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Purpose: To assess the influence of two preparation techniques on the microleakage, marginal fit, and cement thickness of lithium disilicate veneers. Materials and Methods: A total of 24 human maxillary central incisors were divided randomly into two groups according to preparation technique (n = 12 each): a minimally invasive preparation with a butt-joint design (0.3-mm depth) and a chamfer finish line (group MP); and no preparation (group NP). All teeth were restored with lithium disilicate veneers cemented with photopolymerizable resin cement. Specimens were aged thermally (6,000 cycles of 5°C to 55°C) and mechanically (100,000 cycles at 100 N, 4 Hz). Specimens were immersed in fuchsin dye for 24 hours using a standard dye penetration technique, then sectioned and evaluated under a stereomicroscope (×20 magnification). Data were analyzed by ANOVA and Kruskal-Wallis tests (P < .05). Results: There was significant microleakage (P = .0163) at the cervical area compared to the proximal area. The marginal fit was similar, with no statistical difference (P = .212) between groups MP (153 ± 81 µm) and NP (111 ± 74 µm). Group MP showed a significantly (P = .006) reduced cement thickness at the cervical area (87 ± 27 µm) compared to group NP (210 ± 89 µm). Conclusion: Although the preparation technique was shown to influence the cement thickness, it did not show any influence on microleakage or marginal fit. [ABSTRACT FROM AUTHOR]

Purpose: To test the push-out force and marginal leakage of different screw hole-sealing methods in monolithic zirconia implant crowns.Materials and Methods: Ninety monolithic zirconia (Prettau, Zirkonzahn) specimens were milled with two different screw access hole designs: conventional smooth hole or threaded screw hole (for group PMMA-SC), and divided into five groups (n = 18) according to filling method: unbonded composite (UBC); bonded composite (BC); airborne-particle abrasion of screw hole and unbonded composite (ABR-UBC); airborne-particle abrasion of screw hole and bonded composite (ABR-BC); and PMMA screw plugs (PMMA-SC). Twelve specimens per group were subjected to static push-out force with a universal testing machine. Before testing, 6 specimens per group were stored in dry conditions, and 6 were kept in water storage (+37°C) for 7 days. For the remaining specimens (n = 6), cotton pellets were placed under the screw access hole fillings, and the specimens were immersed in 0.5% basic fuchsin solution for 2 weeks. Dye in cotton pellets was dissolved in 2 mL of water, and absorbances of the solutions were measured with a spectrophotometer at 465 nm. Data are reported as mean and SD. Statistical analysis was made using a generalized linear model with logarithmic transformation.Results: PMMA-SC specimens showed the highest push-out forces (P < .0001) and lowest fuchsin penetration (P = .009). Airborne-particle abrasion increased the push-out force and decreased the microleakage in composite groups. The storage conditions affected the results of both unbonded groups.Conclusion: The design and sealing method of the screw access hole affect push-out force and microleakage. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate the microtensile bond strength (μTBS) and marginal sealing ability of a self-adhering flowable composite between dentin and composite interfaces, as well as the microleakage of Class V restorations. Materials and Methods: The occlusal thirds of 40 third molars were removed and randomly divided into 4 groups according to the applied adhesive: Adper Easy One (AEO, 3M ESPE), Clearfil SE Bond (CSEB, Kuraray), Prime & Bond NT (PBNT, Dentsply) and a self-adhering flowable composite (Dyad Flow, DF, Kerr). Filtek Flowable (3M ESPE) resin composite crowns were then built up in the first three groups; in group DF, composite crowns were built up without the application of an adhesive. Thirty stick-shaped microspecimens were prepared per group, 10 of which were used for morphological observation of bonded interfaces by scanning electron microscopy (SEM) after decalcification. The remaining microspecimens underwent microtensile bond strength testing and the failure mode was analyzed. Microleakage evaluation was performed on 10 premolars per group in which standardized box-shaped Class V cavities were prepared. After 500 thermocycles, the premolars were immersed in 1% methylene blue for 24 h, and three slices from each tooth were observed under a stereomicroscope and scored. Statistical analysis was performed using one-way ANOVA, Student-Newman-Keuls and chi-square tests. Results: The PBNT group presented the highest μTBS values, followed by the CSEB and AEO groups, which did not differ significantly from each other. The DF group showed the lowest μTBS values. No significant differences in microleakage were observed among these four groups. Conclusion: Although individual usage of the self-adhering flowable composite showed the lowest bond strength, the same marginal sealing ability was observed as that of combining self-etching and etch-and-rinse adhesives with flowable composite. [ABSTRACT FROM AUTHOR]

Purpose: To evaluate shear bond strength and microleakage of a new self-etching/self-adhesive fissure sealant on prismless enamel compared with conventional fissure sealing. Materials and Methods: A total of 90 extracted third molars were assigned to 3 main groups: group 1: self-etching/ self-adhesive sealant, without acid etching; group 2: self-etching/self-adhesive sealant, with prior acid etching; group 3: conventional fissure sealing (control group). After specimen preparation, each group was divided into 3 subgroups according to storage time (1-day water storage, 3-month water storage, and 1-day water storage followed by 5000x thermocycling). The shear bond strength was determined with a universal testing machine, according to ISO standard 29022. Afterwards, the failure mode was analyzed. An additional 24 third molars were used for microleakage assessment. The fissure pattern was sealed in strict accordance with the manufacturers' instructions. After thermocycling, the dye penetration was examined. Data were analyzed using the Mann-Whitney U-Test at a significance level of 0.05. Results: The shear bond strength of the self-etching/self-adhesive fissure sealant without prior acid etching was significantly lower (4.3 MPa) than that of the self-etching/self-adhesive fissure sealant with prior acid etching (17.1 MPa) and the conventional fissure sealing (19.1 MPa). Microleakage was significantly lower in the control group (1.1%) and in the group with the self-etching/self-adhesive sealant with prior acid etching (0.8%) compared to the group that used the self-etching/self-adhesive material alone (49.4%). Conclusion: The self-etching/self-adhesive fissure sealant can be recommended for clinical use when enamel is etched with phosphoric acid. The self-etching/self-adhesive sealant without prior acid etching showed significantly inferior results. [ABSTRACT FROM AUTHOR]

This article discusses advancements in dental restorative materials and their implications for patient care. The use of dental amalgam, which has been popular due to its durability, is being questioned due to concerns about its biocompatibility. As a result, alternative materials such as resin-based composites, glass ionomer cement (GICs), and ceramic materials have gained popularity. Each material has its advantages and limitations, and dental professionals should consider factors such as the patient's oral health status and preferences when selecting the most suitable material. The article emphasizes the importance of personalized care and patient-centered discussions to ensure satisfaction and long-term oral health. [Extracted from the article]

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]

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 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: 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]

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]

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]

