Novel Pullulan/Gellan Gum Bilayer Film as a Vehicle for Silibinin-Loaded Nanocapsules in the Topical Treatment of Atopic Dermatitis.

In this study a novel gellan gum/pullulan bilayer film containing silibinin-loaded nanocapsules was developed for topical treatment of atopic dermatitis (AD). The bilayer films were produced by applying a pullulan layer on a gellan gum layer incorporated with silibinin nanocapsules by two-step solvent casting method. The bilayer formation was confirmed by microscopic analysis. In vitro studies showed that pullulan imparts bioadhesitvity for the films and the presence of nanocapsules increased their occlusion factor almost 2-fold. Besides, the nano-based film presented a slow silibinin release and high affinity for cutaneous tissue. Moreover, this film presented high scavenger capacity and non-hemolytic property. In the in vivo study, interestingly, the treatments with vehicle film attenuated the scratching behavior and the ear edema in mice induced by 2,4-dinitrochlorobenzene (DNCB). However, the nano-based film containing silibinin modulated the inflammatory and oxidative parameters in a similar or more pronounced way than silibinin solution and vehicle film, as well as than hydrocortisone, a classical treatment of AD. In conclusion, these data suggest that itself gellan gum/pullulan bilayer film might attenuate the effects induced by DNCB, acting together with silibinin-loaded nanocapsules, which protected the skin from oxidative damage, improving the therapeutic effect in this AD-model.

Clinical behavior of universal adhesives in non-carious cervical lesions: A randomized clinical trial.

OBJECTIVES: This randomized, double-blind clinical trial, , evaluated the behavior of two universal adhesives used in etch-and-rinse (ER) or self-etch (SE) approach in non-carious cervical lesions (NCCLs). METHODS: Two hundred and eleven NCCLs were selected in 54 participants and randomly allocated into four experimental groups: Scotchbond Universal Adhesive - SBU (3M Oral Care) and Prime & Bond Elect - PB (Dentsply Sirona) used in ER and SE modes. Two trained operators placed all resin composite restorations (Filtek Z250, 3M Oral Care). Restorations were evaluated at baseline and after 6 months using both FDI and USPHS modified criteria by a blinded calibrated examiner. Kruskal-Wallis and Mann-Whitney U non-parametric tests were used to compare the restoration failures among experimental groups. RESULTS: Statistically significant differences were found among groups regarding failures (p=0.000 for both FDI and USPHS criteria). PB-SE presented more failures (p<0.05) than other experimental groups. No significant difference was found between any other pair of groups (p>0.05). CONCLUSIONS: The etch and rinse approach affected the clinical performance of Prime and Bond Elect. For this material, the self-etch approach generated lower criteria scores after a six-month follow-up. The bonding strategy did not influence Scotchbond Universal Adhesive clinical performance. (RBR-2GQMVF) CLINICAL SIGNIFICANCE: The clinical behavior of mild universal adhesive Prime & Bond Elect depends on the bonding strategy. The etch-and-rinse approach is recommended for this adhesive system. Scotchbond Universal Adhesive can be used in both bonding strategies without impairing clinical performance.

Self-etch Approach of Universal Adhesives as an Alternative to Minimize Bond Degradation on Sound Dentin vs Caries-affected Dentin over Time.

PURPOSE: To investigate the influence of the etching strategy of universal adhesives on bond degradation to sound and artificially-induced caries-affected dentin. MATERIALS AND METHODS: The universal adhesives (Scotchbond Universal Adhesive; All-Bond Universal; Prime&Bond Elect) and adhesives used as controls (Adper Single Bond 2 and Clearfil SE Bond) were applied to sound and artificially-induced caries-affected bovine dentin. Microtensile bond strength was evaluated immediately (24 h) and after one year of water storage (1 year). Representative specimens were also prepared to assess nanoleakage. Bond strength data (MPa) were analyzed using three-way ANOVA and post-hoc Tukey's test (α = 0.05), considering each substrate separately. RESULTS: Bonding degradation was observed for all universal adhesives on caries-affected dentin, irrespective of the etching strategy. On sound dentin, bonding degradation was observed when adhesives were used on the etch-and-rinse strategy. CONCLUSION: The universal adhesives were not capable of maintaining bond stability over time on caries-affected dentin. The self-etch strategy seems better able to maintain the durability of adhesive interfaces created on sound dentin.

