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Background: It is still not fully understood what pretreatment is best for achieving maximum tightness for pit and fissure sealings (PFS). Aim: This study investigated microleakage of PFS placed after etching with phosphoric acid or after the application of self‐etching primers/adhesives (SEPA). Design: 131 third molars were assigned to ten groups. In Hel‐P, Helioseal® was applied after phosphoric acid etching. In the other groups, SEPA were used (Dyr‐AP: Adper™ Prompt™ L‐Pop™, Dyract® Seal; Bea: BeautiSealant Primer and Paste; Hel‐Exp: Experimental primer, Helioseal®; Hel‐Cl: Clearfil™ SE Bond1, Helioseal®). Specimens were stored in distilled water at 37°C (28 days), followed by 3500 thermocycles and staining with 5% methylene blue (M) or 5% silver nitrate (S). After methylene blue staining and sectioning, microleakage was assessed light microscopically. During silver nitrate staining, specimens were dissolved by 32% HCl and remaining PFS were evaluated under a SEM. Results: Tightness, percentage of penetrated area, and maximum dye penetration were best for Hel‐P and Hel‐Cl (p < 0.05). Conclusions: Phosphoric acid etching of enamel and Clearfil™ SE Bond resulted in the best sealing quality. Methylene blue staining allowed the evaluation of more criteria (fissure shape, voids, sealant penetration depth) compared to silver nitrate. [ABSTRACT FROM AUTHOR]

Aim: Bacterial micro leakage at implant-abutment interface under functional loading is an important factor, may lead to crestal bone loss and affect the long term success of dental implants. Due to the limited studies about the implant systems with a connection of Slip joint design, this study aimed to evaluate the effect of dynamic loading on bacterial leakage at the implant-abutment interface with slip joint connection. Settings and Design: In vitro-comparative study. Materials and Methods: A total of 20 implants and abutments with slip joint connections (Tapered Screw-Vent, 3.7 mm ×10 mm, Zimmer Dental, USA) was examined and depends on using functional loading were divided into two groups; loaded and unloaded. Initially, 10 µl of Brain Heart Infusion (BHI) culture broth was pipetted to the internal lumen of each implant, then the abutments were tightened to the fixtures and crowns were cemented. In the unloaded group, samples were immersed in E-Coli suspension for 5 days. In the loaded group, samples were immersed in microbial suspension under 500000 cycles using a cyclic load device. Following disconnection of fixtures and abutments, microbial samples were taken from the internal lumen of implants and colonies were counted. Data were analyzed using. Statistical Analysis Used: Mann-Whitney statistical test, SPSS version 24. Results: The mean rate of micro leakage in unloaded and loaded groups was 4000 CFU/ml and 27000 ± 31640 CFU/ml respectively. Bacterial colonies grew in 10% of unloaded samples and 50% of loaded samples. This difference was statistically significant. (P < 0.05). Conclusions: Microbial micro leakage at the implant-abutment interface with slip joint design increased significantly after functional loading. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study was to compare the differences in surface characteristics and roughness of teeth finished for porcelain veneer laminates using different instrumentation and to assess their influence on microleakage. Materials and Methods: Fifty-six extracted human maxillary central incisors were divided randomly into two groups: Group FIsR teeth were finished with a high-speed handpiece with diamond burs; group SO teeth were finished with a sonic oscillating diamond instrument. Porcelain veneers were bonded to 24 teeth in each group. Microleakage was measured in the cervical area. Four remaining teeth in each group were examined using confocal laser-scanning microscopy and scanning electron microscopy. Results: Oscillating instruments produced a rougher dentinal surface (Ra values; P= .029) than those finished with high-speed rotary technology. Conclusions: There is less microleakage when bonded restoration edges are situated over dentin that has been finished with sonic oscillating instrumentation (P= .006). [ABSTRACT FROM AUTHOR]

Removable dentures remain an essential prosthetic consideration in many conditions of oral rehabilitation, especially when restoring edentulous spaces posterior to the anterior remaining teeth. The problems could be attributed to the absence of the posterior abutment, placement of posterior implants provides patients with unique service and benefits not possible with more conventional treatment options. A 44 years old male with Kennedy class I mandibular partially edentulous ridge extending distal to the second premolar, full dentition in maxillary arch, was complaining of poor stability with his old denture .Two implants are placed in the second molar position (one in each side) and received a removable partial denture supported on healing abutments. Patient was followed up for one year clinically. [ABSTRACT FROM AUTHOR]

Summary: Background: Silicone adhesive multilayer foam dressings are used as adjuvant therapy to prevent hospital‐acquired pressure ulcers (PUs). Objectives: To determine whether silicone foam dressings in addition to standard prevention reduce the incidence of PUs of category 2 or worse compared with standard prevention alone. Methods: This was a multicentre, randomized controlled medical device trial conducted in eight Belgian hospitals. At‐risk adult patients were centrally randomized (n = 1633) to study groups based on a 1 : 1 : 1 allocation: experimental groups 1 (n = 542) and 2 (n = 545) – pooled as the treatment group – and the control group (n = 546). The experimental groups received PU prevention according to hospital protocol, and a silicone foam dressing on the relevant body sites. The control group received standard of care. The primary endpoint was the incidence of a new PU of category 2 or worse at the studied body sites. Results: In the intention‐to‐treat population (n = 1605), PUs of category 2 or worse occurred in 4·0% of patients in the treatment group and 6·3% in the control group [relative risk (RR) 0·64, 95% confidence interval (CI) 0·41–0·99, P = 0·04]. Sacral PUs were observed in 2·8% and 4·8% of the patients in the treatment group and the control group, respectively (RR 0·59, 95% CI 0·35–0·98, P = 0·04). Heel PUs occurred in 1·4% and 1·9% of patients in the treatment and control groups, respectively (RR 0·76, 95% CI 0·34–1·68, P = 0·49). Conclusions: Silicone foam dressings reduce the incidence of PUs of category 2 or worse in hospitalized at‐risk patients when used in addition to standard of care. The results show a decrease for the sacrum, but no statistical difference for the heel and trochanter areas. What is already known about this topic?The incidence of hospital‐acquired pressure ulcers (PUs) remains high despite the implementation of best‐practice recommendations.The concept of using silicone foam dressings as an additional prophylactic strategy in PU prevention has been investigated in previous studies but with some limitations.Most RCTs were monocentric studies, restricted to either critically ill or acute care patients and did not observe more than two anatomical at‐risk skin sites, which limited the generalizability of the findings. What does this study add?This large pragmatic RCT suggests that it is beneficial to use silicone adhesive multilayer foam dressings on the sacrum, in addition to standard of care, to help prevent hospital‐acquired PUs.Clinical decision making for heel dressings should be based on the clinical effectiveness of the intervention weighed against the potential risk of falling. Linked Comment: F. Coyer. Br J Dermatol 2021; 185:4–5. [ABSTRACT FROM AUTHOR]