Purpose: To test the influence of thermomechanical loading and mode of cleaning the pulp chamber on coronal microleakage of adhesive sealings over root canal fillings. Materials and Methods: Root canals of molars were instrumented to size 60 taper .02 and filled with AH plus (Dentsply DeTrey) and a single gutta-percha cone size 55 taper .02. After removal of residual sealer with an alcoholmoistened foam pellet, different pretreatments were performed: groups 1 and 5: no further pretreatment; groups 2 and 6: use of a water cooled high-speed diamond bur; groups 3 and 7: etch-and-rinse with 37% H3PO4 for 10 s; groups 4 and 8: diamond bur and etching. Then Syntac (Ivoclar Vivadent) and two consecutive layers of Tetric flow (Ivoclar Vivadent) were applied. After placing glass-ionomer cement as a provisional restoration, teeth of groups 5 to 8 were additionally subjected to thermomechanical loading (chewing simulation of 200,000 cycles/50 N) and thermocycling (2880 cycles between 5°C and 55°C). A dye penetration test (methylene blue dye 5%, centrifugation for 3 min at 30 G) was used to evaluate linear dye penetration and dye penetration area. Statistical tests were performed using SPSS Win 12.0 (Kolmogorov-Smirnov test, two-way ANOVA, t-test). Results: Thermomechanical loading (TML) had a negative impact on coronal seal (two-way ANOVA, p < 0.001). Among TML groups, group 7 (etch-and-rinse) performed best, exhibiting the least influence of TML. Conclusion: For adhesive sealing of the pulp chamber floor, the etch-and-rinse technique combined with a flowable resin composite showed promising results. Nevertheless, a stabilizing restoration should be placed as soon as possible. [ABSTRACT FROM AUTHOR]

Dentin hypersensitivity commonly occurs due to opened dentinal tubules for many reasons. In our previous study, copine 7 (CPNE7) could induce dentin formation for an indirect pulp-capping model in vivo. This study aims to investigate the formation of tertiary dentin when CPNE7 is applied to intentionally exposed dentin with nothing over it in vivo, whether it affects microleakage of the teeth, and the penetration ability of CPNE7 molecules through dentinal tubules in vitro. Cervical dentin areas of 6 maxillary incisors of 5 beagles were exposed to a class V-like lesion, and 1 side of 3 maxillary incisors was adapted with recombinant CPNE7 protein for 5 min as the experimental group. The other side was the control group, and there was no treatment of ethylenediaminetetraacetic acid (EDTA) and CPNE7 after preparation. The defects were exposed without any restorations, and all beagles were sacrificed after 4 wk. The fluid penetration of exposed dentin areas was investigated by a microleakage-testing device and confocal laser scanning microscope. Tertiary dentin formation was confirmed with histological scanning electronic microscopic analysis. Tertiary dentin formation reduces dentinal fluid flow due to occluded tubules or discontinuity with primary or secondary dentin. The in vivo hypersensitivity model with the anterior teeth of beagle dogs showed newly formed tertiary dentin at the dentin-pulp boundary in recombinant CPNE7-treated teeth when compared with the untreated control group in histologic analysis. Scanning electronic microscopic analysis revealed occluded sites with mineral deposition of intratubular dentin. In the permeability test, the mean microleakage value of the CPNE7-treated group was significantly lower than that of the control group (P < 0.05). The tubular penetration of rhodamine B-combined CPNE7 was confirmed under confocal laser scanning microscope. CPNE7 induces formation of tertiary dentin through shallowly exposed dentinal tubules, which decreases dentin permeability. [ABSTRACT FROM AUTHOR]

The article focuses on tremendous attention and effort continue to be directed to the study of dental adhesion the bond to tooth structure adequate for clinical success but obviously a journal dedicated to dental adhesion believes we still have much yet to be achieved. Topics include the possible treatment options adhesive dentistry brings, and the greatest need for society comes from the global burden of dental caries.

Brief Background To evaluate the marginal integrity of nanohybrid composite and the amount of microleakage occurrence at the interface of the tooth and nanohybrid composite restoration during carbamide peroxide bleaching with and without a protective coating. Materials and Methods Sixty mandibular premolars were included in the study. Class V cavities were prepared and restored with nanohybrid composite restoration and divided into Group 1: bleaching with carbamide peroxide without G coat plus, Group 2: bleaching with carbamide peroxide with G coat plus, applied over the restorative surface and margins. Group 3: without bleaching procedure. Samples in Groups 1 and 2 were mounted in dental stone and bleaching trays were custom fabricated. 15% carbamide peroxide was applied for 2 weeks. Samples were sectioned buccolingually and subjected to thermocycling, immersed in 2% methylene blue for 24 hours. Depth of dye penetration was evaluated under stereomicroscope. Results The amount of microleakage due to bleaching in teeth without coating is more when compared with the application of G coat plus. Control group also showed a higher amount of microleakage compared to Group 1 and 2. Summary and Conclusions Significant reduction in microleakage was seen in Group 2 when compared to other groups. By using G coat plus during bleaching, microleakage and possible replacement of composite restoration can be avoided [ABSTRACT FROM AUTHOR]

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Introduction: The purpose of this study was to compare the incidence of dentinal crack formation after root canal preparation using ProTaper Next, OneShape and Hyflex electrodischarge machining (HEDM). Materials and Methods: A total of 75 extracted mandibular premolars were selected. The root canals were instrumented using ProTaper Next, OneShape and HEDM rotary files. All roots were horizontally sectioned at 3, 6 and 9 mm from apex with slow-speed saw under water cooling. The sections were observed under a stereomicroscope at x25 to determine the absence or presence of crack. Data were analyzed using post hoc test and one-way ANOVA. Results: ProTaper Next and HEDM produced significantly less cracks than OneShape. Conclusion: Within the limitation of this in vitro study, it can be concluded that nickel-titanium instruments may cause cracks on the root surface. ProTaper Next and HEDM tend to produce less number of cracks as compared to OneShape. [ABSTRACT FROM AUTHOR]

Aim of the Study: The aim of this study was to compare the apical sealing ability of two single-cone filling materials when sealed with different types of root canal sealers. Materials and Methods: Eighty extracted maxillary and mandibular canines were selected and their crowns were cut. The root canals were prepared using ProTaper Universal rotary system until size F4 and then divided into seven experimental groups (n = 10 each) and two control groups (n = 5 each). Samples of Groups 1, 2 and 3 were filled with single-cone gutta-percha and AH Plus, MTA Fillapex and EndoSequence BC, respectively. Samples of Groups 4, 5 and 6 were filled similar to the previous groups with the exception of using a single-cone CPoint. Samples of Group 7 were filled with cold gutta-percha lateral condensation technique. To assess apical microleakage, the apical linear dye penetration was measured microscopically and data were statistically analyzed. Results: All experimental groups showed significantly different dye apical leakage values (P = 0.000). No significant differences were found between Groups 1, 2, 4, 6 and 7 (P < 0.05). The lowest mean leakage value was observed in Group 6 (0.95 ± 0.56 mm) while Groups 3 (2.68 ± 0.71 mm) and 5 (2.61 ± 0.71 mm) showed significantly higher mean leakage values. Conclusions: The lowest apical leakage value was observed with single-cone CPoint/EndoSequence BC but without significant differences when compared with single-cone gutta-percha/AH Plus, single-cone gutta-percha/MTA Fillapex, single-cone CPoint/AH Plus and lateral condensation technique. Higher apical leakage values were observed with single-cone gutta-percha/EndoSequence BC and CPoint/MTA Fillapex. [ABSTRACT FROM AUTHOR]

