Etch-and-rinse versus self-etch strategy of a universal adhesive in different application methods at the bonding interface of fiber post cementation.

OBJECTIVE: To evaluate the effect of etch-and-rinse (ER) versus self-etch (SE) strategies of a universal adhesive applied with a manual brush (MB) or rotary brush (RB) on the bonding interface of fiber post cementation. METHODS: Forty bovine incisor roots were prepared and divided into four groups according to the methods of application and strategy of universal adhesive use (MB-ER, RB-ER, MB-SE and RB-SE). After 6 months, specimens from different thirds of the post space were evaluated of push-out strength, analysis of adhesive failure patterns, and extent of tags. RESULTS: The RB-ER and RB-SE groups showed the highest bond strength values in the cervical and middle thirds of the post space. Cohesive adhesive failure had the highest incidence in the different thirds of the post space in the ER strategy, regardless of the adhesive application method. The RB-ER group showed the highest tag extensions. CONCLUSIONS: The protocols of universal adhesive application with RB provided the greater bond strength, but only the ER strategy favored the formation of a greater extension of tags at the adhesive interface. CLINICAL SIGNIFICANCE: The application of universal adhesive with RB into the post space increases the strength of the post-cemented fiber bond.

Sealing of restorations with marginal defects does not affect their longevity.

PURPOSE: To evaluate sealed amalgam and resin-based composite restorations after 12 years to determine whether sealing minor defects (micro-repairs) enhanced the longevity of restorations. METHODS: 34 subjects aged 18-80 were recruited. This sample group underwent 137 restorations, including 51 resin-based composite (RC) and 86 amalgam (AM) restorations. Existing restorations with localized, marginal defects were assigned to one of two groups: (a) the Sealing group (n=48, 27 AM; 21 RC) or (b) the Control group (n=89, 59 AM; 30 RC). The quality of each restoration was scored according to the modified USPHS criteria by two examiners at the beginning of the study and after 1-5, 10, and 12 years. Kaplan Meier survival curves were created and a Cox regression was applied to investigate survival variables. Mantel Cox, Wilcoxon, and Friedman tests were performed for comparisons within groups. RESULTS: After 12 years, no statistically significant differences were observed for the variables "restorative material" (P= 0.538) or "sealing yes/no" (P= 0.136) with respect to the longevity of the restorations. All groups behaved similarly with regard to marginal adaptation, secondary caries, and tooth sensitivity (P≥ 0.05). Cumulatively, after a 12-year observation period, sealing minor restoration defects did not affect the longevity of the restorations. CLINICAL SIGNIFICANCE: Sealing minor marginal defects for resin composites or amalgam restorations did not affect their longevity. This intervention may be considered over-treatment for patients with low-to-medium risks for developing dental caries.

Differential Diagnosis and Treatment Proposal for Acute Endodontic Infection.

The objective of this study was to describe the main lesions that simulate clinically and propose a treatment protocol for acute endodontic infection. Signs and clinical symptoms of periodontal abscess, gingival abscess, odontoma, herpes simplex, pericoronitis, acute pulpitis and necrotizing ulcerative gingivitis/periodontitis (NUG/NUP) were described and compared with acute endodontic infections. A treatment protocol was described by optimizing the procedures in access cavity, microbial decontamination and detoxification of the root canal, apical debridement, intracanal and systemic medication and surgical drainage procedures. The convenience of the use of 5.25% sodium hypochlorite, root canal instrumentation using a crown-down technique, intracanal medication with 2% chlorhexidine or triple antibiotic paste and the convenience of the use of antibiotics, analgesics, and surgical drainage to solve cases of acute dentoalveolar abscess was discussed.

Influence of standard load micro- and nanopatterned in surface roughness of bleached teeth and submitted to different surface treatments.