INTRODUCTION: In order to obtain a good prognosis in resin restorations, a strong adhesion not allowing leakage between tooth tissues and restoration should be provided. Effectiveness of universal adhesives on leakage in primary teeth compomer restorations has not been studied. OBJECTIVES: The objective of this study was to evaluate sealing ability of a universal adhesive used with different etching modes after 1- and 3-year of artificial aging in compomer restorations of primary teeth. MATERIAL AND METHODS: Sixty-three extracted mandibular primary second molars were used in the study. Class II box cavities (3 mm × 3 mm × 1.5 mm) were prepared in each tooth. Then, teeth were divided into three groups (n = 21), including total-etch, self-etch, and selective-etch modes. All teeth were restored with compomer (Dyract Extra, Dentsply; Konstanz, Germany) after universal adhesive (Prime & Bond Elect Universal, Denstsply; Milford, USA) application. Teeth were divided into three sub-groups (n = 7) with the following three different aging protocols: 24 h water storage, 1-year aging, and 3-year aging with chewing simulator (Esetron Chewing Simulator; Ankara, Turkey). 50% silver nitrate solution was applied as a tracer, and its' penetration was analyzed in mm3 using micro-computed tomography system (SkyScan 1275; Kontich, Belgium). Data was analyzed with Kruskal-Wallis H and Friedman tests. RESULTS: One-year aging significantly increased the leakage in self-etch group of samples (0.197 ± 0.49 mm3) compared to the total-etch (0.001 ± 0.000 mm3) and selective-etch (0.001 ± 0.000 mm3) groups (p < 0.05). There was no difference between the groups at baseline and after the 3-year artificial aging (p > 0.05). CONCLUSIONS: Self-etch mode of adhesive revealed higher micro-leakage levels at all examination intervals; however, the difference was only significant after the 1-year aging. It can be concluded that universal adhesives can be used with all etching modes in compomer restorations. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Despite the advancements in restorative materials, there are certain drawbacks, including microleakage resulting from insufficient wall adaptation. An effective seal at the tooth/restoration interface is crucial. OBJECTIVES: The aim of the study was to investigate microleakage of different self-adhesive restorative materials. MATERIAL AND METHODS: Class-V cavities were prepared and divided into seven experimental groups with regards to applied material and pre-treatment procedures (n = 12). Cavities were restored with self-adhesive materials, such as hybrid glass ionomer (HGI) without pre-treatment (PT), HGI with PT, glass carbomer (GCP) without PT, GCP with PT, alkasite without adhesive resin (AR), alkasite with AR, nanohybrid composite resin with AR, and compared in terms of microleakage. Data were analyzed using Kolmogorov-Smirnov, Kruskal-Wallis, and Mann-Whitney U tests, with SPSS. RESULTS: Significant difference in microleakage was found among enamel and dentin (p < 0.05). Leakage values from enamel were obtained as follows: alkasite with AR = nanohybrid composite resin with AR < alkasite without AR < HGI with PT < HGI without PT = GCP with PT < GCP without PT, while leakage values obtained from dentin included alkasite with AR = nanohybrid composite resin with AR = alkasite without AR = HGI with PT < HGI without PT = GCP with PT < GCP without PT. CONCLUSIONS: Microleakage properties are material-dependent and may vary due to ingredients. Alkasite with AR could be an alternative to nanohybrid composite due to better sealing ability of both enamel and dentin, while alkasite without AR and HGI with PT are the preferred materials for dentin. GCP without PT showed the highest microleakage. [ABSTRACT FROM AUTHOR]

Background: Flowable composite (FC) is a composite that has low viscosity so that it can flow to the cavity. Selfadhering flowable composite (SAC) is a type of flowable composite which is applied without the stages of etching and bonding because it has an acid monomer. Degradation in the oral cavity such as exposure to acidic fluid and changes in temperature can result in microleakage between the restoration and the cavity wall which can cause secondary caries, and hypersensitivity. Purpose: To prove the difference of microleakage between self-adhering flowable composite (SAC) and flowable composite (FC) after immersed in citric acid. Methods: 28 bovine incisors were cleaned and soaked with 0.01% thymol then divided randomly into 4 groups, groups 1 and 2 are immersed in citric acid with SAC restoration and FC restoration. Groups 3 and 4 are SAC and FC material control groups. All groups were prepared class V with cylindrical shapes. Groups 1 and 2 were treated with thermocycling from 5° and 55°C for 120 cycles and immersed in 3364 ppm citric acid for 24 hours. All groups were immersed in 2% methylene blue for 24 hours, then buccolingual cut for 1 mm. Evaluation of microleakage was seen by the amount of color that entered between the restoration wall and the cavity using a 40x magnification Digital Microscope. Test data analysis using the Kruskal Wallis and Mann Whitney U. Results: Significant differences were found between SAC and FC. Significant differences were also obtained from SAC compared with the SAC control group. Whereas in the comparison between FC and FC control group no differences were found. Conclusion: Microleakage SAC is bigger than FC and SAC control group, but FC has no difference with FC control group. [ABSTRACT FROM AUTHOR]

Rising cancer care costs impose financial burdens on health systems. Applying artificial intelligence to diagnostic algorithms may reduce testing costs and avoid wasteful therapy-related expenditures. To evaluate the financial and clinical impact of incorporating artificial intelligence-based determination of mismatch repair/microsatellite instability status into the first-line metastatic colorectal carcinoma setting, we developed a deterministic model to compare eight testing strategies: A) next-generation sequencing alone, B) high-sensitivity polymerase chain reaction or immunohistochemistry panel alone, C) high-specificity panel alone, D) high-specificity artificial intelligence alone, E) high-sensitivity artificial intelligence followed by next generation sequencing, F) high-specificity artificial intelligence followed by next-generation sequencing, G) high-sensitivity artificial intelligence and high-sensitivity panel, and H) high-sensitivity artificial intelligence and high-specificity panel. We used a hypothetical, nationally representative, population-based sample of individuals receiving first-line treatment for de novo metastatic colorectal cancer (N = 32,549) in the United States. Model inputs were derived from secondary research (peer-reviewed literature and Medicare data). We estimated the population-level diagnostic costs and clinical implications for each testing strategy. The testing strategy that resulted in the greatest project cost savings (including testing and first-line drug cost) compared to next-generation sequencing alone in newly-diagnosed metastatic colorectal cancer was using high-sensitivity artificial intelligence followed by confirmatory high-specificity polymerase chain reaction or immunohistochemistry panel for patients testing negative by artificial intelligence ($400 million, 12.9%). The high-specificity artificial intelligence-only strategy resulted in the most favorable clinical impact, with 97% diagnostic accuracy in guiding genotype-directed treatment and average time to treatment initiation of less than one day. Artificial intelligence has the potential to reduce both time to treatment initiation and costs in the metastatic colorectal cancer setting without meaningfully sacrificing diagnostic accuracy. We expect the artificial intelligence value proposition to improve in coming years, with increasing diagnostic accuracy and decreasing costs of processing power. To extract maximal value from the technology, health systems should evaluate integrating diagnostic histopathologic artificial intelligence into institutional protocols, perhaps in place of other genotyping methodologies. [ABSTRACT FROM AUTHOR]

