The nature of the remaining dentin surface following application of Carisolv solution.

PURPOSE: To evaluate the effect of Carisolv solution on the topography and surface hardness of dentin. METHODS: Two separate studies were carried out. Atomic force microscopy (AFM) was employed to visualize dentin surface topography on slices of previously extracted non-carious and carious teeth following the passive application of Carisolv gel for 30- and 60-second periods. A Wallace hardness instrument was used to measure the dentin surface hardness following active caries removal with Carisolv gel and the specially designed instruments. Conventional caries removal with dental burs and non-carious dentin acted as controls for the latter study. RESULTS: AFM revealed that the passive application of Carisolv gel resulted in smoother surfaces than observed on carious and non-carious dentin. There was a statistically significant difference between the mean hardness values for non-carious and Carisolv-treated dentin (P< 0.05). There was no statistically significant difference between the non-carious and bur-treated dentin nor the Carisolv and bur-treated dentin.

The effectiveness of four-cavity treatment systems in sealing amalgam restorations.

Amalgam does not bond to tooth tissue; therefore, restorations using such material are prone to leakage despite the deposition of corrosion products. This study evaluated the effectiveness of four cavity treatment systems placed in vivo in sealing restorations of amalgam. Four cavity treatment systems were investigated in this study: Cervitec, Gluma One Bond, Panavia 21 and Copaliner Dentin Varnish and Sealant. No cavity treatment was placed in an additional group to serve as a control. The teeth were extracted within 15 minutes of restoration placement. The specimens were thermocycled (5-55 +/- 2 degrees C, 500 cycles), immersed in a dye solution, sectioned and scored for leakage. Scanning electron microscopy also examined features of the tooth/restoration interfaces. There were statistically significant differences among the groups regarding leakage scores (p = 0.00). None of the materials tested consistently prevented leakage; however, use of Copaliner Dentin Varnish and Sealant resulted in less overall, occlusal and cervical microleakage than any other systems tested. Significantly more leakage was observed in relation to the cervical portions of the cavities (p = 0.00). No significant differences were identified between the leakage scores obtained for the buccal and palatal (lingual) cavities and the different tooth types (p = 0.52 and 0.83, respectively). A level of significance of 0.05 was selected in all cases. The benefits of the materials tested in this study need to be evaluated using robust, long-term clinical studies. Further work should continue to develop laboratory tests that predict the behavior and performance of cavity sealants in clinical service.

Microleakage of amalgam cavity treatment systems: an in vitro evaluation.

PURPOSE: to evaluate the effectiveness of four cavity treatment systems for their ability to seal standardized Class V restorations of amalgam. MATERIALS AND METHODS: The Celay copy-milling machine was used to prepare twenty-five standardized Class V cavities on the buccal and palatal surfaces of maxillary premolar teeth extracted for orthodontic purposes. The cavosurface margins lay entirely within enamel. Five cavity treatment test groups were employed prior to amalgam placement: Group 1, Cervitec; Group 2, Gluma One Bond; Group 3, Panavia 21; Group 4, Copaliner Dentin Varnish and Sealant and Group 5, Control. Following restoration placement, the teeth were aged at room temperature (25 +/- 2 degrees C) in tap water for 2 months. The specimens were subsequently thermocycled (500 cycles, 5 -55 +/- 2 degrees C), immersed in a dye solution, sectioned and scored for microleakage. Scanning electron microscopy was employed to examine features of the tooth/restoration interface. RESULTS: None of the materials tested consistently prevented microleakage. No statistically significant differences were identified between the groups with respect to the microleakage scores (P > 0.05). The gingival walls exhibited significantly more microleakage than the occlusal walls (P = 0.00). No significant differences were identified between the microleakage scores obtained for the buccal and palatal cavities. Scanning electron microscopy examination failed to demonstrate a consistent pattern of interfacial appearance, showing a combination of cohesive and adhesive failure within and between test groups.