The aim of this study was evaluate the dental enamel after whitening treatment with Opalescence Boost PF™ 38%, correlating the structural alterations in the surface of the enamel with its respective pH and verify if whitened teeth submitted to different finishing and polishing techniques show similar surface texture to healthy teeth (control group). Sixty premolars were divided in 6 groups (n = 10), which had been immersed in artificial saliva during all the experiment. Protocol whitening was performed according to the manufacturer recommendations, and then the specimens were submitted to different polishing technique with Sof-Lex Pop On™ disks, Flex Diamond™ felt disks using two different micrometric polishing pastes (Enamelize™ and Diamond Polish™) and two nanometric polishing pastes (Lummina-E Diamond and Lummina-E Alumina), according to the groups. Representative specimens were analyzed in scanning electronic microscopy (SEM). Whitening gel used in this experiment had modified the morphologic aspect of the enamel surface. It was found that two nanometric polishing pastes (G5 and G6) promoted a less rough surface compared to control group even after the whitening process.

Human dental enamel and dentin structural effects after Er:YAG laser irradiation.

UNLABELLED: Ideally projected to be applied on soft tissues, infrared lasers were improved by restorative dentistry to be used in hard dental tissues cavity preparations--namely enamel and dentin. This paper evidentiates the relevant aspects of infrared Erbium laser's action mechanism and its effects, and characterizes the different effects deriving from the laser's beams emission. The criteria for use and selection of optimal parameters for the correct application of laser systems and influence of supporting factors on the process, such as water amount and its presence in the ablation process, protection exerted by the plasma shielding and structural factors, which are indispensable in dental tissues cavity preparation related to restorative technique, are subordinated to optical modifications caused by the interaction of the energy dissipated by these laser light emission systems in the targeted tissue substrate. CLINICAL RELEVANCE: Differences in the action of infrared Erbium laser system in regard to the nature of the ablation process and variations on the morphological aspects observed in the superficial structure of the target tissue irradiated, may be correlated to the structural optical modifications of the substrate produced by an interaction of the energy propagated by laser systems.

Marginal adaptation of class V restorations with current-generation dentin-bonding agents: effect of different dentin surface treatments.

This study sought to assess the use of chlorhexidine with several excipients as a dentin surface treatment and its effect on marginal adaptation of class V restorations with current-generation dentin bonding agents. A total of 120 human third molars were selected and allocated into 12 groups, with standardized buccal class V restorations randomly divided into preconditioned dentin rinsed with: water; water + chlorhexidine; ethanol; or ethanol + chlorhexidine. After rinsing of dentin (previously conditioned with 35% phosphoric acid) with the test solutions, the Adper single bond 2, prime and bond 2.1, and Excite bonding systems were applied randomly. Restorations were performed with Filtek™ Z350 XT composite resin. The resulting specimens were subjected to thermal and mechanical load cycling. Quantitative analysis of marginal adaptation was performed on epoxy replicas by means of scanning electron microscopy. Results were assessed by means of the Kruskal-Wallis test (percentages of continuous margins) and Wilcoxon test (differences between percentages of continuous margins before and after thermal cycling and mechanical loading), at a significance level of p < 0.05. Outcomes in the chlorhexidine-treated groups were not superior to those obtained with other treatments.

Effect finishing and polishing procedures on the surface roughness of IPS Empress 2 ceramic.

OBJECTIVE: To evaluate the surface roughness of IPS Empress 2 ceramic when treated with different finishing/polishing protocols. MATERIALS AND METHODS: Sixteen specimens of IPS Empress 2 ceramic were made from wax patterns obtained using a stainless steel split mold. The specimens were glazed (Stage 0-S0, control) and divided into two groups. The specimens in Group 1 (G1) were finished/polished with a KG Sorensen diamond point (S1), followed by KG Sorensen siliconized points (S2) and final polishing with diamond polish paste (S3). In Group 2 (G2), the specimens were finished/polished using a Shofu diamond point (S1), as well as Shofu siliconized points (S2) and final polishing was performed using Porcelize paste (S3). After glazing (S0) and following each polishing procedure (S1, S2 or S3), the surface roughness was measured using TALYSURF Series 2. The average surface roughness results were analyzed using ANOVA followed by Tukey post-hoc tests (α = 0.01) RESULTS: All of the polishing procedures yielded higher surface roughness values when compared to the control group (S0). S3 yielded lower surface roughness values when compared to S1 and S2. CONCLUSIONS: The proposed treatments negatively affected the surface roughness of the glazed IPS Empress 2 ceramic.