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Purpose: Provisional restorations exhibit various degrees of microleakage when cemented. Incorporation of quaternized polyethyleneimine nanoparticles (QPEI) into provisional cements may be effective against bacteria in vivo.Materials and Methods: Nine polymethylmethacrylate provisional restorations in human volunteers were evaluated after cementation with and without QPEI nanoparticles. Bacterial load in the provisional cement was assessed after 1 week of cementation.Results: The number of colony-forming units in the cement with QPEI was significantly lower (P < .05) than in the control cement.Conclusion: The results of this in vivo study clearly indicate that provisional cement incorporating QPEI nanoparticles significantly reduces viable bacterial counts in the provisional cement in all patients. [ABSTRACT FROM AUTHOR]

Background: Menstrual cup is one of the menstrual management products that is available throughout the world and can be effective in improving women's quality of life by empowering women in menstrual management. Although menstrual cups have recently entered the Iranian market, the use of this product is limited among women. The aim of this study was to determine the acceptability and safety of menstrual cups among Iranian women.Methods: This is a cross-sectional study conducted in 2020. Iranian women between the ages of 18 and 50 with regular menstrual periods who used the menstrual cup at least for three months were included. Participants were selected through continuous sampling, and they completed a web-based questionnaire including a demographic characteristics form as well as checklists on acceptability and safety through a link sent electronically via social media.Results: The mean score of the overall satisfaction with the cup was 6.54 ± 0.76, and the leakage had the lowest mean score among the satisfaction items (5.25 ± 1.63). About 83% of participants reported experiencing menstrual cup leakage. Among the reported health risks, the highest mean score was for vaginal pain during removal (23.9%). Most participants (83.9%) were familiar with the cup via social networks and 98.6% recommended this product to other women.Conclusions: The high level of acceptability and safety of the menstrual cup showed that this product is a suitable alternative for menstrual management in Iranian women. The results of the study help healthcare providers to learn more about the potential advantages and disadvantages of using cup and create trust in the menstrual cup use based on the results of local evidence-based research. [ABSTRACT FROM AUTHOR]

Background: This study assessed the cost‐effectiveness of atraumatic restorative treatment and the Hall Technique approach (ART/HT) in managing dental caries in young children under the health provider perspective in order to explore a best‐buy alternative to dental general anaesthesia (DGA). Methods: Sixty‐five observations from a randomized controlled trial were used to construct 20 000 microsimulations representing individual‐level clinical outcome and costs of the DGA and ART/HT. Outcome was percentage of successfully managed cases. Costs were reported in 2020 price. Three different scenarios with different assumptions of clinical success of the DGA and the ART/HT were analysed. Probabilistic sensitivity analysis was carried out. Results: The ART/HT successfully managed more cases at lower cost ($557) than the DGA when the system failure of the DGA was considered. Under per protocol analysis, participants in both arms were successfully managed, but the ART/HT costed $580 less than the DGA. Probabilistic sensitivity analysis confirmed the ART/HT was a dominant intervention. Conclusions: The ART/HT approach was non‐inferior in managing dental caries in young children but at lower costs than the DGA. The ART/HT could be a viable option in the provision of comprehensive dental care in locations with limited access to DGA and reduce hospital admission. [ABSTRACT FROM AUTHOR]

First, as has recently been pointed out by Kelleher and Blum8, thought should be given to minimising further tooth destruction [in dentitions already damaged by TW], preserving the remaining sound tooth structure using additive techniques with minimal or no tooth preparation. Figure 2 presents such a case - my first "Dahl" TW case in 1998, in which there was no aesthetic component, merely the need to cover the worn and wearing palatal surfaces of the patient's maxillary incisor teeth. Graph If general dental practitioner readers can remember back to the halcyon (even if we did not think that it was thus at the time!) pre-pandemic times, they will be aware that the incidence of tooth wear (TW) is their patients was increasing, the volume of the problem being confirmed by a 2018 review of having a prevalence globally of 20% to 45%, and erosion in permanent teeth in the UK being between 12% and 100% depending upon which study was cited.1. Secondly, another reason - referral of a patient to another clinic might mean that the patient doesn't return to the practitioner's care. [Extracted from the article]

Purpose: To test the hypothesis that the number of adhesive layers influences the adhesive interface properties under cariogenic challenge conditions using a Streptococcus mutans model. Materials and Methods: Bovine teeth (n = 90) were sectioned into blocks of 5 mm and divided into two groups for microleakage testing (n = 60) and tensile bond strength testing (n = 30). In each group, the samples were subdivided into subgroups according to the number of adhesive layers applied on the dentin: one (SB1), two (SB2), and three adhesive layers (SB3). The samples of the control groups were placed in BHI broth medium supplemented with 2% sucrose without microorganisms, and the experimental groups were submitted to Streptococcus mutans American Type Culture Collection (ATCC) for 5 days. For the tensile strength test, samples were sectioned into 1-mm-thick slices and submitted to a constant load of 0.5 mm/min in a universal testing machine. Fractured surfaces were analyzed and characterized as adhesive, cohesive, or mixed. The microleakage test was performed with silver nitrate solution. Results: In experimental groups, the tensile test revealed a statistically signifcant difference between the one- (18.59 ± 5.3) and three-layer (11.28 ± 5.0) groups (p < 0.001; ANOVA and Tukey's test). The adhesive failure mode was slightly more frequent in the one- (60%) and three-layer (80%) adhesive application groups. On the other hand, the microleakage levels of all experimental groups were statistically similar (Kruskal-Wallis; p > 0.05). Conclusion: The experimental conditions influenced tensile properties and failure modes of different adhesive interfaces; however, they did not influence microleakage. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate microleakage from an antibacterial adhesive and bonding agent added to the fissure sealant on intact enamel. Materials and Methods: One hundred twenty sound third mandibular molars were randomly divided into 6 groups of 20 teeth each. Occlusal pits and fissures were sealed with unfilled sealant material (Clinpro, 3M) after pretreatment with 1. phosphoric acid etching (control); 2. acid etching + Adper Single Bond 2 (SB, 3M); 3. chlorhexidine digluconate (CHX, Ultradent) + acid etching; 4. CHX + acid etching + SB; 5. acid etching + Clearfil Protect Bond (CPB, Kuraray) 6. CPB alone. After 6-month water storage and thermocycling, the specimens were placed in 0.5% fuschin, sectioned and evaluated under a digital microscope. The data were compared between groups with Kruskal-Wallis and Mann-Whitney tests. Results: Differences between groups were statistically significant at P < 0.05. Acid etching alone and with SB showed the lowest microleakage, followed by acid etching + CPB. Chlorhexidine with and without bonding agent showed the greatest microleakage. Conclusion: Conventional acid etching alone or with a one-bottle adhesive were the two most effective methods of reducing microleakage from fissures. Acid etching together with a self-etching adhesive showed better results than self-etching alone. Appling CHX increased microleakage in sealed teeth. [ABSTRACT FROM AUTHOR]

