Evaluation of the Sealing Ability of Direct versus Direct-Indirect Veneer Techniques: An In Vitro Study

Backgrounds. Marginal discoloration, microleakage, wear, and marginal fractures are all prevalent problems with composite veneers, and this scenario leads the esthetic outcome to deteriorate with time, resulting in patient discontent. Aim of the Study. The study’s goal was to determine the marginal sealing ability of composite laminate veneers when employing two types of veneer techniques: direct and direct-indirect veneers, as well as two types of composite resin: nanohybrid and microfilled composite resin restorations, using dye penetration method. Materials and Methods. In this study, forty extracted human teeth were utilized. Following a standardized veneer preparation on the labial surface of the teeth, they were separated into two groups of 20 teeth each, using the following composite application techniques: group A: direct veneers and group B: direct-indirect veneers. Following that, each major group was separated into two subgroups of ten teeth each, based on the type of composite employed: subgroup 1 used nanohybrid composite resin, while subgroup 2 used microfilled composite resin. All of the samples were kept in distilled water, thermocycled, and soaked in 2% basic fuchsine dye. These specimens were sectioned and examined under a stereomicroscope for dye penetration at the gingival margin. The data was analyzed using independent T -tests using SPSS 22. Result. Using direct-indirect veneer technique with nanohybrid composite resin material resulted in the most negligible dye penetration at the gingival margin, while using direct veneer technique with microfilled composite resin material resulted in the maximum dye penetration. For both composite materials, gingival microleakage was lower when using the direct-indirect veneer technique than when using the direct technique, and the difference was statistically significant ( P < 0.05 ). In both techniques, gingival microleakage was lower with nanohybrid composite than with microfilled composite, and the difference was statistically highly significant ( P = 0.001 ). Conclusion. The sealing ability of the gingival margin of tooth/composite interface is better when applying direct-indirect veneer technique with nanohybrid composite resin than that of direct veneer technique with microfilled composite resin material.

Comparison of Root End Sealing Ability of Three Retrograde Filling Materials in Teeth with Root Apices Resected at 90° using Dye Penetration Method under Fluorescent Microscope: An In-vitro Study

Background: Inadequate seal at the apex is the substantial cause for surgical endodontic dissatisfaction. The retrograde filling material which is used should prevent the egress of potential contaminants into periradicular tissue. Objectives: To evaluate the ability of MTA Angelus, Zirconomer and Bioactive bone cement to seal the root end as retrograde filling material; and to compare root end sealing ability of these three different retrograde filling materials with apices resected at 900 angles using dye penetration method under fluorescent microscope. Methodology: Thirty six extracted upper anterior teeth are to be cut horizontally at the CEJ. After following the standard protocols of, “cleaning, shaping and obturation” with gutta percha and “AH Plus sealer”, the samples will be resected 3mm at the apical end at 90 degree angle along the long axis of the tooth with the help of diamond disc. A root end cavity of depth 3mm will be made with Diamond coated ultrasonic surgical tip S12 90 ND. The teeth will be randomly categorized in 3 groups: Group 1: MTA angelus; Group 2: Zirconomer; Group 3: Bioactive Bone Cement. Following which the roots to be coated with nail varnish except the tip. Each material will be compressed in the root end cavity with the help of small pluggers. All the samples which are retrofilled will be kept in acrydine orange for a duration of 24 hours, following which cleaning & bucco-lingual sectioning(vertical) will be done. Fluorescent microscope will be used for observation of sectioned root samples. Expected Results: Bioactive bone cement is expected to have better sealing ability of the retrograde cavity preparation with minimal or no microleakage followed by MTA Angelus and then Zirconomer. Conclusion: If this study proves correct, this would be helpful for the clinicians to choose better and the most efficient retrograde filling material with best sealing ability and minimal microleakage in a retrograde preparation which will aid in success of the root canal treatment further resolving the infection.

Sealing Efficiency of MTA, Accelerated MTA, Biodentine and RMGIC as Retrograde Filling Materials

Summary Background/Aim: This in-vitro study evaluated the apical-sealing ability of MTA, MTA+10% CaCl2, Biodentine™ and RMGIC when used as retrograde material. Material and Methods: A total of 80 single-rooted bovine incisors were decoronated, instrumented, and divided into 4 groups according to retrograde material, as follows: Group 1: MTA (ProRoot MTA, Dentsply); Group 2: MTA (ProRoot MTA, Dentsply) + 10% CaCl2; Group 3: Biodentine (Biodentine®, Septodont); Group 4: RMGIC (Nova Glass -LC, Imicryl). Root surfaces were isolated with nail polish, and teeth were immersed in 2% methylene blue dye at 37°C for 48 h. The extent of dye penetration (mm) was measured under a stereomicroscope. Results: RMGIC had the highest mean-rank dye penetration score (MP=49.05), followed by MTA (MP=43.65), Biodentine (35.95) and MTA+CaCl2 (MP=33.35). The results of paired comparison tests found the mean microleakage value of MTA+10% CaCl2 and Biodentine (Group 3) to be significantly lower than that of RMGIC (respectively; p=0,020, p=0,019). No significant difference was found in the other group comparisons (p> 0.05). Conclusions: These results suggest that the addition of an accelerator to MTA may reduce microleakage following endodontic surgery. Biodentine can be used as an alternative to MTA on retrograde obturation.