Background and Objectives: Image processing and enhancement filters can significantly improve the diagnostic value of digital radiographs. Evidence shows that increasing the contrast and filtering improve the diagnostic accuracy for caries detection. This study sought to assess the diagnostic accuracy of original and enhanced digital radiographs for the detection of approximal and occlusal caries. Subjects and Methods: In this experimental study, incipient carious lesions were artificially created on 120 proximal and occlusal surfaces of human extracted permanent molar and premolar teeth. After mounting the teeth in wax, digital radiographs were obtained using photostimulable phosphor plates and enhanced by enhancement filters 1, 2 and 3 with/without denoising. Two oral and maxillofacial radiologists blinded to filtering viewed the radiographs and filled out a chart. A definite diagnosis was made by a pathologist by observing the samples under a stereomicroscope (gold standard). Data were analyzed using SPSS software version 16. Interobserver agreement was calculated using kappa statistics. Chi-square test was used to assess the correlation between qualitative variables. Results: Assessment of sensitivity, specificity, accuracy, positive predictive value and negative predictive value showed that enhancement filter 2 without denoising was the most efficient and original radiographs (filter free) were the least efficient radiographs for the detection of carious and sound surfaces. Application of filters significantly increased the accuracy of caries detection on digital radiographs. The lowest diagnostic accuracy was noted for the detection of enamel lesions on original radiographs (52%). Enhancement filter 2 plus denoising was the best filter for the detection of these lesions (79.25%). No significant difference was noted among different filters for detection of carious and sound surfaces but enhanced and original radiographs were significantly different in visualization and detection of caries (P < 0.05). Conclusion: Application of enhancement filters, particularly enhancement filter 2 with/without denoising, increases the accuracy of caries detection on digital radiographs. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate retention & fracture resistance of different fibre posts. Methodology: 90 extracted human permanent maxillary central incisors were used in this study. For retention evaluation, after obturation, post space preparation was done in all root canals and posts were cemented under three groups. Later, the posts were grasped & pulled out from the roots with the help of a three-jaw chuck at a cross-head speed of 5mm/min. Force required to dislodge each post was recorded in Newtons. To evaluate the fracture behavior of posts, artificial root canals were drilled into aluminium blocks and posts were cemented. Load required to fracture each post was recorded in Newtons. Results: The results of the present study show the mean retention values for Fibrekleer Parallel post were significantly greater than those for Synca Double tapered post & Bioloren Tapered post. The mean retention values of the Double tapered post & the tapered post were not statistically different. The Synca Double tapered post had the highest mean load to fracture, and this value was significantly higher than those of FibreKleer Parallel & Bioloren Tapered post. The mean fracture resistance values of Parallel & tapered post were not statistically different Conclusions: This study showed parallel posts to have better retention than tapered and double tapered posts. Regarding the fracture resistance, double tapered posts were found to be better than parallel and tapered posts. [ABSTRACT FROM AUTHOR]

Aims and Objectives: Root canal preparation and obturation are of great importance in endodontics. Its purpose is to eliminate pulpal and periradicular disease. The aim of this study was to compare coronal bacterial microleakage in prepared root canals using Neoniti A1 and Reciproc files that obturated with lateral compaction, single cone gutta-percha, and hybrid (tapered cone/lateral compaction) methods. Materials and Methods: In this ex vivo study, a total of 110 single-rooted mandibular first premolars were choose and randomly divided into two study groups A and B (each 45) that one group was prepared with Reciproc and another with Neoniti A1 and negative and positive control groups (each 10). Each group divided into three subgroups of 15 each and obturated using a single cone, lateral compaction, and hybrid (tapered cone/lateral compaction) techniques. For evaluation of coronal leakage, "two-chamber setup" was used. The solution of enterococcus faecalis culture was injected in the upper chamber and incubated. If the bacteria pass through the canal and obturation materials, the lower chamber becomes turbid. TSB medium in the lower chamber (apex) were investigated every day in terms of occurrence of turbidity, and the duration of occurrence of leakage was recorded. The data were analyzed using Chi-square test. Results: Data analysis showed that in each group the difference in percentages between subgroups was statistically significant (P = 0.003). So that the highest and the lowest amount of leakage in both groups were related to lateral compaction and hybrid techniques, respectively. Conclusion: Under the conditions of this study, independent of the instrument used for canal preparation, hybrid method and then single-cone technique, however, were more effective in the prevention of coronal leakage than lateral condensation technique. [ABSTRACT FROM AUTHOR]

Aim of the Study: The aim of this study was to compare and evaluate the sealing ability of four root end filling materials mineral trioxide aggregate (MTA)-Plus, Biodentine, MTA (MTA Angelus) and glass ionomer cement (GIC) using fluid filtration method. Materials and Methods: Forty-four extracted, human single-rooted teeth were collected. The crown of each tooth was decoronated 2 mm above the cementoenamel junction. Canals were negotiated, instrumented, obturated using lateral compaction method. The access cavities were sealed with Cavit. Root end resection and apical root end cavity preparations of 4 mm were made in each specimen. The selected roots were then randomly divided into four groups (n = 11) and restored as follows. Group 1 ' GIC, Group 2 ' MTA (MTA Angelus), Group 3 ' Biodentine, and Group 4 ' MTA Plus. The apical microleakage of each specimen was assessed using fluid filtration method at 72 h, 1 month and 3 months. Microleakage in each specimen was recorded in mm (millimeter) and converted to μl/min/cm H2O. Results: MTA Angelus showed least microleakage followed by Biodentine and MTA Plus. Least sealing ability was seen with GIC. There was statistically significant difference between all the materials at various time intervals. Conclusion: MTA Angelus showed superior sealing ability as a retrograde filling material followed by Biodentine and MTA Plus. [ABSTRACT FROM AUTHOR]

