# Comparative Evaluation of Tear Strength of Two Platinum-Based Maxillofacial Silicone Materials: Siloczest LSR With and Without the Addition of 2.5% Zinc Oxide (ZnO) Nanoparticles and Technovent (m511)—An In Vitro Study

## TL;DR

This study compares the tear strength of two platinum-based silicones for facial prosthetics, finding that adding zinc oxide nanoparticles slightly reduces performance.

## Contribution

The study evaluates a new indigenous silicone material and tests the effect of zinc oxide nanoparticles on tear strength in maxillofacial applications.

## Key findings

- Siloczest LSR had significantly higher tear strength than Technovent M511.
- Adding 2.5% ZnO nanoparticles reduced tear strength slightly in Siloczest LSR.
- Zinc oxide nanoparticles did not reinforce the silicone material effectively.

## Abstract

The present study aims to evaluate and compare the tear strength of an indigenous platinum-based maxillofacial silicone material (Siloczest LSR [Liquid Silicone Rubber]) with and without the incorporation of 2%–2.5% zinc oxide nanoparticles, using an imported platinum-based silicone material (Technovent M511) as the benchmark control.

Sixty-six unnicked 90° angle specimens (ASTM D624 [American Society for Material and Testing)) were fabricated and divided into three groups: Group A—Siloczest LSR without zinc oxide nanoparticles; Group B—Siloczest LSR with 2.5% zinc oxide nanoparticles; and Group C (control)—Technovent M511. Tear strength was evaluated using a Universal Testing Machine (UTM), and results were statistically analysed to compare the performance of the materials.

Siloczest LSR showed significantly higher tear strength (22.64 N/mm) than Technovent (10.08 N/mm, p < 0.001). The addition of 2.5% ZnO nanoparticles reduced tear strength to 20.54 N/mm (p < 0.05), indicating no reinforcement benefit.

Siloczest LSR, an indigenous platinum-based maxillofacial silicone, exhibited higher tear strength than the imported Technovent material, supporting its potential use in clinical prosthetic applications as a cost-effective maxillofacial material. However, the addition of 2.5% zinc oxide nanoparticles did not improve tear strength and led to a slight reduction. These results highlight the need for further investigation into nanoparticle concentration and dispersion methods to optimize reinforcement without compromising the material's mechanical integrity and clinical validation.