Purpose: To compare marginal microleakage in porcelain veneer restorations following dental finishing using two types of instruments to test the hypothesis that microleakage will be less when teeth are prepared with sonic oscillating burs than when prepared with high-speed rotating burs. Materials and Methods: Fifty-six extracted human maxillary central incisors were selected and divided randomly into two groups. Group 1 samples underwent dental finishing using high-speed rotating diamond burs, while group 2 used sonic oscillating diamond burs. Buccal chamfer preparation was carried out for both groups. Forty- eight of the samples (24 per group) were restored using IPS Empress ceramic veneers. 2% methylene blue was used to evaluate microleakage at the tooth/composite veneer interface. Teeth were sectioned lengthwise into three parts and microleakage was measured at two points -- cervical and incisal -- on each section. Before bonding, four teeth per group underwent SEM examination. Results: Evaluation of microleakage at the cervical dentin margin showed a value of 10.5% in group 1 and 6.6% in group 2, which was statistically significantly different (p < 0.05). Incisal microleakage was 1.3% for group 1 and 1.2% for group 2, which was not significantly different. SEM revealed different patterns of surface texture in both areas according to the instrument used. Group 1 exhibited parallel horizontal abrasion grooves with a milled effect and thick smear layers; group 2 showed abrasive erosion, discontinuous perpendicular depressions, and thin smear layers. Conclusion: Tooth preparations finished with sonic burs produced significantly less microleakage in the cervical dentin area of bonded veneer restorations. No differences were found in the incisal enamel area. [ABSTRACT FROM AUTHOR]

Background: Clinicians routinely provide provisional crowns following teeth preparation. Three-dimensional (3D) printing technology could be used over conventional methods for better fit as lack of adequate fit would result in plaque accumulation, micro-leakage, teeth sensitivity, caries and periodontal diseases.Objective: The aim of the study was to evaluate the marginal and internal fit of provisional crowns fabricated using 3D printing technology and to compare it with that of compression molding and milling methods.Methods: Ninety study models were fabricated by duplicating metal master models of the maxillary first premolar molar with three different finish line chamfer, rounded shoulder and rounded shoulder with bevel. On each study model, provisional crowns were fabricated using compression molding (Mo. group, n= 30 - by over impression technique), milling (Mi. group, n= 30 - by 5-axis dental milling machine), and 3D printing method (3D-P. group, n= 30 - by 3D printer). Marginal and internal fit of the samples were evaluated by measuring gap using a scanning electron microscope with a magnification of 27 ×, at 7 zones A-G on different finish line models. The data were statistically analysed using one-way analysis of variance (ANOVA) at the 0.05 significance level. The p-values were calculated using Dunnett's test.Results: The marginal gap was minimal for the 3D-P. group for each finish line with lowest for rounded shoulder with bevel at zone A 30.6 ± 5.3 and at zone G 32.8 ± 5.4. In axial area, i.e. zones B and F, the minimum gap was noticed for the Mo. group and in Occlusal area (cusp and fossa), for zones C-E maximum gap was determined in Mi. group followed by Mo. and 3D-P. groups.Conclusions: 3D printed provisional crowns have better marginal and internal fit compared to milled and molded provisional crowns. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the bonding of simplified adhesive systems to sound and caries-affected dentin of primary teeth with microtensile (μTBS) and nanoleakage (NL) tests. Materials and Methods: Occlusal cavities were prepared in 36 sound second primary molars. Half of the specimens were submitted to pH cycling to simulate caries-affected dentin. Teeth were randomly restored with one of three materials: the etch-and-rinse adhesive system Adper Single Bond 2 (SB), the two-step self-etching adhesive system Adper SE Plus (SE), and the one-step self-etching adhesive system Adper Easy One (EASY). After storage for 24 h, specimens with cross-sectional areas of 0.8 mm2 were prepared for microtensile testing (1 mm/min). One stick from each tooth was immersed in silver nitrate solution (24 h) and allowed to develop for 8 h in order to score the nanoleakage with SEM. The fracture pattern was evaluated using a stereomicro-scope (400X). The uTBS means were analyzed by two-way ANOVA and Tukey's post-hoc test. For NL, the Kruskal-Wallis and Mann-Whitney tests were used (a < 0.05). Results: SB (35.5 ± 3.5) showed the highest μTBS value to sound dentin, followed by EASY (26.3 ± 1.9) and SE (18.2 ± 6.5) (p < 0.05). No difference among materials was observed for caries-affected dentin (SB: 17.8 ± 4.2; SE: 13.9 ± 3.2; EASY: 14.4 ± 4.2, p > 0.05). For all groups, adhesive/mixed fracture prevailed. Caries-affected dentin promoted silver nitrate uptake into the adhesive interface; however, with SE, the nanoleakage was more pronounced than in the other adhesive systems, even in sound dentin. Conclusion: Caries-affected dentin negatively influences the bond strength and nanoleakage of the two-step etch-and-rinse and one-step self-etching adhesive systems tested in primary teeth. [ABSTRACT FROM AUTHOR]

Purpose: To assess the one-step self-etching adhesive iBond Gluma inside (1-SE) and the two-step etch-andrinse adhesive Gluma Comfort Bond (2-ER), both used in combination with the fine particle hybrid composite Venus, in a laboratory and in a prospective clinical study. Materials and Methods: In the in vitro study, tooth-composite interaction, microleakage, and adhesive failure of 8 Class V restorations per system were evaluated by light and scanning electron microscopy. In the in vivo study, 90 paired Class III/IV restorations were scored over 48 months (modified USPHS criteria). Cumulative failure rates (CFR) were calculated. Results: In vitro, microleakage and adhesive failure at enamel margins were significantly increased with 1-SE in comparison with 2-ER. With 1-SE, micromechanical interlocking at enamel was reduced and pores within the adhesive layer arose. In vivo, after 48 months with 1-SE, decreased marginal integrity and an increased number of dark marginal color lines were observed. Conclusion: Because the results of the 4-year clinical study showed lower esthetics and marginal integrity for the 1-SE adhesive, its use should be viewed critically, which is in line with the reduced enamel-adhesive-composite interaction found in vitro. [ABSTRACT FROM AUTHOR]