Degree of conversion of polymer-matrix composite assessed by FTIR analysis.

AIMS AND OBJECTIVES: The behavior of polymer-matrix composite is dependent on the degree of conversion. The aim of this study was to evaluate the degree of conversion of two resin cements following storage at 37°C immediately, 24 and 48 hours, and 7 days after light-curing by FTIR analysis. MATERIALS AND METHODS: The specimens were made in a metallic mold and cured with blue LED with power density of 500 mW/ cm(2) for 30 seconds. The specimens were pulverized, pressed with KBr and analyzed with FTIR following storage times. STATISTICAL ANALYSIS USED: ANOVA (two-way) and Tukey's post hoc. RESULTS: To the polymer-matrix composites between 24 and 48 hours does not show a significant increase (p > 0.05), however, the highest values were found after 7 days. CONCLUSION: The polymer-matrix composites used in this study showed similarity on the degree of conversion and increased of according to the time of storage.

Degree of conversion and hardness of two different systems of the Vitrebond™ glass ionomer cement light cured with blue LED.

This study investigated the physicochemical properties of the new formulation of the glass ionomer cements through hardness test and degree of conversion by infrared spectroscopy (FTIR). Forty specimens (n = 40) were made in a metallic mold (4 mm diameter x 2 mm thickness) with two resin-modified glass ionomer cements, Vitrebond™ and Vitrebond™ Plus (3M/ ESPE). Each specimen was light cured with blue LED with power density of 500 mW/cm(2) during 30 s. Immediately after light curing, 24h, 48h and 7 days the hardness and degree of conversion was determined. The Vickers hardness was performed by the MMT-3 microhardness tester using load of 50 gm force for 30 seconds. For degree of conversion, the specimens were pulverized, pressed with KBr and analyzed with FT-IR (Nexus 470). The statistical analysis of the data by ANOVA showed that the Vitrebond™ and Vitrebond™ Plus were no difference significant between the same storage times (p > 0.05). For degree of conversion, the Vitrebond™ and Vitrebond™ Plus were statistically different in all storage times after light curing. The Vitrebond™ showed higher values than Vitrebond™ Plus (p < 0.05). The performance of Vitrebond™ had greater results for degree of conversion than Vitrebond™ Plus. The correlation between hardness and degree of conversion was no evidence in this study.

Influence of artificial aging in marginal adaptation of mixed class V cavities.

The aim of this study was to investigate whether the artificial aging by thermal cycling had influenced the marginal adaptation of class V restorations with/without chlorhexidine application in the bond process. Twelve intact human third molars were used. Class V cavity preparations were performed on the buccal surface and the teeth received 35% phosphoric acid-etching procedure (Ultradent Products Inc., South Jordan, Utah, USA). Subsequently, the samples were divided in two groups: Untreated acid-etched dentin and chlorhexidine application as an adjunct in the bond process. The adhesive Single Bond 2 (3M ESPE, St. Paul, MN, USA) was used after 2% chlorhexidine application, and the restorations were performed with Filtek™ Z350 XT (3M ESPE) composite resin. The specimens were submitted to artificial aging by thermal cycling with 3,000 cycles. Analyzes were performed on scanning electron microscopy using replicas of marginal adaptation in percentage of continuous margin before and after the artificial aging. The data were analyzed by paired test and the results showed statistically significant differences in the percentage of continuous margin with/without chlorhexidine treatment before and after thermal cycling. This study concluded that the artificial aging by thermal cycling influenced the marginal adaptation of mixed class V composite restorations.

Effectiveness and color stability of non-vital dental bleaching photoactivated by violet LED on blood-stained teeth.