Evaluation of the Use of Potassium Iodide Application on Stained Demineralized Dentin Under Resin Composite Following Silver Diamine Fluoride Application.

Purpose: The purpose of this study was to assess the effect of potassium iodide (KI) after applying silver diamine fluoride (SDF) on the staining of demineralized dentin covered or not by a composite resin layer. Methods: Dentin blocks from 30 bovine incisors were demineralized and randomly allocated in three groups (N equals 10): (1) control (no treatment); (2) treated with SDF; and (3) treated with SDF and KI. Half of the specimens of each group received a composite resin restoration immediately after treatment. A colorimetric evaluation, according to the CIE L*a*b* system, was performed at baseline and after seven, 14, 30, and 60 days. The ΔE data were analyzed using the generalized linear model (Δ equals 0.05). Results: The use of KI immediately after applying SDF decreased the dentin staining at all assessment times. SDF treatment only stained the dentin under composite resin after 60 days. The application of KI reduced the dentin under composite resin staining as ΔE values were similar to the control group even after 60 days. Conclusions: The use of potassium iodide minimizes the darkening of dentin and prevents the staining of the dentin under composite resin restorations in the long-term.

Incorporation of nanocapsules into gellan gum films: A strategy to improve the stability and prolong the cutaneous release of silibinin.

This study aimed to develop gellan gum films containing silibinin-loaded nanocapsules as a novel approach for cutaneous administration of this flavonoid. The nanocapsule suspensions were prepared and presented mean size around 140 nm with homogenous distribution, negative zeta potential and silibinin encapsulation efficiency close to 100%. Then, these suspensions were converted into gellan gum films by solvent casting method. The films were transparent, flexible and maintained the gellan gum hydrophilicity. Nanocapsules provided the silibinin homogenous distribution in the films and prolonged its release, as well as improved the gellan gum occlusion potential. Besides, the nanosuspensions conversion into films improved the silibinin stability. Additionally, the nano-based films presented a swelling index 1.5 times higher than films containing non-nanoencapsulated silibinin. Microscopic analysis evidenced the homogeneous surface of the nano-based films, while films containing non-nanoencapsulated silibinin presented small cracks. The in vitro skin permeation profile confirmed the silibinin gradual release from the nano-based films and its greater retention in the dermis when the skin is damaged. Finally, the formulations presented no irritant effect in the HET-CAM assay. Therefore, the conversion of silibinin-loaded nanocapsule suspensions into films might be considered a promising platform for skin delivery of this flavonoid.

Short-term aging and the dentin bond strength of adhesive systems.

The aim of this study was to compare the effects of 2 aging methods on the dentin bond strength of different adhesive systems, including a universal adhesive. Seventy-two third molars were sectioned to create flat midcoronal dentin surfaces, which were randomly assigned to 12 groups (n = 6 each) according to the aging method (conventional aging, defined as 6 months of water storage; accelerated aging by means of a pH-cycling method; or negative control [immediate bond strength]) and adhesive system (Adper Single Bond 2, Clearfil SE Bond, Prime & Bond 2.1, or Scotchbond Universal). Composite resin blocks were constructed on the flattened dentin surfaces after application of the appropriate adhesive, and the specimens were stored in water for 24 hours. Specimens from the control group were immediately sectioned into resin-dentin sticks (0.8 mm2) and subjected to a microtensile bond strength test. Specimens from the experimental groups were sectioned and tested after undergoing the assigned aging method. Data were analyzed with 2-way analysis of variance and a Tukey test (α = 0.05). The study findings showed that neither aging method significantly affected the dentin bond strength (P = 0.917). Of the 4 adhesives, Adper Single Bond 2 had the highest bond strength value after aging (P < 0.001). Scotchbond Universal adhesive demonstrated statistically significantly higher bond strength values than Clearfil SE Bond and Prime & Bond 2.1, which had statistically similar values. Adhesive failures at the resin-dentin interface or adhesive failures mixed with cohesive failure of the adjacent substrate predominated in all groups. The 2 aging processes did not result in degradation of the adhesive interface or jeopardize the dentin bond strength of any of the adhesives tested.

