Silicone negative replicas of dentine islands exposed by occlusal attrition were examined on extracted human teeth using the scanning electron microscope. Because the details of the dentinal tubules were reproducible on the silicone impression, the replication technique was applied in vivo to occlusal attrition to demonstrate patent dentinal tubules in cases with symptomatic exposed dentine islands. using this replication technique, it should be possible to monitor the effect of the therapeutic management of symptomatic tooth attrition on dentinal tubule closure.