Effect of coffe and a cola-based soft drink on the color stability of bleached bovine incisors considering the time elapsed after bleaching

There is no consensus about the waiting time necessary for the patient to start consuming beverages containing colorants again after bleaching. Objective: To evaluate the influence of beverages with coloring agents on bleached bovine incisors considering the time elapsed after bleaching. Materials and methods: Sixty bovine incisors were bleached with 35% hydrogen peroxide for in-office use (Whiteness HP Max) and divided into 10 groups. The color was evaluated with a spectrophotometer (Spectro Shade MICRO) before and after bleaching, employing the CIE-Lab system. After bleaching, the teeth were exposed for 5 min to coffee or cola-based soft drink (CBSD) at different periods after bleaching: 10 min, 1 h, 24 h, 48 h, and 72 h. Color (∆E) and lightness (∆L) variations were obtained from the CIE-Lab coordinates. Data were subjected to two-way ANOVA and Tukey HSD tests (

Evaluation of the erosive capacity of children?s beverages on primary teeth enamel : an in vitro study

The consumption of acidified beverages, associated with lower mineralization of primary enamel, is the ideal combination for the development and progression of dental erosion. The objective of this study is to analyze the erosive capacity and the surface roughness of primary teeth enamel after exposure to three different brands of grape juices. Forty enamel blocks of primary teeth were obtained, attened and polished. They were submitted to initial surface roughness analysis (baseline), and randomly assigned into four groups (n = 10): NAT: natural grape juice (Campo Largo); IND: industrialized grape juice (Dell Vale Kapo); SOY: soy-based grape juice (Ades); and CONT (control): artificial saliva. Blocks were immersed for 2 min, 3 times per day, for 9 days. During the whole time of the experiment, the enamel blocks were stored in artificial saliva. After the 9 days, the roughness parameters were determined again. The beverages were analyzed for pH and titratable acidity. Data were statistically analyzed (? = 0.05). The surface roughness did not differ significantly among groups (p > 0.05). However, after the immersion in the different grape juices, the surface roughness values increased significantly (p< 0.05). The pH values were weakly correlated to acidity values; NAT showed the highest titratable acidity values than the other juices (p<0.05). Although the surface roughness values of the experimental groups did not differ from the control group, there was a difference in initial and final roughness in all groups. Grape juices, especially natural, may have an erosive capacity, changing the surface roughness of primary dental enamel

Effect of 2% chlorhexidine treated coronal dentin on bond strength of two self-adhesives cements

Despite advances in adhesive dentistry, lasting bonds between indirect restorations and dentin remain a challenge. Objective: Therefore, the aim of this study was to evaluate the effect of chlorhexidine on the bond strength of self-adhesive cements to dentin after storage for 24 h and 90 days. Material and methods: Forty-eight human third molars crowns were included in polyvinyl chloride matrices using acrylic resin and worn to expose a flat dentin area. The specimens were randomly distributed into 8 groups (n = 12) in accordance with the self-adhesive cement (Rely X U200 and Smart Cem 2), the dentin treatment (application or not of 2 % chlorhexidine digluconate solution for 1 min) and the storage period (24 h or 90 d). Two cylinders’ cements (1.4 x 1 mm) were constructed on the dentin surfaces of each sample, stored in distilled water for 24 h or 90 days and submitted to a micro-shear test. Subsequently, a failure analysis was performed to classify the failure into adhesive, cohesive, and mixed. Data were subjected to ANOVA and Tukey (0.05) tests. Results: There was a statistically significant difference between the materials (Rely X U200 > Smart Cem 2 – p < 0.05) regardless of the surface treatment and the storage period. Conclusion: The chlorhexidine application did not affect the immediate or delayed bond strength values, regardless of the self-adhesive cement