Bonding of universal adhesive system to enamel surrounding real-life carious cavities.

This study aimed to evaluate the bond strength of a universal adhesive system to enamel surrounding real-life carious cavities. Twenty-eight permanent molars (n = 7) with carious lesions in dentin were subjected to selective carious tissue removal to firm dentin and had their crowns sectioned longitudinally. A universal adhesive system (Single Bond Universal [SBU] used in either etch-and-rinse and self-etch strategies) was compared with an etch-and-rinse Adper Single Bond 2 (ASB) and a self-etch Clearfil SE Bond (CSE) adhesive systems (control systems). Adhesives were applied on the enamel, assumed demineralized, surrounding the cavity margins and on sound enamel (control substrate). Composite cylinders were built (0.72 mm2) and microshear bond strength (µSBS) test was performed after 24 h of water storage. The µSBS values (MPa) were analyzed using two-way ANOVA and Tukey's post hoc tests (α = 0.05). Bond strength values obtained in demineralized enamel surrounding carious cavity margins were significantly lower than that obtained in sound enamel (distant from carious cavity margins) (p = 0.035). The bonding strategy of the SBU did not influenced the bond strength values, which were higher than that obtained with ASB. CSE showed similar µSBS values to ASB and SBU in the self-etch mode. In conclusion, the bond strength to enamel assumed demineralized is lower than to sound enamel. The enamel surrounding carious cavities jeopardize the bonding of universal adhesive system. The bond strength of universal adhesive is similar, regardless to bonding strategy.

Can Endodontic Irrigating Solutions Influence the Bond Strength of Adhesives to Coronal Dental Substrates? A Systematic Review and Meta-Analysis of In Vitro Studies.

PURPOSE: To systematically review the literature to analyze the influence of endodontic irrigating solutions on the bond strength of adhesives to coronal enamel or dentin. MATERIALS AND METHODS: The PubMed/MEDLINE, Web of Science and Scopus electronic databases were used to select laboratory studies related to the research question, without publication year or language limits. From 2461 potentially eligible studies, 2451 were selected for full-text analysis, and 97 were included in the systematic review. Two authors independently selected the studies, extracted the data, and assessed the risk of bias. Pooling bond strength data were calculated using RevMan5.1 with random effects model (α = 0.05), comparing control (no endodontic irrigating solution) and experimental groups (one or more endodontic solutions). RESULTS: No significant difference was found between the control and experimental groups (p = 0.12) in the overall meta-analysis and in the meta-analysis excluding chlorhexidine (p = 0.06). High heterogeneity was found in the meta-analyses. Most included studies in the systematic review were scored as having a high risk of bias. CONCLUSION: The different endodontic irrigating solutions evaluated showed no negative influence on the bond strength of dental adhesives to coronal dental substrates.

Performance of resin composite restorations in the primary dentition: a retrospective university-based study.