Purpose: To examine the bond strength and interfacial nanoleakage expression of fiber posts luted to intraradicular dentin with self-adhesive cements. Six-month and 1-year aging effects were examined. Materials and Methods: Post space was created in endodontically treated human incisors. Each tooth was assigned to a self-adhesive cement/post combination: (1) Bifix SE Cement (Voco) with proprietary posts (Rebilda Post, Voco), (2) RelyX Unicem (3M ESPE) with proprietary posts (Rely X Fiber Post, 3M ESPE), (3) MaxCem (Kerr) with Rebilda Posts. Each specimen was cut into 1-mm-thick sections and either immediately stressed to failure with the push-out bond strength test or aged in artificial saliva for 6 months or 1 year before testing. Additional specimens were processed for quantitative interfacial nanoleakage analysis using ammoniacal silver nitrate. Results: Immediate bond strength ranked in the following order: Bifix SE (7.8 ± 2.9 MPa) = RelyX Unicem (8.4 ± 2.7 MPa) > MaxCem (4.6 ± 2.4 MPa) (p < 0.05). Aging significantly reduced the bond strength of all cements after 1 year: Bifix SE (3.8 ± 1.4 MPa) = RelyX Unicem (5.8 ± 1.7 MPa) > MaxCem (1.3 ± 0.9 MPa; p<0.05). No immediate difference in interfacial nanoleakage expression was found. Nanoleakage increased after aging, and MaxCem showed the highest values. Conclusion: The push-out strength and interfacial nanoleakage expression of fiber posts luted with self-adhesive cements were dependent on luting material and type of post, and were significantly affected by storage time. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the influence of a 2% chlorhexidine solution (CHX) on the bond strength and nanoleakage of two self-etching adhesive systems on demineralized dentin over a 12-month period. Materials and Methods: The middle dentin from sound third molars was exposed and demineralized in vitro. Twelve groups were formed using different adhesive systems (Clearfil Protect Bond [PB], Clearfil SE Bond [SE]) dentin treatment (with or without CHX application), and water-storage times (24 h, 6 and 12 months). Composite resin cylinders were bonded to the prepared dentin, and these specimens underwent microshear bond strength (μSBS) testing and nanoleakage evaluation. μSBS data were submitted to a three-way ANOVA and Tukey's test. The failure mode and nanoleakage were analyzed descriptively by score. Results: There was a statistically significant interaction only between the adhesive system and CHX, and adhesive system and water-storage times. SE showed the lowest μSBS just at 24 h water-storage time regardless of CHX. A significant decrease in μSBS values after 6 months of water storage occurred in all of the groups and was maintained until 12 months. Adhesive failure increased with storage time. All groups showed nanoleakage at the resin/dentin interfaces and an increased silver deposition was noticed after 6 and 12 months of water storage. The highest percentages of nanoleakage were found in CHX groups. Conclusion: CHX did not interfere with µSBS values for either self-etching adhesive system, but water storage did. Bond strength decreased for both adhesive systems after 6 and 12 months, regardless of CHX application. Nanoleakage increased with water-storage time and with CHX application. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate a new method of simulated pulpal pressure in vitro in comparison with the conventional one. Materials and Methods: Four adhesives were analyzed: a three-step etch-and-rinse (Scotchbond Multi-Purpose [SBMP]), a two-step etch-and-rinse (Single Bond 2 [SB]), a two-step self-etching (Clearfil SE Bond [SE]), and a one-step self-etching (Clearfil S3 [S3]) system. Restorations were built up in flat, deep dentin from extracted molars. After two methods of simulated pulpal pressure or no pulpal pressure (control groups), the samples were cut into sticks and submitted to microtensile bond strength (µTBS) testing and nanoleakage evaluation. Results were analyzed with two-way ANOVA and Tukey's test (p < 0.05). Results: In general, statistical analysis of µTBS showed SBMP>SB=SE>S3. For both methods of simulated pulpal pressure, the µTBS of SB and S3 was lower than in control groups. For SBMP and SE, the µTBS remained stable with simulated pulpal pressure. Conventional and experimental methods of simulating pulpal pressure resulted in similar µTBS (p = 1.00) and nanoleakage patterns. Silver impregnation was higher with SB and S3, especially after simulated pulpal pressure with both methods. Conclusion: The experimental simulated pulpal-pressure method tested here was similar to the conventional method and can be an alternative to it. The simplified adhesives show reduction in bond strength after simulated pulpal pressure. The multistep adhesives have stable bond strengths under simulated pulpal pressure. Therefore, the separate application of hydrophobic resin can achieve resistance to bonding deterioration after hydrostatic pressure. [ABSTRACT FROM AUTHOR]

Purpose: 1) To evaluate the marginal sealing efficacy of Biodentine at the cervical margins of approximal cavities placed in molars; 2) to evaluate and compare the use of Biodentine in combination with resin-based adhesives and a resin composite, compared with a resin-modified glass-ionomer cement (Fuji II LC). Materials and Methods: Sixty approximal cavities were prepared on mesial and distal surfaces of 30 extracted human third molars. The teeth were randomly assigned into 6 groups of 10 cavities each: (G1) Biodentine, (G2) Fuji II LC as a filling material, (G3) Biodentine as a base + Optibond Solo Plus + silane + Filtek Z250, (G4) as in G3 without silane, (G5) Biodentine as a base + Septobond SE + Filtek Z250, (G6) Fuji II LC as a base + Optibond Solo Plus + Filtek Z250. The materials were applied according to the manufacturers' instructions. Biodentine required no dentin or enamel surface conditioning treatment. The teeth were thermocycled 2500x (5ºC to 55ºC). The specimens were then sealed with a 1-mm window around the marginal interface. Samples were immersed in a 50% w/v silver nitrate solution and exposed to a photodeveloping solution. The teeth were embedded in resin (Sody 33) and sectioned through the restorations. The silver penetration was directly measured using a light microscope. The results were expressed as ordinal scores from 0 to 3 at cervical, interfacial, and enamel margins. The data were analyzed with the nonparametric Kruskal-Wallis, Games Howell, and Wilcoxon signed rank tests (p < 0.05). Results: No statistically significant differences were found between the 6 groups, neither for the dentin cervical margins nor for cervical lining (Biodentine or Fuji II LC)/resin composite interfaces. Statistically significant differences were observed between G5 (median score = 2.0) and the other groups (median score = 1.0) for the enamel margins. Statistically significant differences were found between enamel and dentin cervical margins in G2 (enamel median score = 1.0; dentin median score = 1.5) and G5 (enamel median score = 2.0; dentin median score = 1.0). Conclusion: Within the limits of this in vitro study, Biodentine as dentin substitute in cervical lining restorations or as a restorative material in approximal cavities when the cervical extent is under the CEJ seems to perform well without any conditioning treatment. However, the operating time is longer than when a RMGIC (Fuji II LC) is used. [ABSTRACT FROM AUTHOR]