An Evaluation on Sealing Ability of Calcium Silicate-Based Cements and Glass Ionomer Cement as Perforation Repair Materials

Aims: The study evaluated the sealing ability of Biodentine, MTA Repair HP, and Glass ionomer cement as perforation repair materials by using a Stereomicroscopic analysis. Study Design: Experimental in vitro study Methodology: The access cavity was prepared on 45 samples of maxillary and mandibular teeth with a perforation of the standardized diameter of a No. 2 round bur at the bottom of the pulp chamber. All 45 samples were divided into three different experimental groups of 15 samples each. Group A (n=15), Group B (n=15) and Group C (n=15). The furcation repairs of the samples in groups A, B and C were carried out using Biodentine, MTA Repair HP and glass ionomer cement respectively. All sealed furcation perforation samples were stored at room temperature for 24 hours. Two layers of nail varnish were coated on all the surfaces to avoid dye penetration except for 2 mm around the area of the perforation site. After complete drying, all specimens were separately soaked in 2% methylene blue solution for 48 hours, cleaned with water and dried for 24 hours. They were sectioned buccolingually. The perforation wall of the sectioned sample with the greatest dye penetration was selected for microleakage analysis. Results: The collected data from the three experimental groups were subjected to statistical analysis using one-way analysis of variance and Tukey's post hoc test for multiple comparisons of mean differences in dye penetration. The Biodentine group had the significantly lowest dye penetration length compared with the MTA Repair HP and glass ionomer cement groups (P<0.001). Conclusion: Biodentine showed better sealing ability as a repair material for furcation perforations compared to the other two materials.

Efficacy of Different Tooth Lining Materials on Marginal Seal of Composite Restorations Extended upto Root Surface of the Tooth- Systematic Review

Introduction: Microleakage is a major concern in composite restorations, especially with margins located on dentin or cementum of the tooth. This study aimed to review the available literature investigating in vitro the efficacy of different tooth lining materials on the marginal seal of composite restorations extended below the Cemento-Enamel Junction (CEJ) of the tooth. Materials and Methods: Different combinations of the review terms were used to electronically search PubMed, Google Scholar, Cochrane Library, and Ebscohost databases for the last fifteen years. The records were initially screened for relevancy based on title and abstract. Articles that seemed to meet the criteria for inclusion were selected for full-text assessment. Studies deemed eligible were in vitro studies conducted on human teeth with cavities extending below the CEJ and restored using different tooth lining materials under the composite restorations.Every included study was evaluated using the Cochrane risk of bias assessment tool. Results: The initial search identified 619 publications. After removing duplicated records, the remaining 421 records are screened at the level of titles and abstracts to meet our inclusion criteria. 62 records were designated for full-text methodological assessment, and 15 studies were found eligible for qualitative synthesis. The sealing ability of different tooth lining materials under composite restorations was investigated in the chosen studies, with varying outcomes. Microleakage in the tooth restorations was determined by examining the extent of dye penetration under a microscope. Conclusion: Despite the reports of less dye penetration with specific tooth liners in some in-vitro studies, there is no consistent evidence supporting that such tooth liners could reduce microleakage in composite restorations of the tooth.

Comparing the Ability of Various Resin-Based Composites and Techniques to Seal Margins in Class-II Cavities

Background: Resin-based composites (RBCs) provide excellent esthetics but the marginal micro-leakage in the proximal cavities remains a major concern. The aim of the present study was to assess the ability of various dental RBCs and techniques utilized for sealing deep dentin margin in class-II cavities. Methods: Box-cavities (class-II) on the distal and mesial surfaces of extracted (premolar) teeth were prepared with a gingival margin placed 1mm apical to the cemento-enamel junction. Teeth with prepared class II cavities were randomly divided into four study groups according to the type of restorative materials (conventional RBC; bulk-fill RBC; conventional RBC lined with flowable RBC and conventional RBC lined with resin-modified glass-ionomer-cement (GIC) as open sandwich-technique). Each group was further subdivided into a total-etch subgroup in which a separate etching step was performed before applying the bonding agent and a self-etch subgroup in which a self-etch adhesive system was used (n = 10). For each group, cavities were restored using the respective restorative materials and techniques, subjected to 1000 thermocycles, and placed in the methylene-blue dye. The specimen teeth were sectioned for further microscopic examination for micro-leakage. Results: The least dye penetration values were reported for group 4 (GIC) followed by the group Bulk-fill using the self-etch adhesive system (group 2b). The highest dye penetration was reported for the group Bulk-fill using the total-etch adhesive system (2a), followed by the group conventional RBC using the total-etch adhesive system). The total-etch adhesive system had significantly greater micro-leakage compared to the self-etch adhesive system (1a) (p = 0.026). Conclusions: The self-etch adhesive system significantly reduced the micro-leakage compared to the total-etch system. Bulk-fill RBC when bonded with the self-etch adhesive provided good marginal sealing ability comparable to open sandwich-technique using GIC.

A influência de diferentes cimentos de obturação de canal na infiltração apical

It is an "in vitro" study to evaluate the sealing ability of 3 root canal sealers using a dye leakage/clearing method. 40 lower incisors were instrumented by the step-back technique and divided into 4 groups. The teeth were filled with lateral condensation of guta-percha varying the root canal sealer. Fill Canal, Sealer 26, N-Rickert were tested and compared to the control group in which guttapercha cones with no seater were used. Linear dye penetration was measured after demineralizatÎon and clearing. Statistical analysÏs showed significant differences among the groups. The lowest leakage values were found in the Fill Canal group followed by the N-Rickert and the Sealer 26 groups.