Influence of the conditioning technique of a lithium disilicate vitroceramic

Introduction: Lithium disilicate reinforced glass ceramics are materials that require good adhesion to ensure clinical success. Objective: To evaluate the bond strength of resin cements to lithium-disilicateenhanced vitroceramics using different cleaning techniques of recently conditioned ceramics. Material and methods: Twelve ceramic discs (IPS Empress II) were made and inserted into PVC pipes using acrylic resin. The ceramic surface was designed and submitted to a 10% hydrofluoric acid conditioning process for 20s. Then, the specimenswere divided into 3 groups (n = 16) according to the cleaning techniques of recently conditioned ceramics: 1) control - conventional technique (no cleaning after the conditioning process); 2) application of 37% phosphoric acid for 20s; 3) 90% ethyl alcohol bath in a ultrasound tub for 4 min. After cleaning, the silane agent was applied for 1 minute and silicon matrices (1 mm in diameter x 1 mm in height) were made for further application of the resin cement (Vitique, DMG), which was handled according to the manufacturer’s instructions. Four cylinders were prepared on each ceramic surface. The specimens were storedin distilled water for 48 hours and subjected to the micro-shear test in a universal testing machine. After the micro-shear test, a failure analysis of the specimens was performed. Data were submitted to ANOVA (analysis of variance for a criterion) with a significance level of 5%. Results: There was no significant difference between groups (p > 0.05). Conclusion: the cleaning technique of the recently conditioned ceramics does not interfere with the resin/cement bond strength valuesIntroduction: Lithium disilicate reinforced glass ceramics are materials that require good adhesion to ensure clinical success. Objective: To evaluate the bond strength of resin cements to lithium-disilicateenhanced vitroceramics using different cleaning techniques of recently conditioned ceramics. Material and methods: Twelve ceramic discs (IPS Empress II) were made and inserted into PVC pipes using acrylic resin. The ceramic surface was designed and submitted to a 10% hydrofluoric acid conditioning process for 20s. Then, the specimenswere divided into 3 groups (n = 16) according to the cleaning techniques of recently conditioned ceramics: 1) control - conventional technique (no cleaning after the conditioning process); 2) application of 37% phosphoric acid for 20s; 3) 90% ethyl alcohol bath in a ultrasound tub for 4 min. After cleaning, the silane agent was applied for 1 minute and silicon matrices (1 mm in diameter x 1 mm in height) were made for further application of the resin cement (Vitique, DMG), which was handled according to the manufacturer’s instructions. Four cylinders were prepared on each ceramic surface. The specimens were storedin distilled water for 48 hours and subjected to the micro-shear test in a universal testing machine. After the micro-shear test, a failure analysis of the specimens was performed. Data were submitted to ANOVA (analysis of variance for a criterion) with a significance level of 5%. Results: There was no significant difference between groups (p > 0.05). Conclusion: the cleaning technique of the recently conditioned ceramics does not interfere with the resin/cement bond strength value

The bleaching efficacy of carbamide peroxide gels containing potassium nitrate desensitizer

To evaluate the bleaching efficacy of at-home carbamide peroxide (CP) gels in two concentrations, containing or not a desensitizing agent. Forty incisors were divided into four groups (n=10), according to gel concentrations (10% or 22%), and presence or not of 3% potassium nitrate in the gel. A thin layer of gel was applied to the buccal surface of each tooth for 2h/day for 4 weeks. Bleaching efficacy was measured using a spectrophotometer, and ?E*ab, ?E00 and ?WID were calculated. Measurements were performed at baseline, 7, 14, 21, 28, and 35 days following the first gel application. Data were analyzed by two-way RM-ANOVA and Tukey?s test (?=0.05). Regarding gel concentration or potassium nitrate inclusion, both gels resulted in color change above the perceptibility thresholds, which were similar between gels. Regarding time, significant differences were observed between color change values at 7 days and other time periods. ?WID ranged from 3.8 to 9.6. Significant moderate to strong positive correlation was observed among the parameters. Nor the CP concentration, neither the inclusion of potassium nitrate in the gel, had influence on bleaching efficacy. All gels were effective and showed good results from the first weeks? application

