Ceramic inlays bonded with two adhesives after 4 years

Objective The aim of the present study was to clinically evaluate the effect of two different adhesive/resin composite combinations for luting of IPS Empress inlays. Methods Ninety-four IPS Empress restorations were placed in 31 patients in a controlled prospective clinical split-mouth study. The restorations were luted with EBS Multi/Compolute (3M Espe) or with Syntac/Variolink II low (Ivoclar Vivadent) without lining. At baseline and after 0.5, 1, 2, and 4 years, the ceramic restorations were examined according to modified USPHS codes and criteria. Results Two patients including four restorations missed the 4 years recall (drop out). After 4 years of clinical service, four restorations in two patients (three luted with Compolute, one with Variolink II) had to be replaced due to hypersensitivities, 90 inlays and onlays were acceptable (failure rate 4%; Kaplan–Meier survival analysis). Between the five recalls, a statistically significant deterioration was found for the criteria marginal adaptation and inlay fracture (Friedman 2-way ANOVA; p<0.05). Between the adhesives no statistical difference was found. At baseline, 95% of the restorations revealed luting composite overhangs. After 4 years, 55% of cases had overhangs and 38% showed marginal ditching. No differences were found for surface roughness, color matching, integrity tooth, proximal contact, hypersensitivity, and satisfaction (p>0.05). Conclusion For luting of ceramic inlays, no difference between the two luting systems was detectable. The overall failure rate after 4 years was 4%.