BACKGROUND: Few studies have investigated the effect of violet LED irradiation associated or not with bleaching agents on blood-stained teeth. This in vitro study aimed to evaluate the whitening efficacy and color stability of non-vital dental bleaching using 35% hydrogen peroxide (HP) photoactivated with violet LED (VL) compared to 35% HP alone and 35% HP photoactivated with blue LED (BL). METHODS: Fifty bovine dental crowns were used to obtain specimens of 5 × 5 × 2 mm. After selection based on a previous colorimetric analysis, the specimens were blood-stained and randomly assigned into five groups (n = 10): control (no treatment); 35% HP, 35% HP/BL; 35% HP/VL; and VL. Three bleaching sessions were performed and the colorimetric analysis (∆Eab, ∆L, and ∆WID) was recorded after 7 days, 30 days, and 9 months of the last bleaching session. Two-way repeated measures ANOVA followed by Bonferroni post-hoc test was used at a significance level of 5%. RESULTS: 35% HP, 35% HP/BL, and 35% HP/VL showed higher values of ∆Eab, ∆L, e ∆WID (P < 0.05), without intra- and intergroup differences (P > 0.05). C and VL were similar in all the evaluation times (P > 0.05), showing lower values of ∆Eab, ∆L, and ∆WID (P < 0.05). CONCLUSIONS: 35% HP/VL can be a viable alternative for dental bleaching in endodontically-treated teeth, showing bleaching efficacy similar to 35% HP solely used, even after a 9-month follow-up. VL used alone was not effective to bleach blood-stained teeth.

Effect of non-vital tooth bleaching photoactivated with blue or violet LED on color and microhardness.

BACKGROUND: To evaluate the efficacy of dental bleaching protocols using 35% hydrogen peroxide photoactivated with violet LED on color and microhardness of endodontically treated teeth. METHODS: Forty specimens were selected and randomized into 4 groups (n = 10): C - Control, HP - 35% hydrogen peroxide, HP + BL - 35% hydrogen peroxide + blue LED, HP + VL - 35% hydrogen peroxide + violet LED. Three bleaching sessions were performed for each group. Color analysis was performed 7 days after each bleaching session. Two-way repeated measure ANOVA and Bonferroni test were used to evaluate the effect of different bleaching protocols and evaluation times on the dependent variables (∆E and ∆L). Dentin microhardness was measured 24 h after the third bleaching session. Data were evaluated by ANOVA and Tukey's test at a significance level of 5%. RESULTS: Differences on ∆E and ∆L were verified after the first and second bleaching sessions (p < 0.05) and showed stability after the third one, for all the groups. No differences were observed among HP, HP + BL, and HP + VL groups, regardless of the evaluation time (p > 0.05). HP and C showed the greatest and smallest reduction in dentin microhardness (p < 0.05), respectively. No difference between HP + BL and HP + VL protocols (P > 0.05) was observed. CONCLUSIONS: High concentration hydrogen peroxide (35%) photoactivated with violet LED bleached endodontically treated teeth effectively. However, the same protocol negatively affected the dentin microhardness, but not in the same level of 35% HP solely used.

Fracture strength and hybrid layer formation of endodontically-treated teeth after dental bleaching photoactivated with violet LED.

OBJECTIVE: To evaluate in vitro the effect of dental bleaching using high concentration hydrogen peroxide (HP) photoactivated with violet LED on fracture strength and hybrid layer formation. METHODS: forty endodontically-treated bovine teeth were randomized into four groups (n = 10): C - Control, HP - 35% hydrogen peroxide, HP-BL - 35% hydrogen peroxide photoactivated with blue LED, HP-VL - 35% hydrogen peroxide photoactivated with violet LED. Three bleaching sessions with an interval of 7 days between them were performed. After 10 days of the last bleaching session, the dental crowns were restored and submitted to the fracture strength test. Five specimens from each group were used to evaluate the hybrid layer formation by scanning electron microscope (SEM) images. One-way ANOVA and Kruskal-Wallis test were used for parametric and non-parametric data, respectively. Significance level of 5% was adopted to all the tests. RESULTS: No differences on fracture strength among the groups were observed (p > 0.05). HP and HP-BL showed alterations on hybrid layer formation compared to C group (p < 0.05), but not for HP-VL (p > 0.05). No differences on hybrid layer formation were observed among HP, HP-VL and HP-BL groups (p > 0.05). CONCLUSION: Dental bleaching, photoactivated or not, did not affect the fracture strength of endodontically-treated teeth. Regardless of the protocol used, hydrogen peroxide altered the hybrid layer formation at some level when the restoration was placed after 10 days of the last bleaching session.