Aim The aim of the present study was to evaluate the effect of the application of a hydrophobic resin on the microleakage of Cl V composite resin restorations using a universal adhesive system applied in the self-etch ( SE) and etch-and-rinse ( ER) modes. Method Cl V cavities were prepared on the buccal surfaces of 64 human premolar teeth and divided into four groups ( n = 16): ER, ER with hydrophobic resin ( ERH), SE, and SE with hydrophobic resin ( SEH). Microleakage at occlusal and gingival margins was evaluated using 0.5% methylene blue dye penetration technique under stereomicroscope at 40 × magnification. Data were analyzed using Kruskal-Wallis and Mann-Whitney U-tests ( P < 0.05). Results At the enamel margins, the ER group had significantly less microleakage than the SE and SEH groups ( P < 0.001), but had no significant difference compared with the ERH group ( P > 0.05). There was also no statistically-significant difference between the SE and SEH groups ( P > 0.05). At the dentinal margins, the SE group had significantly less microleakage compared with the ER ( P < 0.001) and ERH groups ( P = 0.005). Furthermore, microleakage of the SEH group was significantly less than the SE group ( P < 0.001). Conclusion Applying an extra layer of hydrophobic resin significantly decreased microleakage in the SE mode at the dentinal margin, but had no significant effect in the ER mode. [ABSTRACT FROM AUTHOR]

The advancement of restorative materials and techniques continues to enhance the clinical success of numerous restorative procedures. Despite these new innovations, microleakage persists as one of the main causes of restoration failure. Microleakage tests provide useful information on the performance of restorative materials, and different techniques for assessing microleakage have been developed and used. These tests include the use of dyes, radioactive isotopes, air pressure, bacteria, neutron activation analysis, and artificial caries. However, little has been done to determine the cause, mechanism, and nature of microleakage. Therefore, this review outlines and discusses the currently available microleakage assessment tools. [ABSTRACT FROM AUTHOR]

Aims: The aim of the present study was to evaluate and compare the sealing ability of root canal obturation after the application of fluoride varnish (MI Varnish) containing 5% sodium fluoride and casein phosphopeptide-amorphous calcium phosphate, fluoride varnish, and AH Plus and AH-Plus as root canal sealer by bacterial penetration test.Materials and Methods: Root canals of 65 single-rooted and single-canalled teeth were prepared. They were divided into three experimental groups (n = 15) and two control groups (n = 10). The root canal walls in Group I were coated with AH Plus, Group II were coated with AH Plus and fluoride varnish, and Group III were coated with fluoride varnish. All the teeth were obturated with gutta-percha using the lateral condensation technique. Enterococcus faecalis were used as test bacteria to determine the leakage during 100 days.Statistical Analysis: The data were analyzed using log-rank test and Kaplan-Meier survival analysis.Results: Group III showed significantly less bacterial penetration as compared to Group I (P = 0.01) and Group II (P = 0.03). However, there was no statistical significance between Groups I and II (P = 0.672).Conclusions: It can be concluded from the present study that fluoride varnish can be used as a root canal sealer. However, further in vitro and in vivo studies are required. [ABSTRACT FROM AUTHOR]

Background: Microleakage around dental restorative material and strength to withstand the masticatory forces is major problem in dentistry. Instead, many new materials available, very few actually bond to tooth surface and bear masticatory load.Aim: The aim of this study is to evaluate and compare the microleakage and compressive strength of Ketac Molar, Giomer, Zirconomer, and Ceram-x.Materials and Methods: For the evaluation of microleakage, Class V cavities were prepared on sixty human premolar teeth and divided into four study groups (n = 15): Group I (Ketac Molar), Group II (Giomer), Group III (Zirconomer), and Group IV (Ceram-x). The samples were thermocycled and subjected to dye penetration test. The sections were made and evaluated under stereomicroscope at × 40 magnification. For the compressive strength evaluation, sixty cylindrical specimens were fabricated measuring 5 mm × 6 mm and grouped into four study groups (n = 15): Group I (Ketac Molar), Group II (Giomer), Group III (Zirconomer), and Group IV (Ceram-x). All were then subjected to the Universal Testing Machine at crosshead speed of 1 mm/s.Statistical Analysis Used: The data were analyzed using paired t-test and ANOVA.Results: The microleakage was found insignificant (P > 0.05) for all study groups, with Giomer showing maximum followed by Zirconomer, Ceram-x, and Ketac Molar. The compressive strength was found to be highly significant (P < 0.01) with the maximum score for Giomer followed by Ceram-x, Zirconomer, and Ketac Molar.Conclusion: The sealing ability was maximum in Ketac Molar, Zirconomer, Ceram-x, and Giomer whereas the compressive strength was maximum for Giomer followed by Ceram-x, Zirconomer, and Ketac Molar. [ABSTRACT FROM AUTHOR]

Aim: The aim of this study was to evaluate microleakage under orthodontic ceramic brackets bonded with direct and different indirect bonding techniques and adhesives using micro-computed tomography. Materials and methods: A total of 30 human maxillary premolars were randomly separated into five groups with six teeth in each group. In group I, teeth were bonded directly with Transbond XT (3M Unitek). In group II, group III, group IV, and group V, teeth were bonded through an indirect technique with Custom I.Q. (Reliance Orthodontic Products), Sondhi Rapid-Set (3M Unitek), RMbond (RMO), and Transbond IDB (3M Unitek), respectively, following the manufacturer's instructions. Micro-CT system model 1172 of Skyscan (Kontich, Belgium) was used to scan all samples. NRecon (Skyscan) version 1.6, CT-Analyser V.1.11 (Skyscan), and TView (SkyScan, Bvba) software programs were used for microleakage evaluation. Microleakage values between the test groups were assessed using the Kruskal-Wallis test, while the Wilcoxon signed rank test was used for within-group comparisons. The level of significance was set at P < 0.05. Results: According to the Kruskal-Wallis analysis of variance test, there were no significant differences among the tested groups, with regard to volume and percentage (microleakage/region of interest × 100) of microleakage values (P < 0.05). The Wilcoxon signed rank test showed that coronal microleakage volume and percentage values significantly differed for RMbond and Transbond IDB groups. Limitations: In the study, only ceramic brackets were used and microleakage into mini gaps did not show up on the micro-CT image because 50% silver nitrate solution could not penetrate into mini gaps which are smaller than silver nitrate particles. Conclusion: Use of direct and indirect bonding techniques with different adhesives did not significantly affect the amount of microleakage. [ABSTRACT FROM AUTHOR]

