INFLUENCE OF METAL VERSUS TRANSPARENT MATRICES ON PROXIMAL CONTACT TIGHTNESS OF CLASS II BULK-FILL COMPOSITE RESTORATIONS

Document Type : Original Article

Author

Associate Professor, Department of Operative Dentistry, Faculty of Dentistry, King Abdulaziz University, Jeddah, Saudi Arabia. Nahda University, Faculty of Dentistry, Conservative Dentistry Department, Beni Suef, Egypt

Abstract

Purpose: This study investigated the effect of metal versus transparent matrix systems on proximal contact tightness (PCT) of class II bulk-fill composite resin restorations.
Methods: 80 Ivorine teeth with standardized MO cavity preparations were randomly divided into 4 equal groups (n=20). Group1; sectional metal matrix, group2; pre-contoured circumferential metal matrix in a Tofflemire retainer, group3; conventional metal matrix in a Tofflemire retainer, and group4; Blue Cure-Thru transparent contoured matrix band. All matrices were combined with a separation ring and secured with wooden wedges. Cavity preparations were restored with bulk-fill composite resin; SonicFill 2 with the corresponding bonding system following manufacturer’s instructions. Composite material cured for 20s using Elipar S10 light curing unit. Teeth were restored in a clinically relevant situation using KaVo manikin head. After matrix and wedge removal, proximal contact tightness was measured using the Tooth Pressure Meter. Means were calculated and data were statistically-analyzed using ANOVA and Tukey’s test (p<.05).
Results: Means and standard deviation for proximal contact measurements were: 7.62 (.52), 4.01 (.74), 4.13 (.4) and 2.74 (.37) for groups 1, 2, 3 and 4 respectively. There was a statistical significant difference among all groups except between group2 and 3.
Conclusions: Under the conditions of this test, it can be concluded that: 1. Proper proximal contact tightness for bulk-fill posterior composite restorations could be produced by sectional metal matrix rather than transparent matrix. 2. Pre-contoured circumferential metal matrix produced the same proximal contact tightness as conventional metal matrix when both used with a separation ring.
Clinical Relevance Transparent matrices couldn’t be recommended for bulk-fill posterior com­posite restorations rather than metal matrices

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