Aim: This study is aimed to evaluate the impact of three irrigating solutions on the apical sealing ability of three endodontic sealers. Materials and Methods: One hundred maxillary central incisors were decoronated, and their roots were assigned into three experimental groups (n = 30 each) according to the nature of the irrigating solution and two control groups (n = 5 each). Each experimental group was divided equally into three subgroups (n = 10 each) according to the type of root canal sealer. All root canals were instrumented using ProTaper Universal rotary system and irrigated with 3% sodium hypochlorite (NaOCl/Group 1), 3% hydrogen peroxide (H2O2/Group 2), and 2% chlorhexidine gluconate (CHX/Group 3). The final irrigating solutions for all groups were 17% ethylenediaminetetraacetic acid (EDTA) and distilled water. The continuous-wave technique was used to fill the prepared canals with the following materials: MTA-Fillapex/Gutta-percha (Subgroup A), AH Plus/Gutta-percha (Subgroup B), and Realseal SE/Realseal (Subgroup C). The microleakage was assessed after 72 hours using the linear dye penetration method. The results were statistically analyzed with one-way analysis of variance. Results: Significant differences were found only between the experimental groups (P < 0.05). All root canal sealers after irrigation with 3% H2O2 showed the lowest amount of leakage. The highest apical leakage was observed when 3% NaOCl and 2% CHX were used. Conclusions: The type of irrigating solution could affect the apical sealing ability of experimental sealers used with the continuous-wave obturation technique. Root canal irrigation with 3% H2O2 +17% EDTA increased the apical sealing ability of all root canal sealers. Root canal irrigation with 3% NaOCl or 2% CHX +17% EDTA decreased the apical sealing ability of all root canal sealers. [ABSTRACT FROM AUTHOR]

Introduction: The removal of collagen by chemical methods can effectively decrease the marginal microleakage of composites used in restorative dentistry. Objectives: To present research focused on the assessment of the impact of surface treatment of dentin with 5% bromelain and 5% trypsin on the microleakage of composites. To present research focused on the assessment of the impact of surface treatment of dentin with 5% bromelain and 5% trypsin on the microleakage of composites. Material and methods: In the lingual and buccal surfaces of 60 extracted premolars, class V cavities were prepared in standard condition. The test cases were divided into three groups (n = 40). In the control group, 37% phosphoric acid was employed for etching the cavities. In one of the groups, Adper Single Bond was utilised in the wall of cavity, while OptiBond Solo was applied in the other group. Afterwards, the samples were restored by employing Z250 composite. 5% bromelain and 5% trypsin were used in the test groups. The samples were then immersed in 2% fuchsine solution to analyse the marginal microleakage. Results: No significant difference was observed in the occlusal marginal microleakage of study groups (p = 0.43), but the difference in microleakage of cervical margins was significant (p = 0.000). Conclusions: Pretreatment of cavity by using 5% bromelain in the etched dentin surface showed no significant impact on microleakage. However, using 5% trypsin after etching has a negative effect on the microleakage at the cervical margins. [ABSTRACT FROM AUTHOR]

INTRODUCTION: Dental restorative treatments are the most prevalent procedure in dental clinics. Multiple clinical steps are entailed in these treatments especially when using risen composites, which require a properly long chair-time. Bulk-fill composites may be reliable restorative materials for saving time and cooperative behavior with pediatric patients. OBJECTIVES: The aim of this research was to assess a laboratory comparison of the marginal microleakage of bulkfill and conventional composites in primary molars' class II cavities. MATERIAL AND METHODS: Forty-eight standardized class II cavities were prepared in primary molars and divided into three groups (n = 16). Group 1 was restored by conventional composite (Arabesk-Voco) applied via one bulk technique. Group 2 was restored by bulk-fill composite (X-tra fil-Voco) applied also through one bulk technique. Group 3 was incrementally restored by conventional composite (Arabesk-Voco). Phosphoric acid with 37% concentration and bonding agent (Solo bond M-Voco) were used in all specimens. Teeth were sectioned mesiodistally, after having been subjected to 1,500 water cycles and immersed into 0.5% methylene blue to evaluate dye penetration by a four-degree scale. Data was collected and analyzed by SPSS V24. RESULTS: The three groups did not show complete prevention of dye penetration on the gingival or occlusal margins. No significant difference was observed in terms of dye penetration between the three groups on the gingival margins (p = 0.534). Greater occlusal microleakage in the conventional incremental composite group than X-tra fil bulk-fill group was observed. The comparison between the gingival and occlusal margins in each group showed higher leakage on the gingival margins in the bulk filling groups 1 and 2. CONCLUSIONS: There was no significant difference among the groups in terms of gingival microleakage in small class-II cavities in the primary molars. In fact, the application of composite restoration in thin layers on the occlusal section increased the microleakage. [ABSTRACT FROM AUTHOR]