Background: Self-etching adhesives might be an effective alternative to conventional phosphoric acid etchants in conditioning the enamel surface. The objective of this in vitro study was to evaluate and compare microleakage of a fissure sealant applied following the use of two brands of self-etching adhesives. Materials and Methods: 78 sound maxillary first permanent premolars received enameloplasty and randomly distributed into 3 different groups according to enamel surface conditioning before sealant (ClinproTM) application: (1) Conditioning with 35% phosphoric acid (ScotchbondTM Etchant) (Group 1); (2) conditioning with self-etching adhesive (Xeno®V) (Group 2); and (3) conditioning with self-etching adhesive (Optibond® All-In-One) (Group 3). Samples were: Thermocycled, stained, sectioned, and examined for marginal microleakage. Results: Marginal leakage was significantly lower with conventional etching than with self-etching adhesives while Xeno®V resulted in resulted in significantly less microleakage than Optibond® All-In-One. Conclusions: Marginal leakage of the self-etching adhesives (Xeno®V and Optibond® All-In-One) was found to be significantly more compared to that of the conventional phosphoric acid etching even with enamel preparation. Etching enamel with phosphoric acid is still essential for sealing the enamel-sealant interface. [ABSTRACT FROM AUTHOR]

Objectives To critically appraise experimental ex vivo research that has focused on secondary caries, and to offer possible explanations for the seemingly poor correlation to clinical observations. Methods The literature relating to the etiopathogenesis or prevention of secondary caries gained from experimental ex vivo research was reviewed, with particular emphasis on microleakage and artificial caries-like lesions. Results It is doubtful whether a caries wall lesion can exist independently of an outer enamel caries lesion. Microleakage experiments apparently continue to emerge regardless of multiple reviews questioning the reliability and validity of the method. Several of the approaches used to generate artificial caries-like lesions are very aggressive. Remarkably little discussion has evolved about how these aggressive approaches create microenvironments that do not occur in reality. Corrosion- and biodegradation products may influence the biofilm qualitatively and quantitatively and it is difficult to replicate these variables in any ex vivo environment. Clinical data sampling method, patient demography as well as study methodology influences the incidence and prevalence estimates of secondary caries. Clinical results based on clinical work in settings where cost per unit time is of nominal concern do not provide any indications on how the restorative material will perform when placed by the average dentists in the mouths of their spectrum of patients during a busy workday. Significance and recommendations The term “wall lesion” including its variants is ill defined, has been, and is still being used indiscriminately. Stakeholders should avoid using this ambiguous label due to its connotation to an entity that does not exist per se. [ABSTRACT FROM AUTHOR]

Aim: The present study evaluated the influence of the working length and foraminal enlargement on the sealing ability and anatomy of the apical region of the root.Materials and Methods: Fifty-five roots were divided into three groups: G1, instrumentation 1 mm short of the major foramen; G2, instrumentation in the limit of the apical foramen; and G3, instrumentation 1 mm beyond the foramen. All groups were prepared using nickel-titanium rotary files and obturated with AH Plus and Gutta-percha. Photomicrographs were taken using a scanning electron microscopy (SEM) before instrumentation, after instrumentation with each file, and after root canal filling. Moreover, bacterial microleakage with Enterococcus faecalis was performed.Results: The results were analyzed using Mann-Whitney, Friedman, Kruskal-Wallis and Kaplan-Meier tests at a significance level of 5%. The cemental canal was uninstrumented in G1. No statistical differences regarding foramen deviation was observed when compared G2 and G3 (P > 0.05). SEM analysis showed that G2 and G3 resulted in good apical foramen obturation. Microleakage showed no statistically significant differences between all of the groups tested.Conclusions: Under the conditions of this study, it can be concluded that foramen enlargement resulted in more apical deviation; however, no differences in bacterial microleakage was observed among the experimental groups. [ABSTRACT FROM AUTHOR]

The aim of this study was to compare the coronal sealing ability of six different dental materials: Three MTA-based cements and three established restorative materials by in vitro dye penetration method. For in vitro infiltration experiments, seventy extracted single-rooted human teeth were used. After crowns of teeth were reduced, root canals were prepared, and filled with gutta-percha cone. Teeth were randomly divided into 6 groups with 10 teeth per group. The orifice of each tooth was prepared to 3 mm depth and filled with the following materials: (I) ProRoot WMTA; (II) EndoCem Zr; (III) Angelus White; (IV) LuxaCore; (V) Fuji II LC; and (VI) Elite. After 5,000 cycles of thermocycling between 5°C and 55°C, dye penetration of each specimen was measured. The order of less dye infiltration of coronal filling materials was: ProRoot WMTA

PURPOSE. This in-vitro study was designed to evaluate retention forces, microleakage and plastic deformation of a prefabricated 2-implant bar attachment system (SFI-Bar, Cendres+Métaux, Switzerland). MATERIALS AND METHODS. Two SFI implant-adapters were torqued with 35 Ncm into two implant analogues. Before the tube bars were finally sealed, the inner cavity of the tube bar was filled with liquid red dye to evaluate microleakage. As tube bar sealing agents three different materials were used (AGC Cem (AGC, resin based), Cervitec Plus (CP; varnish) and Gapseal (GS; silicone based). Four groups with eight specimens each were tested (GS, GS+AGC, AGC, CP). For cyclic loading, the attachment system was assembled parallel to the female counterparts in a chewing simulator. The mean retention forces of the initial and final ten cycles were statistically evaluated (ANOVA, a=.05). RESULTS. All groups showed a significant loss of retention forces. Their means differed between 30-39 N initially and 22-28 N after 50,000 loading cycles. No significant statistical differences could be found between the groups at the beginning (P=.224), at the end (P=.257) or between the loss of retention forces (P=.288). Microleakage occurred initially only in some groups but after 10,000 loading cycles all groups exhibited microleakage. CONCLUSION. Long-term retention forces of the SFI-Bar remained above 20 N which can be considered clinically sufficient. The sealing agents in this study are not suitable to prevent microleakage. [ABSTRACT FROM AUTHOR]

Objective: The aim of the study was to compare in Class V composite restorations marginal leakage measurements obtained with micro-computed tomography (micro-CT) and scanning electron microscopy (SEM) observations. Methods: Class V cavities were prepared on 10 human molars and restored using Optibond FL (Kerr, Orange, CA, USA) and Premise Flowable (Kerr). Sealing ability was evaluated by assessing silver-nitrate penetration depth along enamel and dentin margins. Leakage was quantified using a scoring system. Micro-CT analysis provided 502 cross-sectional images for each tooth. Microleakage evaluation was performed first on three cross-sections corresponding to the sections examined by SEM, then on all 502 of the obtained micro-CT images. SEM observations were performed first at 20X magnification, then, if showing a zero score, at 80X magnification. Enamel and dentin microleakage scores assigned to corresponding sections through micro-CT and SEM (20X) were compared (Wilcoxon signed-rank test, α=0.05). Results: No statistically significant difference in leakage scores emerged between micro-CT and 20X-magnification SEM. Eight tooth sections that were given a zero score under SEM at 20X magnification showed to be infiltrated at the higher magnification (80X). For five teeth a higher score was assigned following scanning of 502 cross-sections than based on the observation of three sections. Conclusions: Micro-CT presents as a valid, nondestructive in vitro method to quantitatively evaluate marginal leakage of adhesive restorations. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the microleakage and marginal gap of various luting materials after cementing ceramic crowns. Methods: Cervical margins of human molars were designed as circular chamfers. Cementation of full-contour ceramic crowns was conducted with zinc-phosphate cement (Harvard cement), resin cement (Panavia F 2.0) and self-adhesive resin cements (RelyX Unicem, BifixSE, MaxCem Elite, PermaCem2.0, G-Cem). Aging of specimens was performed in artificial saliva, at 37 °C for four weeks and thermocycling. The marginal gap was measured with a scanning electron microscope and silver precipitation within the microleakage. All data were compared statistically. Results: Independent of the margin preparation, the highest median value for microleakage was 320.2 μm (Harvard cement), and the lowest was 0 μm (Panavia F 2.0). The median value for enamel was 0 μm and for dentin 270.9 μm (p < 0.001), which was independent of the luting material. The marginal and absolute marginal gaps were not significantly different between the tested materials. There was no correlation between microleakage and the marginal gaps. Conclusion: Significant differences in microleakage were found between the tested luting materials (p < 0.05). Independent from the luting materials, the microleakage in dentin showed significantly higher values than in enamel. [ABSTRACT FROM AUTHOR]

