Khalid Hussain, Fahim Anwar, Mikrza Khan Tareen, Muhammad Tariq.
Effect of marginal leakage around class II composite resin restorations.
Ann King Edward Med Uni Jan ;13(1):133-4.

The desire for improved esthetics have led to the appearance of "posterior composite resins" for occlusal restorations. Forty extracted permanent human molars and premolars of mesial or distal class II cavities were included. There was no leakage found at 58% and 89%. The lowest degree of leakage for all filling methods was found at the occlusal margin.

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