Background: Data from countries that have implemented a complete phase out of dental amalgam following the Minamata agreement suggest increased costs and time related to the placement of alternatives with consumers absorbing the additional costs. This aim of this study was to investigate the impact of a complete phase out of dental amalgam on oral health inequalities in particular for countries dependent on state run oral health services.Methods: A mixed methods component design quantitative and qualitative study in the United Kingdom. The quantitative study involved acquisition and analysis of datasets from NHS Scotland to compare trends in placement of dental amalgam and a survey of GDPs in Yorkshire, UK. The qualitative study involved analysis of the free text of the survey and a supplementary secondary analysis of semi-structured interviews and focus groups with GDPs (private and NHS), dental school teaching leads and NHS dental commissioners to understand the impact of amalgam phase down on oral health inequalities.Results: Time-trends for amalgam placement showed that there was a significant (p < 0.05) reduction in amalgam use compared with composites and glass ionomers. However dental amalgam still represented a large proportion (42%) of the restorations (circa 1.8 million) placed in the 2016-2017 financial year. Survey respondents suggest that direct impacts of a phase down were related to increased costs and time to place alternative restorations and reduced quality of care. This in turn would lead to increased tooth extractions, reduced access to care and privatisation of dental services with the greatest impact on deprived populations.Conclusion: Amalgam is still a widely placed material in state run oral health services. The complete phase down of dental amalgam poses a threat to such services and threatens to widen oral health inequalities. Our data suggest that a complete phase out is not currently feasible unless appropriate measures are in place to ensure cheaper, long-lasting and easy to use alternatives are available and can be readily adopted by primary care oral health providers. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this literature review was to investigate the results from in vitro laboratory studies on the influence of temperature and relative humidity present before polymerization on enamel and dentin bonding systems. Materials and Methods: A systematic search was carried out including articles published in English, in peer-reviewed journals, and indexed in MEDLINE/PubMed database. The search was carried out using the terms: relative AND humidity AND dental. In vitro studies were retrieved and divided into laboratory simulation studies and studies on physical properties. Laboratory simulation studies were addressed by subtopic: resin-enamel bond strength, resin-dentin bond strength, and dentin-enamel microleakage. Studies on physical properties tested the influence of humidity and temperature through polymerization contraction, flexural strength, and dentin wettability. Results: Laboratory simulation studies demonstrated a strong influence of humidity and temperature on dentin and enamel bond strength and microleakage with dental adhesives systems. The studies on physical properties failed to demonstrate any influence of humidity on the adhesion performance, except for wettability measurement. Conclusion: The clinical relevance of these in vitro results remains to be demonstrated. A review of in vivo clinical studies will complete the literature data presented here. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the ability of the provisional filling material Cavit-W alone or in combination with different restorative materials to prevent bacterial leakage through simulated access cavities in a resin buildup material. Materials and Methods: LuxaCore resin cylinders were subdivided into 4 experimental groups (n = 30), plus a positive (n = 5) and a negative (n = 30) control group. One bore hole was drilled through each cylinder, except those in the negative control group (G1). The holes were filled with Cavit-W (G2), Cavit-W and Ketac-Molar (glass- ionomer cement, G3), Cavit-W and LuxaCore bonded with LuxaBond (G4), Cavit-W and LuxaCore (G5), or left empty (G6). Specimens were mounted in a two-chamber leakage setup. The upper chamber was inoculated with E. faecalis. An enterococci-selective broth was used in the lower chamber. Leakage was assessed for 60 days and compared using Fisher's exact test ( < 0.05) corrected for multiple testing. Results: Bacteria penetrated specimens in the positive control group within 24 h. All specimens in the negative control group resisted bacterial leakage for 60 days. Twenty-seven specimens in G2, 26 in G3, and 16 specimens in G5 showed bacterial leakage by the end of the experiment. G4 prevented bacterial penetration completely. The statistical comparison revealed significant differences between G4 and all other experimental groups. Conclusion: Under the current conditions, Cavit-W alone or combined with a glass-ionomer cement did not prevent bacterial leakage through a resin buildup material for two months. In contrast, covering Cavit-W with a bonded resin material resulted in a bacteria-tight seal for two months. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Purpose: This study evaluated the effects of peripheral enamel margins on the long-term bond strength (µTBS) and nanoleakage in resin/dentin interfaces produced by self-adhesive and conventional resin cements. Materials and Methods: Five self-adhesive [RelyX-Unicem (UN), RelyX-U100 (UC), GCem (GC), Maxcem (MC), Set (SET)] and 2 conventional resin cements [RelyX-ARC(RX), Panavia F(PF)] were used. An additional group included the use of a two-step self-etching adhesive (SE Bond) with Panavia F (PS). One hundred ninety-two molars were assigned to 8 groups according to luting material. Five-mm-thick composite disks were cemented and assigned to 3 subgroups according to water-exposure condition (n = 6): 24-h peripheral exposure (24h-PE-enamel margins), or 1 year of peripheral (1yr-PE) or direct exposure (1yr-DE-dentin margin). Restored teeth were sectioned into beams and tested in tension at 1 mm/min. Data were analyzed by two-way ANOVA and Tukey's test. Two additional specimens in each group were prepared for nanoleakage evaluation. Nanoleakage patterns were observed under SEM/TEM. Results: Except for RX, no significant reduction in µTBS was observed between 24h-PE and 1yr-PE. 1yr-DE reduced µTBS for RX, PF, GC, MC, and SET. No significant reduction in µTBS was observed for PS, UC, and UN after 1 year. After 1yr-DE, RX and PS presented the highest µTBS, and SET and MC the lowest. Nanoleakage was reduced when there was a peripheral enamel margin. SET and MC presented more silver deposition than other groups. Conclusion: The presence of a peripheral enamel margin reduced the degradation rate in resin/dentin interfaces for most materials. The µTBS values produced by the multi-step luting agents RX and PS were significantly higher than those observed for self-adhesive cement [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the effects of increasing thermocycling regimens on bond strength and nanoleakage of an etch-and-rinse adhesive. Materials and Methods: Adper Single Bond (3M ESPE) was used for bonding resin composite to human enamel and dentin. Specimens were stored in water (37°C, 24 h) and subjected to thermocycling (5°C and 55°C) in five groups: 1. control (no thermal cycling), 2. 100, 3. 500, 4. 2000, or 5. 10,000 cycles. The microshear bond test was performed at a crosshead speed of 1 mm/min (n = 16). Nanoleakage specimens were immersed in silver nitrate and FE-SEM micrographs were digitally analyzed to calculate silver penetration in three samples. Results: The mean bond strength to enamel was not significantly affected by thermocycling. However, artificial aging decreased dentin bond strength in groups 4 and 5 compared to control. Weibull analysis indicated that the characteristic strength decreased gradually with aging in both substrates. All groups exhibited some nanoleakage, and a significant increase in silver penetration compared to the control was observed in enamel and dentin groups 2 to 5. Conclusion: A nanoleakage increase was detected in an earlier stage of aging than when a significant drop in bond strength was observed, with the dentin bond being more susceptible to deterioration. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this clinical study was to investigate the influence of salivary exposure on microtensile bond strength of one self-etching adhesive resin. Materials and Methods: Thirty carious premolars were divided into two groups: a rubber-dam was either inserted before or after cavity preparation and the cavities were restored using direct composite resin. After extraction, the teeth were sectioned into microbars and the microtensile bond strength (MTBS) test was conducted (α = 0.05). Scanning electron microscopy (SEM) and silver nitrate staining to detect nanoleakage were conducted to evaluate the sealing quality of the bonded interface. Results: Statistical analysis revealed that placement of rubber-dam before cavity preparation resulted in significantly higher MTBS values (24 ± 2 MPa) and predominantly cohesive failures (85%). SEM of specimens exposed to saliva revealed the presence of structural defects at the tooth/resin interface and pull-out of shorter resin tags. Silver nitrate nanoleakage confirmed these findings as well. Conclusion: It is recommended to insert a rubber-dam before commencing with cavity preparation in order to ensure strong and durable bond strength. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate interface degradation leading to marginal microleakeage in Class II restorations that had received an application of surface sealant at the tooth/restoration interface or not. Materials and Methods: Eighty bovine incisors were used, and the teeth were split obliquely, 10 mm from the amelodentinal proximal junction, and finished with water abrasive papers to obtain a smooth, flat incisal surface. Cavities were made to simulate Class II preparations (8 mm high, 4 mm wide and 1.5 mm deep), and the restorations were performed with a composite resin. Teeth were then randomly allocated into 8 groups according to the surface sealant (none, Fortify, Single Bond 2, or Scothbond MP Plus) and aging process (none or thermocycling and storage for 6 months). Microleakage was then evaluated using a dye penetration method immediately after the restoration or after aging. The samples were triturated and assessed by spectrophotometer. Results: Microleakage was statistically similar in all groups when assessed immediately after the restorative procedure. After aging, teeth sealed with Fortify presented better results than the other groups. Conclusion: Aging causes interface degradation and increased microleakage. Surface sealant can reduce these effects and decrease microleakage in Class II restorations. [ABSTRACT FROM AUTHOR]