BACKGROUND: Limited data is available on variables influencing the survival of composite restorations in primary teeth. AIM: This retrospective university-based study assessed the survival and risk factors associated with failures of resin composite restorations performed in primary teeth. DESIGN: The sample was composed of 961 restorations from records of 337 patients (178 girls and 159 boys) attended in a university dental clinic. The restorations' longevity up to 48 months of follow-up was assessed using the Kaplan-Meier survival test. Multivariate Cox regression analysis with shared frailty was used to evaluate the factors associated with failures (P < 0.05). RESULTS: Mean survival time was 41.5 months (95% CI: 39.7-43.3), with 70.6% of the restorations surviving after 48 months of evaluation. The overall annual failure rate up to 48 months follow-up was 8.3%. Restorations placed in lower arch had lower survival rate than those in upper arch (HR: 1.82, 95% CI: 1.02-3.28). Restorations involving two or more surfaces had more risk of failure than restorations placed in cavities involving only one surface (HR: 2.55 95% CI: 1.34- 4.83). Girls had less risk of failure in their restorations (HR: 0.43, 95% CI: 0.19-0.96). CONCLUSION: Individual and dental variables such as gender, arch type and number of restored surfaces were associated with failure of composite restorations performed in children under daily life clinical environment.

Phosphoric Acid Containing Chlorhexidine Compromises Bonding of Universal Adhesive.

PURPOSE: To examine the influence of phosphoric acid containing chlorhexidine on the dentin bond stability of a universal and a 2-step etch-and-rinse adhesive. MATERIALS AND METHODS: Eighty sound bovine incisors were randomly assigned to 8 groups (n = 10) according to: phosphoric acid (37% phosphoric acid [CTR] or 37% phosphoric acid with 2% chlorhexidine [CHX]); adhesive (Scotchbond Universal Adhesive [SBU]or Adper Single Bond 2 [SB2]); and water storage time (24 h and 6 months). Both acids and adhesives were applied to flat dentin surfaces (following manufacturer's instructions) upon which composite cylinders were built up (0.72 mm2). After storage in distilled water at 37°C for 24 h or 6 months, the composite cylinders were submitted to microshear bond strength (µSBS) testing. Bond strength data (MPa) were analyzed using three-way ANOVA and post-hoc Tukey's test (α = 5%). RESULTS: The interaction among factors was significant (p = 0.012). Both adhesives showed similar 24-h bond strengths regardless of the phosphoric acid. After 6 months, similar values were found for both materials when control phosphoric acid was used, but CHX phosphoric acid produced statistically significantly lower bond strengths for SBU. SB2 bond strength was not affected by acid type. CONCLUSION: Phosphoric acid containing chlorhexidine induced premature bond strength degradation of Scotchbond Universal Adhesive.

Is Adhesive Bond Strength Similar in Primary and Permanent Teeth? A Systematic Review and Meta-analysis.

PURPOSE: To systematically review the literature on laboratory studies to determine whether the bond strength of adhesives to primary teeth is similar to that to permanent teeth. MATERIALS AND METHODS: This systematic review was conducted according to PRISMA and registered in PROSPERO (CRD42014015160). A comprehensive literature search was conducted considering in vitro studies published up to June 2015 in the PubMed/MEDLINE database, with no limit on year of publication. Two reviewers independently selected papers, extracted data and assessed the risk of bias. From 422 eligible studies, 42 were fully analyzed. Thirty-seven studies were ultimately included in the systematic review and meta-analysis. A global comparison was performed with a random-effects model at a significance level of p < 0.05, expressed by the difference of means between the groups. The mean bond strengths and standard deviations were tabulated and statistical analyses were conducted in RevMan 5.1 (The Cochrane Collaboration). RESULTS: There was a significant difference between groups, with permanent teeth presenting higher bond strength than primary teeth (p = 0.0005). When the enamel and dentin substrates were considered separately, dentin presented the same trend (p = 0.002), while for enamel there was no significant difference between the dentitions (p = 0.11). The majority of the studies had a high bias risk. CONCLUSION: Adhesives have higher bond strengths when applied to permanent than to primary teeth. This difference was also valid when the comparison was made between permanent and primary dentin.

Is there a best conventional material for restoring posterior primary teeth? A network meta-analysis.

