In Vitro Evaluation of Contact Tightness and Marginal Overhang in Class II Primary Molar Restorations Restored with Different Matrix Systems.

Abstract

Aims and background: Matrix systems are essential for creating the best contacts in class II restorations. The objective of this study is to compare five different matrix systems in class II cavities in terms of proximal contact tightness and marginal overhang.

Materials and methods: A total of 50 standardized second primary model teeth with class II cavities were printed using a three-dimensional (3D) printer. They were divided into five groups (n = 10). Resin restorations were made in each group; each tooth was placed on the full teeth model; and the model was placed in the universal testing machine for proximal contact tightness measurement. The maximum friction force was measured by moving an ivory matrix band in the occlusal direction. Digital images were obtained from the interproximal area with a stereomicroscope. Marginal overhang values were obtained by subtracting the cavity borders from the restoration borders. Comparison of mean values between groups was analyzed statistically by the Kruskal-Wallis test. Cohen's effect sizes were calculated for each group analysis.

Results: There was no significant difference between matrix groups in terms of proximal contact tightness (p = 0.255). Marginal overhang values in restorations using Tofflemire were found to be significantly lower than Walser, Metafix, and Supercap. Omnimatrix was found to be significantly lower than Metafix and Supercap.

Conclusion: Among these five matrix systems, using the Tofflemire matrix can result in less overhang in primary molar restorations.

Clinical significance: Although various matrix systems are being developed in modern dentistry, it has been observed that the Tofflemire matrix is still reasonable in terms of material overhang.

How to cite this article: Yanar GN, Bodur CH, Yılmaz T. In Vitro Evaluation of Contact Tightness and Marginal Overhang in Class II Primary Molar Restorations Restored with Different Matrix Systems. Int J Clin Pediatr Dent 2025;18(7):814-819.