The aim of this in vitro study was to assess dye microleakage and sealing ability of four dental materials: a polycarboxilate cement (Adhesor Carbofine® - Spofa Dental), a glass ionomer cement (Kavitan Plus®- Spofa Dental), a composite resin (Core-It®- SpiDent) and a MTA based cement (MTA Fillapex®- Angelus). Forty, extracted, human teeth with single root canals were selected for this study. The teeth were randomly divided into four study groups and one control group. The root canals were instrumented and filled with gutta-percha and sealer. Root-ends were resected and 3 mm deep cavities were prepared. Root-end cavities were filled, each with a type of material. Methylene blue dye was used for determination of dye leakage. Afterwards, Scanning Electron Microscopy was used to evaluate the sealing ability of each material. Kolgorow-smirnow z test was used to determine the type of data distribution. One-way analysis of variance (ANOVA) followed by a Tukey test were used to determine the statistical difference between groups, with P < 0.05 set as significant. All the four sealers produced apical leakage to a certain extent and there was no statistically significant difference between the five experimental groups. For SEM evaluation, the results showed that there is a statistically significant difference between the control group and the Adhesor Carbofine group. MTA based cement provides leakage results comparable to other commonly used root-end filling materials. [ABSTRACT FROM AUTHOR]

Introduction: The aim of the present study was to evaluate the effect of glass ceramic insert in the sandwich technique to reduce microleakage in class II composite resin restorations. Methods: Sixty sound human upper second premolars were selected and randomly divided into six groups (n=10). Class II boxonly cavities were prepared in distal aspects of each tooth with gingival margin located approximately 0.5 mm below the CEJ. Group A (Control) was restored incrementally with Tetric Ceram and a total-etch bonding technique. Group B and C were restored with sandwich technique using a compomer (Compoglass F) or flowable composite resin (Tetric Flow) as the lining material at gingival floor, respectively. Group D, E and F were represented in the same way as group A, B and C and a glass ceramic insert was added to the composite bulk. The specimens were thermo-mechanically cycled, and then immersed in 0.5 % basic fuschin for 24 hours. Dye penetration was detected using a sectioning technique. Results: No significant difference was found between total-etch bonding and sandwich techniques. The placement of an insert caused an increase in microleakage in all groups significantly (P < 0.05). Group D (no liner/ with glass insert) showed the highest amount of microleakage and Group A (no liner/ without glass insert) resulted in the lowest amount of total microleakage. Conclusion: Placement of glass ceramic insert could not decrease gingival leakage. According to the limitation of this study a composite resin restorations with incremental technique is recommended. [ABSTRACT FROM AUTHOR]

Aim: Composite resins have undergone various advances since their introduction, but their polymerization shrinkage remains a problem. Shrinkage can cause debonding of the restoration and can contribute to postoperative sensitivity, secondary caries, marginal staining and eventual failure of the restoration. So, our aim is to compare the effect of two different placement techniques and two different curing modes in reducing the marginal microleakage of two different composites in Class II cavities, where oblique and horizontal placement techniques and ramp & pulse curing modes of LED are used during the restoration. Materials and Methods: Standardized slot preparations were prepared in 80 human multi-rooted teeth. The teeth were randomly divided into four groups. Group A and B: Restored with Filtek P60 (3M, ESPE), Group C and D: Restored with Filtek P90 (3M, ESPE). All groups were further divided into sub-groups on basis of placement technique and curing mode. The samples were stored in distilled water, followed by thermocycling and immersed in 2% methylene blue. The samples were sectioned and evaluated for microleakage at the gingival margin with an optical stereomicroscope. Results: P60 composite when placed in the cavity with oblique incremental technique and cured with ramp mode of LED showed highest mean microleakage. There is no significant difference between horizontal and oblique placement technique (p=0.80); Pulse-curing and the ramp-curing mode (p=0.62). Conclusion: In restoring deep class II cavities, the use of a low-shrink composite with the oblique placement technique and ramp curing mode of LED is recommended to overcome the problem of marginal microleakage. [ABSTRACT FROM AUTHOR]

Liners and bases are a class of dental materials that provide added protection for the health and well-being of a tooth being restored. They help prevent postoperative sensitivity resulting from an incomplete dentinal seal. Some practitioners use them, while others choose not to. In this case report, a resin-modified glass-ionomer (RMGI) liner was utilized in deep restorations on premolars that had old, existing amalgam restorations and were experiencing microleakage and sensitivity problems. The materials and technique used allowed for conservative treatment while delivering an esthetic and functionally pleasing result. [ABSTRACT FROM AUTHOR]