This study aimed to compare the longevity of different conventional restorative materials placed in posterior primary teeth. This systematic review was conducted following the PRISMA statement and registered in PROSPERO (CRD42016035775). A comprehensive electronic search without date or language restrictions was performed in PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Scopus, Turning Research Into Practice (TRIP) and Clinical Trials databases up to January 2017, selecting randomized clinical trials that assessed the longevity of at least two different conventional restorative materials performed in primary molars. Seventeen studies were included in this systematic review. Pairwise and network meta-analyses were performed and relative risks and 95% confidence intervals (CI) calculated. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. Restorations of primary molars with conventional glass ionomer cement showed increased risk of failure than compomer, resin-modified glass ionomer cement, amalgam, and composite resin. Risk of bias was low in most studies (45.38% of all items across studies). Pediatric dentists should avoid conventional glass ionomer cement for restoring primary molars.

Can Coloured Fluoride Gel Stain Demineralised Enamel?

PURPOSE: This study evaluated the colour changes of demineralized enamel after treatment with coloured fluoride gel. MATERIALS AND METHODS: Enamel blocks obtained from bovine incisors were submitted to artificial caries induction by pH cycling followed by fluoride gel applications (2% sodium fluoride, pH 6.8) using a colourless gel (control group), pink or blue gels. The enamel optical properties were evaluated by spectrophotometry, using the CIE L*a*b* system at baseline (sound enamel), after artificial caries induction (demineralised enamel) and after each of the five fluoride gel applications (weekly intervals). Changes in enamel optical properties (ΔE) were analysed by two-way ANOVA and Tukey's test (α = 0.05). RESULTS: No significant differences were found among fluoride gels (p = 0.476) regardless of the presence of pigments in the gel. ΔE values were significantly different (p < 0.001) between baseline evaluation and treated enamel (after fluoride gel application). CONCLUSION: This in vitro study demonstrated that colour changes in enamel do not occur during fluoride gel treatment, regardless of the presence or absence of coloured pigments in the gel.

Is Caries Associated with Negative Impact on Oral Health-Related Quality of Life of Pre-school Children? A Systematic Review and Meta-Analysis.

Purpose: The purpose of this systematic review and meta-analysis was to assess the impact of dental caries on the oral health-related quality of life (OHRQoL) of preschool children. Methods: A literature search was undertaken through PubMed/MEDLINE, Scopus, and TRIP databases to verify available studies about the topic. Two reviewers independently selected the studies, extracted the data, and assessed the bias risk. Global meta-analysis was carried out comparing means and standard deviations of the OHRQoL overall score from preschool children with and without caries. Subgroup analysis was conducted using different cutoff points for caries: decayed, missing, or filled teeth (dmft) greater than or equal to one and greater than or equal to six. Results: From 597 potentially eligible studies, 63 were selected for full-text analysis and 29 were included in the review: 12 for quantitative analysis and 17 for qualitative analysis. Most studies were conducted in Brazil; Early Childhood Oral Health Impact Scale (ECOHIS) was the instrument used in most studies to evaluate OHRQoL. A dmft index at least of one was sufficient to negatively impact the OHRQoL of preschool children, although a higher cutoff point for caries augmented the difference between groups. Bias risk was low. Conclusions: Caries might be associated with negative impact on the oral health-related quality of life of preschool children, and this association tends to increase as the disease severity worsens.

Is there a best conventional material for restoring posterior primary teeth? A network meta-analysis

Abstract This study aimed to compare the longevity of different conventional restorative materials placed in posterior primary teeth. This systematic review was conducted following the PRISMA statement and registered in PROSPERO (CRD42016035775). A comprehensive electronic search without date or language restrictions was performed in PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, Scopus, Turning Research Into Practice (TRIP) and Clinical Trials databases up to January 2017, selecting randomized clinical trials that assessed the longevity of at least two different conventional restorative materials performed in primary molars. Seventeen studies were included in this systematic review. Pairwise and network meta-analyses were performed and relative risks and 95% confidence intervals (CI) calculated. Two reviewers independently selected the studies, extracted the data, and assessed the risk of bias. Restorations of primary molars with conventional glass ionomer cement showed increased risk of failure than compomer, resin-modified glass ionomer cement, amalgam, and composite resin. Risk of bias was low in most studies (45.38% of all items across studies). Pediatric dentists should avoid conventional glass ionomer cement for restoring primary molars.

