Barry M. Owens

Marginal Permeability of Self-etch and Total-etch Adhesive Systems

This study evaluated microleakage in vitro of self-etch and multi-step, total-etch adhesive systems. Ninety-six extracted non-carious human molars were randomly assigned to eight groups (n=12) and restored with different adhesive systems: Optibond Solo Plus, iBond, Adper Prompt L-Pop, Xeno III, Simplicity, Nano-Bond, Adper Scotchbond Multi-Purpose and Touch & Bond. Each group was treated following the manufacturers instructions. Class V cavities were prepared on the facial or lingual surfaces of each tooth with coronal margins in enamel and apical margins in cementum (dentin). The teeth were restored with Z-100 resin composite. After polishing with Sof-Lex disks, the teeth were thermocycled for 1000 cycles and coated with nail varnish to within 1.0 mm of the restoration. The teeth were stained in 1% methylene blue dye for 24 hours and sectioned from the facial to lingual surface. Dye penetration (microleakage) was examined with a 20x binocular microscope. Enamel and dentin margin leakage was scored on a 0 to 3 ordinal scale. Data were analyzed using Kruskal-Wallis Analysis of Variance and Mann-Whitney U tests. Comparison of the adhesive groups at the enamel margin revealed: 1) Adper Scotchbond Multi-Purpose exhibited significantly less leakage than the other adhesive groups (except iBond); 2) among the self-etch adhesive groups, iBond exhibited significantly less leakage than Nano-Bond and 3) the other adhesive groups clustered intermediately. In contrast, there were no significant differences among the adhesive groups when the dentin margin was evaluated. A Wilcoxin signed rank test showed significantly less leakage at the enamel margins compared to the dentin margins of the eight adhesive systems tested. All data were submitted to statistical analysis at p<0.05 level of significance.

Effect of single step adhesives on the marginal permeability of Class V resin composites.

This in vitro study evaluated the coronal and apical marginal microleakage of four self-etch, seventh generation adhesive systems. Sixty non-carious human molars were randomly assigned to four groups (n = 12). Class V cavities were prepared on the facial or lingual surface of each tooth with coronal margins in enamel and apical margins in cementum (dentin) at the cementoenamel junction. The preparations were restored using four self-etch adhesive systems (iBond, G-Bond, Xeno IV and Clearfil S3 Bond) and a control (no adhesive), followed by insertion of Gradia Direct microfilled hybrid resin composite. The teeth (specimens) were thermocycled 1,000 cycles, immersed in 1% methylene blue dye for 24 hours and invested in acrylic resin. The specimen blocks were then sectioned longitudinally, with dye penetration (microleakage) examined using a 20x binocular microscope. Coronal and apical margins were scored separately for microleakage using a 0-3 ordinal ranking system. Data were analyzed using non-parametric tests at a p < 0.05 level of significance. A comparison of adhesive and control groups at the coronal and apical margins revealed that significant (p < .0001) differences were exhibited. At the coronal margin, Xeno IV revealed significantly less leakage than the other adhesives, with Clearfil S3 Bond exhibiting significantly less leakage at the apical margin. Groups with no adhesive treatment (control) showed significantly greater leakage at both the coronal and apical margin locations. A Wilcoxon signed rank test showed no significant differences at the coronal compared to the apical margins of the four adhesive systems and control tested.

Alternative rubber dam isolation technique for the restoration of Class V cervical lesions.

This article describes an expedited, atraumatic technique of restoring cervical abrasion-erosion, abfraction or carious lesions using an alternative placement sequence of the dental rubber dam for adequate field isolation. As shown by this technique, the rubber dam retainer is modified and positioned on the tooth with subsequent placement of the dental dam material over theretainer and tooth. This technique saves time and provides good retraction of the gingival tissue and isolation of the cavity preparation from contamination (saliva, hemorrhage) that can potentially cause post-operative symptoms and possible restoration replacement.

Microleakage of Class I and II Composite Resin Restorations Using a Sonic-resin Placement System.

OBJECTIVES To determine microleakage of posterior Class I and II restorations using the SonicFill composite resin system. METHODS AND MATERIALS Eighty previously extracted third molars were randomly assigned to four preparation/restoration groups (n=20): Group A: Class I preparations restored with SonicFill system/bulk fill; Group B: Class II preparations restored with SonicFill system/bulk fill; Group C: Class I preparations restored with Herculite Ultra composite resin/incremental technique; and Group D: Class II preparations restored with Herculite Ultra composite resin/incremental technique. Class I preparations were approximately 3.0 mm in width buccolingually and 3.0 mm in depth. Class II preparations were approximately 3.0 mm in width buccolingually, 1.5 mm in axial depth, and 4.0 mm in gingival depth. In all groups, the enamel and dentin surfaces were conditioned with Kerr 37.5% phosphoric acid, followed by application of Optibond Solo Plus adhesive system. Following restoration, the specimens were thermocycled, immersed in methylene blue dye, and embedded in acrylic resin. Specimen blocks were sectioned in the mesiodistal direction, with marginal dye penetration (microleakage) examined using a 20× binocular microscope. Class I and II restoration microleakage was scored separately using a 0-3 ordinal ranking system. Statistical analyses were conducted using nonparametric testing at the p < 0.05 level of significance. RESULTS Significantly less microleakage was associated with both Class I restorative groups (A and C), SonicFill bulk fill and Herculite Ultra incremental fill, compared to the Class II restorative groups (B and D), SonicFill/bulk fill and Herculite Ultra/incremental fill. CONCLUSIONS According to the results of this study, the materials (SonicFill vs Herculite Ultra), C-factors, and insertion techniques (bulk vs incremental) did not appear to be significant influences with regard to marginal microleakage; however, the type of preparation cavity (Class I vs Class II) and the subsequent bonding surface (enamel vs dentin [cementum]) proved to be significant factors.