Indications and restorative techniques for glass ionomer cement

Introduction: Due to its chemical, mechanical and biological properties, the glass ionomer cements (GIC) consist in one of the most versatile direct restorative materials, with many potential clinical indications, especially in the context of minimally invasive dentistry. Nevertheless, they have some limitations and require the knowledge of their characteristics and procedures of application in order to achieve their maximum potential. Objective: To demonstrate through literature review the main characteristics, indications, limitations and future perspectives for the use of GIC. Literature review: The database, such as Pubmed and Lilacs were used. Additionally, books were also evaluated and included. Conclusion: The GIC is in constant evolution and is one of the materials that are best suited in the context of preventive and conservative dentistry. It has satisfactory properties and versatility. On the other hand, presents inferior properties when compared to other direct restorative materials, requiring caution during its handling

Esthetic rehabilitation of anterior teeth through gingival recontouring and ceramic veneers: a case report

Esthetic rehabilitations require a broad and thorough evaluation of all the elements that make up the smile such as lips, dental, and periodontal structures to plan the treatment to provide harmony to the whole set. Objective: To demonstrate through a case the association of Periodontics and Restorative Dentistry in the esthetic rehabilitation of anterior teeth replacing resin restorations by modifying the gingival architecture conservatively and harmonically. Case report: It is essential for a multidisciplinary approach to succeed in treatment. The replacement of previous restorations is an increasing demand in currently clinical practice, for many reasons, mainly due to dissatisfaction with the esthetics. It is observed that many of these patients involve not only dissatisfaction with the dental structure but also with the periodontal health, for this reason, it is necessary a previous adaptation of the gingival tissues for proper restorative rehabilitation. Conclusion: Ceramic laminates have proved to be a great choice for anterior teeth restorations, but they must be indicated in specific situations, to obtain excellent results as most conservative as possible.Esthetic rehabilitations require a broad and thorough evaluation of all the elements that make up the smile such as lips, dental, and periodontal structures to plan the treatment to provide harmony to the whole set. Objective: To demonstrate through a case the association of Periodontics and Restorative Dentistry in the esthetic rehabilitation of anterior teeth replacing resin restorations by modifying the gingival architecture conservatively and harmonically. Case report: It is essential for a multidisciplinary approach to succeed in treatment. The replacement of previous restorations is an increasing demand in currently clinical practice, for many reasons, mainly due to dissatisfaction with the esthetics. It is observed that many of these patients involve not only dissatisfaction with the dental structure but also with the periodontal health, for this reason, it is necessary a previous adaptation of the gingival tissues for proper restorative rehabilitation. Conclusion: Ceramic laminates have proved to be a great choice for anterior teeth restorations, but they must be indicated in specific situations, to obtain excellent results as most conservative as possible

Root Preparation of Deciduous Teeth: Efficacy of WaveOne and ProTaper Systems with and without Passive Ultrasonic Irrigation

Introduction: The aim of this study was to compare root preparation of deciduous teeth with WaveOne Large (WO) and ProTaper F4 (PT) instruments with or without passive ultrasonic irrigation (PUI). Methods and Materials: Forty-eight deciduous teeth were scanned before and after root preparation and divided in four groups (n=12): WO+EDTA (WO); WO+EDTA with PUI (WOPUI); PTF+EDTA (PT); and PT+EDTA with PUI (PTPUI). Root canal enlargement by micro-computed tomography and root canal cleaning by scanning electron microscopy (SEM) were analyzed. Data were submitted to two-way ANOVA and Tukey’s tests to analyze the root canal volume variation, and Kruskal-Wallis followed by Friedman and Wilcoxon tests were used to evaluate the cleaning efficacy. The level of significance was set at 0.05. Results: No significant difference occurred in total volume between groups (P&gt;0.05). On analysis by thirds of the root canal, there was a difference in volume between WO (cervical) compared to WO and PT (apical), and PTPUI (middle and apical) (P&lt;0.05). When cleaning of the thirds within the same group was compared, there was a significant difference in all groups (P&lt;0.05). Among the groups, in the thirds, in the cervical a difference occurred (P=0.028), and the pairwise comparisons indicated statistically difference between WO and PT, and WO and PTPUI (P&lt;0.05). In the pairwise comparisons among thirds, in the groups, difrences occured in all of them when compared the cervical and apical thirds (P&lt;0.05). Conclusion: Passive ultrasonic irrigation has not improved the smear layer removal in deciduous teeth. Despite the differences in performance between WO and PT instruments, both were suitable for preparation of deciduous teeth.Keywords: Deciduous Teeth; Endodontic; Passive Ultrasonic Irrigation; Root Canal Preparation; Ultrasoni

Influencia de la vibración sónica y el tipo de cemento en la fuerza de unión de los postes de fibra de vidrio después del envejecimiento.

