthwash/Sylphar (iW), were used over a four-week period. Color changes of L*, a*, b*, ΔE*ab , and ΔE00 , were recorded by a digital spectrophotometer (Spectroshade Micro/Mht), at baseline and intermediate week-intervals. Data were statistically analyzed using repeated measures ANOVA at α = 0.05. RESULTS: The first-week mean change of L* was 0.76 and significantly different from the baseline for all solutions, without any further changes. Correspondingly, a* decreased by -0.36, while b* increased by 0.48, contributing to a color change of 1.15 ΔE*ab or 0.91 ΔE00 . No differences were found among the solutions in respect to color-parameter changes (p > 0.05). Differences among time intervals were significant (p < 0.05) and mainly observed between the baseline and the following week-measurements. There was no statistically significant time-solution interaction (p > 0.05). CONCLUSIONS: Non-hydrogen peroxide whitening mouthrinses, slightly contribute to tooth whitening, by removing superficial staining, without any further tooth bleaching effect. CLINICAL SIGNIFICANCE: Non-hydrogen peroxide containing whitening mouthrinses, despite having a quick initial action, reach their ceiling relatively soon. Their effectiveness is barely perceptible and definitely inferior to other professional tooth bleaching methods. Thus, they can only be considered as a supplementary way of keeping teeth whiter, mainly by preventing recurrent tooth discoloration.


Assuntos
Clareadores Dentários , Clareamento Dental , Descoloração de Dente , Dente , Cor , Medicamentos de Ervas Chinesas , Humanos , Peróxido de Hidrogênio , Descoloração de Dente/tratamento farmacológico
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