Survival and Associated Risk Factors of Resin-based Composite Restorations in Primary Teeth: A Clinical, Retrospective, University-based Study.

PURPOSE: This clinical retrospective study evaluated the survival and risk factors associated with failures of resin-based composite restorations in primary teeth. METHODS: A total of 212 restorations in primary teeth from records of 76 high caries-risk children were included. The restorations' longevity for up to six years of follow-up was assessed using the Kaplan-Meier survival test. Multivariate Cox regression analysis with shared frailty was used to evaluate the factors associated with failures (P<0.05). RESULTS: Mean survival time was 4.3 years (95 percent confidence interval (CI) equals 4.0 to 4.6). The survival of the restorations reached 35.3 percent, up to the sixth year, with an annual failure rate of 18.8 percent. Restorations placed in teeth with pulp treatment had a lower survival rate than those in vital teeth (hazard ratio [HR] equals 2.16, 95 percent CI equals 1.02 to 4.58). Patients who did not use standard fluoride toothpaste had more risk of failure in their restorations (HR equals 6.12, 95 percent CI equals 1.47 to 25.49). CONCLUSIONS: Composite restorations placed in high caries-risk children presented limited survival after six years of follow-up. Standard fluoride toothpaste use was a protection factor, while pulp treatment was a risk factor for restoration failure.

Performance of Universal Adhesive in Primary Molars After Selective Removal of Carious Tissue: An 18-Month Randomized Clinical Trial.

PURPOSE: To evaluate the 18-month clinical performance of a universal adhesive, applied under different adhesion strategies, after selective carious tissue removal in primary molars. METHODS: Forty-four subjects (five to 10 years old) contributed with 90 primary molars presenting moderately deep dentin carious lesions on occlusal or occluso-proximal surfaces, which were randomly assigned following either self-etch or etch-and-rinse protocol of Scotchbond Universal Adhesive (3M ESPE). Resin composite was incrementally inserted for all restorations. Restorations were evaluated at one, six, 12, and 18 months using the modified United States Public Health Service criteria. Survival estimates for restorations' longevity were evaluated using the Kaplan-Meier method. Multivariate Cox regression analysis with shared frailty to assess the factors associated with failures (P<0.05). RESULTS: Estimated survival rates of the restorations were 100 percent, 100 percent, 90.6 percent, and 81.4 percent at one, six, 12, and 18 months, respectively. The adhesion strategy did not influence the restorations' longevity (P=0.06; 72.2 percent and 89.7 percent with etch-and-rinse and self-etch mode, respectively). CONCLUSION: Self-etch and etch-and-rinse strategies did not influence the clinical behavior of universal adhesive used in primary molars after selective carious tissue removal; although there was a tendency for better outcome of the self-etch strategy.

The Bonding Performance of a Universal Adhesive to Artificially-created Caries-affected Dentin.

PURPOSE: To evaluate the bonding performance of a universal adhesive to sound and artificially-created caries-affected dentin, using either the etch-and-rinse or self-etch strategy. MATERIALS AND METHODS: Flat midcoronal dentin surfaces from 48 third molars were randomly assigned to eight groups according to the substrate (sound dentin and artificially-created caries-affected dentin [pH cycling for 14 days]) and the adhesive or application mode (Scotchbond Universal: self-etch or etch-and-rinse strategies; Adper Single Bond 2 and Clearfil SE Bond, a two-step etch-and-rinse adhesive and a two-step self-etch adhesive as controls, respectively). Then, composite blocks were constructed, the specimens were further stored in water for 24 h, and composite-dentin sticks were prepared (0.8 mm2) and tested under tension at 1.0 mm/min. Data were analyzed with two-way ANOVA and Tukey's test (α = 0.05). RESULTS: All adhesives tested on artificially-created caries-affected dentin presented similar µTBS (p > 0.05), and inferior bonding performance when compared to sound dentin (p = 0.000). On sound dentin, Scotchbond Universal presented higher bond strengths when applied in the etch-and-rinse than self-etch mode, but comparable bond strength in each application mode in relation to the respective control adhesive (p = 0.04). CONCLUSION: Scotchbond Universal can be used in different application modes when bonded to artificially-created caries-affected dentin; however, the etch-and-rinse strategy improves its bonding ability to sound dentin. Moreover, Adper Single Bond 2 and Clearfil SE Bond presented similar bond strengths, regardless of the dentin condition and comparable performance in relation to each strategy of Scotchbond Universal.

