Clinical performance and margin analysis of ariston pHc versus Solitaire I as posterior restorations after 1 year

The resin composite Ariston pHc (pHc means pH control) was introduced as an alternative for fast amalgam replacement. The aim of the present study was to evaluate clinically the behaviour of this non-bonded resin composite material, promising the release of fluoride, calcium, and hydroxy ions, in comparison to a bonded resin composite (Solitaire I) in class I and II cavities. Ninety-nine cavities in 31 patients were restored in a controlled prospective clinical study. Fifty fillings were placed with Ariston pHc as per the manufacturer's instructions, i.e. neither with enamel etching nor with the use of rubber dam. The same patients received 49 Solitaire I restorations totally bonded with Solidbond using rubber dam. At baseline, after 6 months, and after 12 months, two investigators given the same instructions examined the restorations, according to modified USPHS codes and criteria. Forty selected restorations (20 Ariston, 20 Solitaire) were additionally analysed via replicas, using a stereo light microscope (SV 11, Zeiss, Germany) at 130x magnification. After 12 months, 95 restorations were rated clinically acceptable (6% failure rate for Ariston pHc; 2% for Solitaire). Statistically significant differences were computed for both materials regarding the criterion "filling integrity". Further statistically significant deterioration for Ariston pHc between the three evaluations has been detected for the criteria "tooth integrity" (enamel cracks) and "marginal adaptation" (gap formation/Friedman 2-way ANOVA; p<0.05). With Ariston the criterion "hypersensitivity" also increased significantly after 1 year in comparison to Solitaire. The microscopic margin analysis revealed significantly increasing marginal deficiencies over time for both materials regarding the criteria "perfect margin", "gap formation", and "negative step" (P<0.05; Friedman 2-way ANOVA).