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Enamel micro-cracks produced around restorations with flowable composites.

Linlin Han·Akira Okamoto·Masayoshi Fukushima·Takashi Okiji
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Abstract

In this study, enamel micro-cracks produced around flowable composite restorations were observed using a stereomicroscope and a scanning confocal laser microscope (SCLM). The effects of polymerization shrinkage, mobility of composite and polishing period after filling on the incidence of marginal enamel micro-cracks were examined. Enamel micro-cracks were observed on all of the composite restorations when the restoration was polished immediately after filling. Enamel micro-cracks distributed approximately parallel to the cavity margin and located 0.01-0.3 mm from the restored cavity margin. The occurrence of enamel micro-cracks was higher in conventional hybrid composite restorations than in flowable composites, and when polished 15 minutes after filling (as compared to 24 hours after filling).

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Analysis of VarianceComposite ResinsDental EnamelDental Marginal AdaptationDental PolishingDental Restoration, PermanentDental Stress AnalysisHumansLightMaterials TestingMethacrylatesMicroscopy, ConfocalPhase TransitionPolymethacrylic AcidsViscosityComparative StudyJournal Article

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Linlin Han, Akira Okamoto, Masayoshi Fukushima, Takashi Okiji. 2005. Enamel micro-cracks produced around restorations with flowable composites.. https://doi.org/10.4012/dmj.24.83

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