Introduction: This study evaluated the influence of sonic vibration and thermocycling on the bond strength of fiberglass posts using conventional dual-cured and self-adhesive resin cements. Material and Methods: Ninety-six single-rooted endodontically treated teeth were divided randomly into eight groups according to the cement used (dual-cured or self-adhesive resin cement), use of sonic vibration during post accommodation, and aging conditions (24h in distilled water or 5,000 thermal cycles). The fiberglass posts (White Post DC1, FGM) were cleaned with alcohol, treated with silane and cemented with dual-cured (Allcem Core, FGM) or with self-adhesive resin cement (seT, SDI). For groups in which sonic vibration was used, the posts were accommodated, and sonic vibration was applied for 10 s using a special tip placed on top of the post (Sonic Smart Device, FGM). Pull-out tests were performed after storage in distilled water for 24h at 37°C or after thermocycling (5000 cycles, at 5°C and 55°C). The results were evaluated using three-way ANOVA and Tukey’s test (?=0.05). Results: Significant differences were not observed between the bond strengths of dual-cured (87.93±41.81 N) and self-adhesive cement (82.53±41.43 N). Bond strength for the sonic vibration groups (100.36±42.35 N) was significantly higher than for groups without sonic vibration (70.13±34.90 N). There were significant differences between specimens subjected to thermocycling (98.33±39.42 N) and those stored for 24h in distilled water (72.16±39.67 N). Conclusion: It can be concluded that both sonic vibration and thermocycling significantly improved bond strength of fiberglass posts with the two evaluated resin cements.Introducción: Este estudio evaluó la influencia de la vibración sónica y el termociclado en la fuerza de unión de los postes de fibra de vidrio utilizando cementos de resina autoadhesivos y de curado dual convencionales Material y Métodos: Se dividieron aleatoriamente noventa y seis dientes tratados endodónticamente de raíz única en ocho grupos según el cemento utilizado (cemento de resina de curado dual o autoadhesivo), el uso de vibración sónica durante la acomodación posterior y las condiciones de envejecimiento (24 horas agua destilada o 5.000 ciclos térmicos). Los postes de fibra de vidrio (White Post DC1, FGM) se limpiaron con alcohol, se trataron con silano y se cementaron con cemento de curado dual (Allcem Core, FGM) o con cemento de resina autoadhesivo (seT, SDI). Para los grupos en los que se utilizó vibración sónica, se acomodaron los postes y se aplicó la vibración sónica durante 10 s utilizando una punta especial colocada en la parte superior del poste (Sonic Smart Device, FGM). Las pruebas de extracción se realizaron después del almacenamiento en agua destilada durante 24 horas a 37ºC o después del termociclado (5000 ciclos, a 5ºC y 55ºC). Los resultados se evaluaron mediante ANOVA de tres vías y la prueba de Tukey (? = 0.05). Resultados: No se observaron diferencias significativas entre las resistencias de adhesión del cemento de curado dual (87,93 ± 41,81 N) y el cemento autoadhesivo (82,53 ± 41,43 N). La fuerza de unión para los grupos de vibración sónica (100,36 ± 42,35 N) fue significativamente mayor que para los grupos sin vibración sónica (70,13 ± 34,90 N). Hubo diferencias significativas entre los especímenes sometidos a termociclado (98,33 ± 39,42 N) y los almacenados durante 24 h en agua destilada (72,16 ± 39,67 N). Conclusión: Se puede concluir que tanto la vibración sónica como el termociclado mejoraron significativamente la fuerza de unión de los postes de fibra de vidrio con los dos cementos de resina evaluados