Objectives to complement our previous work by testing the null hypotheses that with short curing times and high DC, TPO-based resin composites would exhibit (1) higher polymerization stresses and consequently display (2) higher temperature rise and (3) higher flexural modulus, flexural strength and hardness, compared to a conventional CQ-based experimental composite. Methods Two experimental resin composites using either Lucirin-TPO or camphorquinone/DMAEMA as photoinitiators were prepared. Light curing was carried out using spectral outputs adapted to the absorption properties of each initiator. Different irradiation protocols were selected (0.5, 1, 3, 9 s at 500, 1000 and 2000 mW/cm 2 for Lucirin-TPO based composites and 20 or 40 s at 1000 mW/cm2 for Lucirin-TPO and camphorquinone-based composites). Degree of conversion (DC) was measured in real time by means of FT-NIR spectroscopy. Pulpal temperature rise (Δ T ) was studied in a tooth model. Polymerization stress was monitored using the Bioman instrument. For cured specimens, flexural modulus and flexural strength were determined using a three point bending platform and Vickers hardness was determined with a microhardness indentor on samples prior to and after 24 h incubation in 75/25 ethanol/H 2 O. Premolars were restored with both materials and microleakage at the teeth/composite interfaces following restoration was assessed. Results Lucirin-TPO-based composites irradiated at radiant exposures of 3 J/cm 2 and more exhibited significantly higher DCs, associated with increased flexural moduli and hardness compared to CQ-based composites. For an ultra-short irradiation time of 1 s at 1000 mW/cm 2 , TPO-composites displayed similar polymerization stresses compared to CQ-controls with yet a 25% increase for flexural modulus and 40% increase for hardness measured after EtOH/H 2 O sorption. Higher stress rates were however observed in all curing protocols compared to CQ-composites. Microleakage was similar between TPO and CQ-composites irradiated at 1000 mW/cm 2 for 3 and 20 s respectively, while a significant increase was observed for TPO-composites irradiated for 1 s. Δ T measured through a 0.6 mm thick dentin layer were all below 5.5 °C; TPO-composites exhibited similar or lower values compared to controls. Significance The use of Lucirin-TPO in resin composites along with appropriate curing conditions may allow for a major reduction of irradiation time while improving mechanical properties. The amount of stress observed during polymerization in TPO-based composites can be similar to those using CQ and the cohesion at the restoration-tooth interface was not affected by short curing times. Contrary to other studies, we found that the temperatures increases measured during polymerization were all well below the 5.5 °C threshold for the pulp. [ABSTRACT FROM AUTHOR]

Objective: To evaluate microleakage when two types of retainer wires were bonded with two light cured and a self cured lingual retainer composites. Materials and Methods: Total 120 freshly extracted human mandibular incisor teeth were collected and separated into six subgroups of 20 teeth each. Two different wires, a 0.036 inch hard round stainless steel (HRSS) wire sandblasted at the ends and 0.0175 inch multistranded wire bonded onto the lingual surfaces of the incisors with three different types of composite resins of 3M company; Concise Orthodontic (self-cure), Transbond XT (lightcure) and Transbond LR (light-cure). Specimens were further sealed with a nail varnish, stained with 0.5% basic fuchsine for 24 hours, sectioned and examined under a stereomicroscope, and scored for microleakage for the enamel-composite and wire-composite interfaces. Statistical analysis was performed by Kruskal-Wallis and Mann-Whitney U-tests. Results: For HRSS wire, at the enamel-composite interface, the microleakage was least with Transbond LR followed by Concise Orthodontic and greatest for Transbond XT (p<0.05). At the wire composite interface too, the microleakage was in order of Transbond LR

Objective: This in vitro study evaluated and compared the microleakage of three sealers; Endosequence bioceramic (BC) sealer, AH Plus and Epiphany. Materials and Methods: Study was done on 75 extracted human single rooted permanent teeth, which were decoronated and the root canals were instrumented. The specimens were randomly divided into three groups (n = 25) and obturated by continuous wave condensation technique. Group A: using Endosequence BC, Group B: using AH Plus sealer, Group C: using Resilon Epiphany system. Microleakage was evaluated using dye penetration method. Teeth were split longitudinally and then horizontally markings were made at 2, 4 and 6 mm from the apex. Dye penetration evaluation was done under stereomicroscope (30X magnification). Results: The dye penetration in Group B was more than in Group A and C in both vertical and horizontal directions, suggesting that newly introduced BC sealer and Epiphany sealer sealed the root canal better compared to AH Plus Sealer. Conclusion: Newer root canal sealers seal the root canal better but cannot totally eliminate leakage. [ABSTRACT FROM AUTHOR]

Objectives: To investigate the effect of acidic solution on surface roughness and microleakage of tooth-colored restorative materials. Materials and Methods: A 160 box-shaped cavities were prepared on the buccal surfaces of 160 human molars, and assigned to four groups: Group A restored with Ketac™ Molar Easymix, Group B with Fuji II™ LC, Group C with Ketac™N100, and Group D with Filtek™ Z250, and subdivided into study and control groups (n = 20). Study groups were immersed in lemon juice (pH = 2.79) for 24 h, whilst controlgroups in deionized distilled water. All samples were immersed in 2% methylene blue dye, sectioned into two equal halves for surface roughness, and microleakage tests. Data were analyzed using Mann-Whitney and Kruskal-Wallis tests at P < 0.05. Results: There was a significant difference in surface roughness of Ketac™ Molar, Fuji II™LC, and Ketac™N100. No significant difference was found in microleakage of Ketac™ Molar and Fuji II™LC; however, there were significant differences in the gingival margin of Ketac™N100, and the occlusal margin of Filtek™Z250. Conclusions: All glass ionomer cements were eroded after exposure to the acidic drink. Filtek™ Z250 and Ketac™ Molar Easymix showed more microleakage. All materials showed more microleakage at the gingival margins. [ABSTRACT FROM AUTHOR]

Objectives: Selective caries removal involves sealing of carious dentine beneath restorations, which might decrease their marginal integrity and increase the susceptibility for secondary caries and microleakage. The present study compared these marginal characteristics of restorations in selectively and completely excavated teeth. Methods: In 32 premolars, shallow and deep artificial lesions were created on pulpo-axial walls of mesial-distal-occlusal cavities, with mesial and distal margins located in enamel and dentine, respectively. Demineralised dentine was either removed or left before adhesively restoring the teeth (n = 8), which were then submitted to thermo-mechanical cycling. The integrity of gingivo-cervical margins was assessed using scanning electron microscopy. In half of each margin, caries was induced adjacent to restorations using a continuousculture biofilm model, and resulting lesions were evaluated using transversal microradiography. The other half of each margin was used to assess microleakage. Results: Integrity or microleakage of margins located in enamel did not differ significantly between groups, and bacterial biofilms did not induce distinct caries lesions in enamel. Dentinal margins in teeth with deep compared with shallow lesions showed a significantly higher proportion of marginal imperfections, gaps and microleakage ( p ≤ 0.05, Mann- Whitney/Χ²-test). In contrast, neither marginal integrity nor microleakage differed significantly between completely and selectively excavated teeth ( p > 0.05). Dentinal mineral loss adjacent to restorations did not differ significantly between groups ( p > 0.80). Conclusions: The marginal characteristics of restorations were affected by the depth of sealed or excavated lesions, but not by the performed caries excavation. This study did not find selective excavation detrimental for restoration integrity in vitro. Clinical significance: Selective excavation of deep lesions was shown to reduce pulpal risks, whilst leaving caries beneath restorations is feared to compromise the marginal characteristics of the subsequently placed restoration. Based on the present in vitro study, such assumptions cannot be supported. [ABSTRACT FROM AUTHOR]