Accuracy of digital images in the detection of marginal microleakage: an in vitro study.

PURPOSE: To evaluate the accuracy of Image Tool Software 3.0 (ITS 3.0) to detect marginal microleakage using the stereomicroscope as the validation criterion and ITS 3.0 as the tool under study. MATERIALS AND METHODS: Class V cavities were prepared at the cementoenamel junction of 61 bovine incisors, and 53 halves of them were used. Using the stereomicroscope, microleakage was classified dichotomously: presence or absence. Next, ITS 3.0 was used to obtain measurements of the microleakage, so that 0.75 was taken as the cut-off point, and values equal to or greater than 0.75 indicated its presence, while values between 0.00 and 0.75 indicated its absence. Sensitivity and specificity were calculated by point and given as 95% confidence interval (95% CI). RESULTS: The accuracy of the ITS 3.0 was verified with a sensitivity of 0.95 (95% CI: 0.89 to 1.00) and a specificity of 0.92 (95% CI: 0.84 to 0.99). CONCLUSION: Digital diagnosis of marginal microleakage using ITS 3.0 was sensitive and specific.

New approaches to dental occlusion: a literature update.

Because the study of occlusion is a basic area in dentistry, its components, physiology and integration with the stomatognathic system (SS) have been the subject of interest in the scientific literature. However, the focus given to this issue has changed substantially. Currently, new approaches have been proposed in order to update concepts and to demonstrate the full integration and functionality of this system within the human body. With this approach, the authors proposed the following literature review aimed at gathering recent papers (published from 2000 to 2010) with innovative study design, methodology and/or results. The authors' intention is to show the main trends in the study of occlusion and the SS. The literature review was conducted in the PubMed database, using initially the term "dental occlusion" as a key-word. As items of interest were found, papers were grouped by categories according to their main subject matter. Forty-seven articles were selected and the main categories obtained were: 1. functional magnetic resonance imaging (fMRI); 2. brain activation; 3. masticatory/occlusal function; 4. body function and physical performance; 5. osseoperception; 6. finite element models; and 7. occlusion and pain. Observing the current literature, the authors found that recent studies present different methodologies for the study of occlusion. These studies have allowed scientists to obtain detailed information about the physiology of occlusion and the SS, as well as about its integration in the body. Research in this area should be continued in order to clarify, in detail, the role of each component of the SS and its interaction with human physiology.

Anterior restorations in bleached teeth: difficulty establishing the color after bleaching.

It is becoming more common for patients to look for cosmetic procedures in dental offices. The search for lost or desired esthetics by patients is increasingly frequent and the professional must be able to meet this demand. To do this, dentists not only need to return the tooth back to its normal functioning state but also promote esthetic excellence. In this context, the association of cosmetic procedures, such as teeth whitening and restorative procedures, such as direct adhesive restorations is very common. The composite resins employed nowadays allow the reproduction of various optical properties of natural teeth. With these composite resins, it is possible to reproduce features such as translucency, opacity and specific features of the dental element, to bring back the esthetic harmony of the smile. This article reports a clinical case demonstrating the placement, in a stratified manner, of composite resins in bleached teeth, as well as the reproduction of optical and natural aspects of the teeth. In order to achieve esthetic and functional success of the restored procedure, it is important to be familiar with the new techniques and new materials in the market and above all, we must know when and where to use them.

Using the self-etch adhesives in anterior restoration.

