Depth of Cure of Proximal Composite Restorations using a New Perforated Metal Matrix
Uniformed Services University of the Health Sciences Lackland AFB United States
Pagination or Media Count:
The purpose of this study was to compare the depth of cure of a class 2 preparation filled in bulk with composite and polymerized with tri-sited light curing using a new micro-windowed metal matrix compared to techniques using more traditional matrix systems. A divergent proximal box was prepared in an extracted human third molar. The cusp tips were flattened slightly and the preparation was lightly lubricated. A bi-tine ring V4 Ring, Triodent and three matrix types were placed ClearMetal micro-windowed metal matrix Triodent, Composi-Tight 3D Clearmatrix Garrison, and V3 Metal Tab-Matrix Triodent n10. SonicFill 2 Kerr and Herculite Ultra Kerr composites were placed in bulk and polymerized with a curing light from the occlusal 20-secs and from the buccal and lingual 10-secs. The V3 Metal matrix was removed before curing from the proximal following the manufacturers recommendations. Two additional groups were created with the V3 Metal matrix that were not removed and only cured from the occlusal, using both SonicFill 2 and Herculite Ultra. The composite specimens were removed from the tooth and stored for 24 hours at 37C. Knoop hardness was determined at one-mm increments at 0.5, 1, 2, 3, 4 and 5mm from the occlusal surface. Percent bottommaximum hardness ratios were determined based on maximum hardness measured at 0.5 mm from the occlusal surface for each composite. Data were analyzed with separate two-way ANOVAs and Tukeys post hoctests examining the effect of depth and matrix type or depth and curing mode per composite type on hardness ratios. For both SonicFill 2 and Herculite Ultra, significant differences were found based on depth, but not on type of matrix band. The use of the new perforated metal matrix bandClearMetal resulted in depth of cure that was not significantly different than the use of metalthat was removed or transparent matrix bands when using tri-sited light curing.
- Anatomy and Physiology
- Laminates and Composite Materials
- Properties of Metals and Alloys