Background: Restoration of carious primary molars is still a major concern while treating the young children that too in deep carious lesion which extends below the cemento-enamel junction (CEJ) where pulp protection and achieving adequate marginal seal are very important to prevent secondary caries. The needs were met with the development of new materials. One such of new bioactive material is tricalcium silicate-based restorative material (Biodentine), recommended for restoring deep lesions. Aim: To evaluate and compare shear bond strength and microleakage of tricalcium silicate-based restorative material (Biodentine) and glass ionomer cement (Fuji IX GP) in primary and permanent teeth. Materials and Methods: Occlusal surface of crowns were ground flat. PVC molds were stabilized over flat dentin surface and filled with tricalcium silicate-based restorative material (Biodentine)/glass ionomer cement (Fuji IX GP) according to group ascertained. Shear bond strength was evaluated using universal testing machine (INSTRON). Standardized Class II cavities were prepared on both primary and permanent teeth, and then restored with tricalcium silicate-based restorative material (Biodentine)/glass ionomer cement (Fuji IX GP) according to group ascertained, over which composite resin material was restored using an open sandwich technique. Microleakage was assessed using dye penetration. Microleakage was examined using a stereomicroscope. Results: Results showed that glass ionomer cement (Fuji IX GP) exhibited better shear bond strength than tricalcium silicate-based restorative material (Biodentine). Mean microleakage score for glass ionomer cement (Fuji IX GP) in permanent teeth was 1.52 and for primary teeth was 1.56. The mean microleakage for tricalcium silicate-based restorative material (Biodentine) in permanent teeth was 0.76 and for primary teeth was 0.60. Glass ionomer cement (Fuji IX GP) exhibited more microleakage than tricalcium silicate-based restorative material (Biodentine), which was statistically significant both in permanent (P = 0.02) and primary (P = 0.006) teeth. Conclusion: Shear bond strength of glass ionomer cement (Fuji IX GP) is greater than tricalcium silicate-based restorative material (Biodentine) in both primary and permanent teeth. Tricalcium silicate-based restorative material (Biodentine) exhibited less microleakage compared to glass ionomer cement (Fuji IX GP) in both primary and permanent molars. [ABSTRACT FROM AUTHOR]

PURPOSE. Bonding agents (BA) are the crucial weak link of composite restorations. Since the commercial materials' compositions are not disclosed, studies to formulize the optimum ratios of different components are of value. The aim of this study was to find a proper formula of BAs. MATERIALS AND METHODS. This explorative experimental in vitro study was composed of 4 different sets of extensive experiments. A commercial BA and 7 experimental formulas were compared in terms of degree of conversion (5 experimental formulas), shear bond strength, mode of failure, and microleakage (3 experimental formulas). Statistical analyses were performed (α=.05). The DC of selected formula was tested one year later. RESULTS. The two-way ANOVA indicated a significant difference between the shear bond strength (SBS) of two tissues (dentin vs. enamel, P=.0001) in a way that dentinal bonds were weaker. However, there was no difference between the four materials (P=.283). The adhesive mode of failure was predominant in all groups. No differences between the microleakage of the four materials at occlusal (P=.788) or gingival (P=.508) sites were detected (Kruskal-Wallis). The Mann-Whitney U test showed a significant difference between the microleakage of all materials (3 experimental formulas and a commercial material) together at the occlusal site versus the gingival site (P=.041). CONCLUSION. A formula with 62% bisphenol A-glycidyl methacrylate (Bis-GMA), 37% hydroxy ethyl methacrylate (HEMA), 0.3% camphorquinone (CQ), and 0.7% dimethyl-para-toluidine (DMPT) seems a proper formula for mass production. The microleakage and SBS might be respectively higher and lower on dentin compared to enamel. [ABSTRACT FROM AUTHOR]

This study aimed to compare the effects of ethylenediaminetetraacetic acid (EDTA) and maleic acid (MA) on the sealing ability of various root canal sealers. Eighty root canals were instrumented and irrigated with either EDTA or MA. They were divided into eight experimental groups and obturated as follows: Group 1: MA + Hybrid Root SEAL/gutta-percha. Group 2: EDTA + Hybrid Root SEAL/gutta-percha. Group 3: MA + iRoot SP/gutta-percha. Group 4: EDTA + iRoot SP/gutta-percha. Group 5: MA + EndoREZ/EndoREZ points. Group 6: EDTA + EndoREZ/EndoREZ points. Group 7: MA + AH Plus/gutta-percha. Group 8: EDTA + AH Plus/gutta-percha. Another ten roots were used as negative and positive controls. The microleakage of each sample was measured at 2-min intervals for 8 min using the fluid filtration method. Data were statistically analyzed with one-way ANOVA, post-hoc Tukey, and paired-samples t tests. The minimum microleakage values were obtained from the teeth obturated with AH Plus and EndoREZ selaers (p < 0.001). The samples with Hybrid Root SEAL showed the maximum leakage (p < 0.001). There were significant differences between the groups irrigated with MA or EDTA in terms of microleakage (p < 0.05). Use of MA resulted in higher microleakage values compared with those using EDTA. The type of final irrigation solution seems to influence the postobturation apical seal. Use of AH Plus and EndoREZ sealers showed better sealing ability compared with IRoot SP and Hybrid Root SEAL. [ABSTRACT FROM AUTHOR]

Aim: The aim was to compare the microleakage of resin composite bonded with different adhesive systems in class-II cavities at enamel or dentine margins.Material and methods: 60 extracted human molar teeth received slot cavity preparations on mesial and distal surfaces (mesial cervical margin was prepared in enamel and distal in dentine). They were randomly divided into five groups (n = 12) according to the adhesive system: Group-A: Silorane Bond (S), Group-B: Adper Single Bond 2 (SB), Group-C: Clearfil SE Bond (CSE), Group-D: Single Bond Universal (USel) (selective etch-and-rinse), Group-E: Single Bond Universal (USE) (all-in-one). The preparations were restored using the same resin composite (Filtek Ultimate) except Group A which was restored by Silorane composite. The teeth were thermocycled, immersed in dye, sectioned, and dye penetration was evaluated quantitatively using image analysis. The data were analyzed using the two-way analysis of variance and Bonferroni test.Results: In all groups, there was no statistically significant difference between enamel margins at occlusal and gingival sites (p > 0.05). The statistical difference between Group-A (S) and Group-B (SB) was significant at all margins. Group-B (SB) presented the greatest microleakage amounts at all margins and the highest scores were obtained in the dentine. Likewise, SB demonstrated statistically significant differences between dentine and enamel margins (occlusal and gingival)(p < 0.05).Conclusion: All adhesive systems showed similar microleakage values between enamel margins in occlusal and gingival regions. However, when the gingival margin is located in the dentine, etch&rinse adhesive systems may not be a choice in terms of microleakage prevention. [ABSTRACT FROM AUTHOR]