With the arrival of self-etch adhesives systems, there has been a rise in interest among clinicians, making it imperative for health professionals to have knowledge of the properties, characteristics, the association as well as the dental structures of these materials, in order to select them and use them correctly. The self-etch adhesive systems show good values of bond strength, microleakage and performance, and have therefore become an option in direct adhesive restorations. In the regard, this case study aims to describe the technique involving the use of selfetch adhesives system for direct restoration of anterior teeth.

Influence of the internal conditioning of indirect restorations of resin composite in relation to microleakage using LEDs and QTH units.

The current study evaluated in-vitro microleakage of indirect composite inlays fixed with flowable composite and resinous cement and cured by LEDs and QTH units, thus modifying the internal conditioning of the inlays. Thirty-two non-carious teeth were selected and 64 cavity preparations were performed in both enamel and cementum. These teeth were divided into four groups: I--Elipar FreeLight appliance and Filtek Flowable composite; II--Ultralux appliance and Filtek Flowable composite; III--Elipar FreeLight appliance and RelyX cement and IV--Ultralux appliance and RelyX cement. The inlays were internally sandblasted with aluminum oxide, etched with 37% phosphoric acid, washed and silanized. The dental etching was carried out with 37% phosphoric acid for 15 seconds in dentin and 30 seconds in enamel. After being washed and dried, Single Bond dentinal adhesive was then applied, and the inlays were fixed with their respective luting agents, cured in close contact with their surfaces for 60 seconds, thermocycled and immersed in 0.5% basic fuchsine solution. The teeth were then washed and sectioned through the center of the restoration in order for the microleakage readings to be performed using the Image Tool Software. Then, ANOVA and Tukey's statistical tests were applied. In enamel, there was no significant difference for both groups with regard to microleakage; in cementum, the significant difference was 5% (p > 0.005). In agreement with the results, the inlays can be fixed with RelyX and Filtek Flowable resins.

Effects of Photodynamic Therapy on the Adhesive Interface of Fiber Posts Cementation Protocols.

INTRODUCTION: The aim of this study was to evaluate the effects of photodynamic therapy (PDT) on the bond strength and dentinal penetrability of cementation protocols using conventional resin cement (Relyx ARC; 3M ESPE, St Paul, MN) or self-adhesive (Relyx U200, 3M ESPE) after the glass fiber post cementation. METHODS: Forty human canine roots were endodontically treated and prepared for a fiber post. The roots were divided into 4 groups according to the cementation protocol and PDT use: conventional cement (CC), Relyx ARC; self-adhesive cement (SAC), Relyx U200 cement; PDT/CC, PDT + Relyx ARC; and PDT/SAC, PDT + Relyx U200. After cementation of the fiber posts, the roots were cross sectioned, and then specimens from the cervical, middle, and apical thirds of the prosthetic space were obtained. The specimens were submitted to the pushout test and dentinal penetration evaluation of the cementation protocol using laser confocal microscopy. RESULTS: PDT/CC presented the lowest bond strength to root dentin in the cervical third (P < .05). In the middle and apical thirds, all groups presented a similar bond strength (P > .05). PDT/CC presented the lowest dentinal penetration of the adhesive system in the cervical and apical thirds (P < .05). CONCLUSIONS: PDT presented negative effects on the bond strength to dentin in the cervical third after cementation using Relyx ARC and on the dentinal penetrability of the etch-and-rinse adhesive system in the cervical and apical thirds of the prosthetic space.

CLINICAL-THERAPEUTICAL MANAGEMENT OF EXPOSED PULP USING BIOACTIVE MATERIALS: TWO CASE REPORTS

Aims: This article present alternatives of bioactive materials use for direct pulp capping in immature teeth and for apexogenesis.Case report: Two case reports with the application of bioactive cementsare presented here: one in a tooth with pulp exposure and another with deep carious lesion, pulp exposure and open apex.Results: In both cases, the treatment was performed in one visit and a favorable clinical and radiographic follow-up was achieved.Conclusion: The use of bioactive materials ledto the formation of a dentin bridge and healing process in the pulp tissue exposure, without the need for conventional endodontic treatment