Comparative evaluation of microleakage in Class II restorations using open vs. closed centripetal build-up techniques with different lining materials

The efficacy of lining materials in the reduction of microleakage in class II composite resin restoration using the sandwich technique: A stereomicroscopic study

Background

The sealing ability of different liners under composite restorations in the reduction of microleakage.

Aim

To evaluate the effects of three different liners in sandwich techniques on gingival microleakage of class II composite restorations.

Materials and Methods

Standardized Class II box cavities were prepared on forty premolar teeth and randomly divided into four groups, n = 10: Group A, no liner (control); Group B, Polofil NHT Flow; Group C, Ionolux; and Group D, Fuji VII. The etching, bonding, and process for restoring the whole remaining mass of the cavities with G-aenial composite were the same, with the sandwich material expectations. Dye penetration was evaluated using a stereomicroscope.

Statistical Analysis

Duncan's Post hoc analysis and Friedman's test.

Results

Group A showed the highest microleakage followed by Group D, Group C, and Group B.

Conclusion

Polofil NHT Flow seems to be a promising liner for gingivally deep class II cavities.

Pre-endodontic restoration of structurally compromised teeth: current concepts

Teeth that require endodontic treatment are often structurally compromised and this considerably complicates endodontic procedures. Therefore, pre-endodontic restoration is a key approach that dentists should consider for such teeth. This article discusses current concepts of pre-endodontic restoration, with a focus on adhesive restorative methods and surgical/orthodontic techniques, and provides a relevant decision-making flowchart.

Highlights the importance of pre-endodontic restoration for the predictability of endodontic treatment.

Discusses restorability aspects for structurally compromised teeth.

Reviews current restorative and surgical/orthodontic techniques for pre-endodontic restoration and provides a decision-making flowchart.

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.