New carbide finishing burs to reduce polishing efforts of light-cured restorations

Objective: To compare, under laboratory conditions, the efficacy of different polishing systems for various light-curing restorative materials. Method and Materials: Class 5 cavities were prepared in 65 human teeth and filled with 5 different light-curing restorative materials. To increase the number of samples, an extra 585 Class 5 cavities were made in resin disks and filled with the 5 different restorative materials. All restorations were polished with 13 polishing procedures commonly used in dental practice. The restoration surfaces were evaluated micromorphologically by means of SEM. A quantitative analysis of the polishing result was performed with the surface tester with waveline profilometry. The time required to achieve a polished surface was also measured. Results: Surfaces of all 5 restorative materials showed a satisfactory finish after treatment. SEM analysis and profilometry showed good surface qualities with large smooth, homogenous areas with low roughness. All polished surfaces were smoother than natural dental enamel. Sof-Lex, Super Snap, and Bush composite finished set 5430 systems showed the best areas with a smooth and homogenous surface. The extra effort required with several systems resulted in a smooth final restoration. Conclusion: The surface produced by the carbide finisher H134Q was rough, so it is useful for effective contouring of restorations. Application of the finishers H282K and H22ALGK led to a high share in good surface quality, which could be enhanced by using polishing paste as a final working step. The instruments H22GK and the systems One Gloss and Enhance were not recommendable. In comparison, the combination of H134Q and H22ALGK was effective, at the same time preserving tissue and saving time in finishing light-cured Class 5 restorations. The use of polishing paste as a final step is recommended. Keywords: carbide finishing bur, ergometry, light-cured restorations, polishing systems