Does Bonding Approach Influence the Bond Strength of Universal Adhesive to Dentin of Primary Teeth?

OBJECTIVE: To evaluate the effect of bonding strategy on microtensile bond strength (µTBS) of a new universal adhesive system to primary tooth dentin. STUDY DESIGN: Flat dentin surfaces from 25 primary molars were assigned to 5 groups according to the adhesive and bonding approach: Adper Single Bond 2 (two-step etch-and-rinse adhesive) and Clearfil SE Bond (two-step self-etch system), as controls; Scotchbond Universal Adhesive-self-etch, dry or wet-bonding etch-and-rinse strategies. Composite buildups were constructed and the teeth were sectioned to obtain bonded sticks (0.8 mm2) to be tested under tension at 1mm/min. The µTBS means were analyzed by one-way ANOVA and Tukey's tests (α = 0.05). Failure mode was evaluated using a stereomicroscope (400×). RESULTS: Universal adhesive applied following both dry and wet-bonding etch-and-rinse strategies showed similar bond strength compared with control adhesive systems. Self-etch approach resulted in the lowest µTBS values. For all groups, adhesive/mixed failure prevailed. The percentage of premature debonded specimens was higher when the universal adhesive was used as self-etch mode. CONCLUSION: The universal adhesive does not share the same versatility of being used in the etch-and-rinse and self-etch approaches; however, the use of the new adhesive following either wet or dry-bonding may be a suitable option as alternative to two-step etch-and-rinse adhesive protocol.

The Thickness of the Adhesive Layer Increases the Misdiagnosing of the Radiolucent Zones and Restoration Replacement Indication.

OBJECTIVE: To evaluate the influence of the thickness of the adhesive layer and demineralized dentin on the decision to replace composite restoration. MATERIALS AND METHODS: Eighty human third molars with occlusal preparations (Class I) were randomly assigned to eight groups (n = 10): adhesive system (Clearfil SE Bond [CSE] or Scotchbond Universal Adhesive [SBU]); the number of adhesive layers (one or two); and substrate (sound or demineralized dentin). A blinded examiner evaluated radiographs of each restored tooth. Obtained scores for the presence or absence of radiolucent zone under restoration were submitted to a relative risk (RR) calculus and Z-test, and the scores for the decision to replace restorations were submitted to Fisher's exact test (p < 0.05). RESULTS: The relative risk of identifying a radiolucent zone under restoration in sound and demineralized dentin were, respectively, 2 and 1.85 times higher when two layers of adhesive were applied. Demineralized dentin did not increase the probability of identifying a radiolucent zone. A higher relative (1.6, p = 0.01) was observed when two layers of SBU were applied. The number of layers did not influence the relative risk for CSE (RR = 1.3, p = 0.13). CONCLUSION: Thicker layers of SBU increase the relative risk of identifying a radiolucent layer under restoration and the decision to replace a/composite restoration, irrespective of the substrate. The presence of demineralized dentin did not increase the probability of identifying a radiolucent zone when compared to sound dentin. CLINICAL SIGNIFICANCE: The results of this in vitro study suggest that thicker layers of a particular adhesive under resin composite restorations can negatively influence the decision to replace them. (J Esthet Restor Dent 29:193-200, 2017).