تأثیر ادهزیوهای توتال اچ و یونیورسال بر روی ریز نشت بین کامپوزیت و گلاس آینومر در ترمیم‌های ساندویچ کلاس II

Background and purpose: Microleakage is the most common cause of secondary caries and failure of restorations. The aim of this study was to evaluate the Microleakage between resin modified glass-ionomer (RMGI) and resin composite in sandwich restorations using different bonding agents. Materials and methods: Forty four premolars were used in this experimental study. Class II cavities were prepared  and the gingival margin placed 1 mm below cementoenamel junction. RMGI (Fuji II LC) was inserted on the gingival floor in 1 mm thickness and the teeth were divided into two groups. Group I: cavities were etched, rinsed and treated with a total etch adhesive (Adper single bond 2). Group II: An universal adhesive (Single bond universal) was applied in self etch mode. All cavities were then restored incrementally using resin composite (Filtek Z 250). To evaluate the microleakage, the samples were subjected to thermocycling (3000 cycles), immersed in methylene blue for 72 hours, and sectioned mesiodistally. The samples were subsequently observed under stereomicroscope. Mann-Whitney test was used to analyze the data (P<0.05). Results: The microleakage was significantly higher in Adper single bond 2 group (520.5±401.5µm) compared with that in single bond universal group (193±269.5µm). Conclusion: This study showed that application of  universal adhesive between RMGI and composite in self etch mode leads to lower microleakage compared with total etch adhesive in open sandwich restorations.