Purpose: To investigate the depth of nanoleakage of four luting agents for bonding fiber posts after thermomechanical fatigue. Materials and Methods: Twenty-four extracted human anterior teeth were endodontically treated, sectioned at the cementoenamel junction, and restored with fiber posts using four commercially available resin cements with the corresponding core buildup materials (n = 6): Panavia F 2.0/Clearfil DC Core Automix (Kuraray), Variolink II/Multicore Flow (Ivoclar Vivadent), RelyX Unicem/Filtek Z250 (3M ESPE), and Multilink Sprint/Multicore Flow (Ivoclar Vivadent). The specimens received all-ceramic crowns and were subjected to thermomechanical fatigue (1.2 million cycles). After cutting off the crowns, the roots were isolated with nail polish except for a 1-mm rim around the root canal, and immersed in 50 wt% ammoniacal silver nitrate solution for 24 h. The specimens were sectioned perpendicular to the long axis of the tooth into four slices, fixed, dehydrated, and processed for FE-SEM. Leakage was analyzed using backscattered FE-SEM and EDS. Results: The depth of nanoleakage was significantly affected by the factor resin cement (p < 0.015; Kruskall-Wallis). Multilink Sprint resulted in significantly deeper penetration of silver particles than the other materials (p < 0.05; Mann Whitney U-Test). Conclusion: Hybridization of the root canal dentin created by self-etching or etch-and-rinse adhesive systems demonstrated distinctive nanoleakage up to 0.8 mm, whereas the self-adhesive resin cement RelyX Unicem was able to prevent distinctive leakage at this penetration depth. However, none of the investigated luting systems would be able to hermetically seal the root canal if leakage occurred around the margins of the coronal restoration. [ABSTRACT FROM AUTHOR]

With the introduction of the Er:YAG laser, it has become possible to remove enamel and dentin more effectively and efficiently than with other lasers. Thermal damage is reduced, especially in conjunction with water spray. Since FDA (Federal Drug Administration) approval of the Er:YAG laser in 1997 — for caries removal, cavity preparation and conditioning of tooth substance — there have been many reports on the use of this technique in combination with composite resins. Moreover, cavity pretreatment with Er:YAG laser (laser etching) has been proposed as an alternative to acid etching of enamel and dentin. Reports evaluating the adhesion of glass-ionomer cements to Er:YAG-lased tooth substance are scarce. This article reviews the literature regarding adhesion and sealing efficacy using different (pre)treatment protocols in association with Er:YAG laser preparation. Recent research has shown that lasing of enamel and dentin may result in surface and subsurface alterations that have negative effects on both adhesion and seal. It is concluded that at present, it is advisable to respect the conventional pretreatment procedures as needed for the respective adhesive materials. Although the majority of present day reports show that microleakage and bond strength are negatively influenced by laser (pre)treatment (compared with conventional preparation), there is ongoing discussion of how adhesion is best achieved on Er:YAG-lased surfaces. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the effect of adhesive agents and fissure morphology on the microleakage and penetrability of pit and fissure sealants. Method and Materials: Sealants used in this study included Aegis (Bosworth), conseal f (Southern Dental Industries), and Admira Seal (Voco). Adhesive agents included Optibond Solo Plus (sds/Kerr) and Clearfil S³Bond (Kuraray). Ninety extracted permanent molars were randomly assigned to 9 groups combining sealant and adhesive agent materials. A sealant and control group (phosphoric acid etch only) was also included. Dye penetration (microleakage), penetrability, and fissure morphology assessment was performed for the treatment groups through microscopic evaluation. Results: Significant (P = .003) differences in microleakage were exhibited, with the Aegis + control and Aegis + Optibond Solo Plus groups displaying less leakage, while significant (P = .03) differences were also noted between groups regarding penetrability. Fissure morphology was not a significant (P = .82) factor affecting microleakage; however, fissure type did significantly (P < .001) impact penetrability. No correlation was found between the extent of microleakage and penetrability. Conclusion: Application of sealants using phosphoric acid as a conditioning agent revealed superior results, while the use of adhesives was found to be unnecessary. [ABSTRACT FROM AUTHOR]

Objective: To determine and compare the microleakage of a conventional acid-etched, light-cured lingual retainer adhesive system with a recently developed antibacterial monomer-containing adhesive with and without etching. Methods: Sixty human mandibular incisors were separated into three groups of 20 teeth each, which received the following treatments: group 1 (control) = Transbond LR (3M Unitek), conventional lingual retainer bonding; group 2 = Clearfil Protect Bond (Kuraray Medical) with acid-etching; and group 3 = Clearfil Protect Bond without acid-etching. The wire in each was 0.0215-inch multistranded PentaOne (Masel Orthodontics). Samples were sealed with nail varnish, stained with 0.5% basic fuchsin, and sectioned. Transverse sections were evaluated under a stereomicroscope and scored for microleakage in millimeters at the composite-enamel interface. Statistical analysis was performed by Kruskal-Wallis and Mann-Whitney tests with Bonferroni correction. Results: Group 2 had less microleakage (0.11 ± 0.19 mm) than group 1 (0.26 ± 0.30 mm) or group 3 (0.24 ± 0.27 mm). However, the difference in the microleakage of the composite- enamel interface among all investigated groups was not significant (P > .05). Conclusion: The findings of this study do not speak against using an antibacterial monomer-containing self-etching adhesive to bond lingual retainers. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the present study was to compare two obturation techniques, i.e. Thermafil® and cold lateral condensation, in order to determine which one was most easily and rapidly learnt and applied by dental students. Methods: Fifty single-rooted teeth were instrumented by the crown-down technique. Five students were requested to obturate five teeth using the Thermafil technique and five using lateral condensation. A microleakage study was performed using a 2% aqueous methylene blue dye solution. The apical portion of teeth was sectioned into six sections and evaluated under a stereomicroscope. The presence of dye microleakage was considered when assessing every section. Results: Results were processed statistically by frequence of distribution and the Mann-Whitney test. A highly significant difference (P < 0.0001) was observed between Thermafil and cold lateral condensation techniques, the former resulting in lower leakage. Conclusion: The present study, though limited and only referring to a small group, suggested that characteristics of operators and the early repeated use of a technique may influence performance. [ABSTRACT FROM AUTHOR]

Objective: To evaluate and compare shear bond strength and marginal leakage of a new self-etch sealant to enamel of human permanent teeth versus those of a conventional sealant. Method and Materials: Forty-four premolar crowns were mounted to expose flat lingual surfaces and randomly assigned to 1 of 2 test groups: conventional sealant (group 1, control) and self-etch sealant (group 2). Sealants were expressed into hollow plastic cylinders placed on the mounted teeth and polymerized according to manufacturers' instructions. Shear bond strength was measured at a crosshead speed of 0.5 mm/min. Another 44 premolars were randomly assigned to either group 1 or group 2 for microleakage testing. Sealants were applied to the occlusal groove as per manufacturers' instructions, and specimens were thermocycled, stained, sectioned, and examined for marginal leakage. Results: The bond strength of conventional sealant to enamel was significantly (P < .05) higher than that of self-etch sealant. The conventional sealant showed significantly (P < .05) lower microleakage than the self-etch sealant. Conclusions: Pending clinical validation, the new self-etch sealant under investigation provides lower bond strength and greater marginal leakage than the control (sealant application following standard acid etching). [ABSTRACT FROM AUTHOR]