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Three-year performance of a calcium-, fluoride-, and hydroxyl-ions-releasing resin composite

Secondary caries is the main reason for replacement of restorations in cross-sectional studies. To prevent demineralization, the use of ion-releasing materials has been suggested. The purpose of this study was to evaluate the durability of a new resin composite that releases calcium-, fluoride- and hydroxyl ions at low pH. Sixty-nine posterior restorations were placed in 36 patients and were evaluated at baseline, 6 months, 1, 2, and 3 years with slightly modified USPHS criteria. Postoperative sensitivity was observed in 2 teeth directly after placement and in another 8 teeth after 6-12 months. Absence of the use of an adhesive bonding technique explained the symptoms. A total of 26% failures was observed during the follow-up: 13 cusp fractures, 2 partial fractures of the resin composite, 1 secondary caries and 1 endodontic treatment due to prolonged sensitivity. The cusp fractures occurred during the second part of the follow-up and may be explained by expansion of the composite material due to water expansion and/or hydrolytic degradation of the alkaline glass filler. It can be concluded that the new ion-releasing resin composite showed, despite promising pH stabilizing properties, a clinically unacceptable failure rate.