COMPARATIVE EVALUATION OF COMPRESSIVE STRENGTH AND FLEXURAL STRENGTH OF NEWER POSTERIOR COMPOSITES: AN IN-VITRO STUDY.

Aim: The purpose of the study is to evaluate and compare compressive strength and flexural strength of newer posterior composites (Ceram X sphere tech one, Endure nano, Swiss tec) using Universal Testing Machine. Methodology: As per ISO standardisation 4049:2009 and ISO 9917-1:2007 for polymer based materials and powder/liquid acid-base cements respectively, 6x4mm custom mould was fabricated for preparing samples to analyse the compressive strength of the materials. A total of 30 samples were prepared and allocated into the main group ‘A’. It was further subdivided into four sub-groups, each containing ten samples, as follows: • Group A1: Pre-polymerised Nanoceramic nano composite (Ceram X sphere tech one, Densply Sirona, UK) • Group A2: Nano ceramic composite (Endure nano, Septodont, India) • Group A3: Micro-hybrid composite (Swiss Tech, Coltene). As per ISO standardisation 4049:2009 and ISO 9917-1:2007 for polymer based materials and powder/liquid acid-base cements respectively, 25x2x2mm custom mould was fabricated for preparing samples to analyse the flexural strength of the materials. A total of 30 samples were prepared and allocated into the main group ‘B’. It was further subdivided into four sub-groups, each containing ten samples, as follows: • Group B1: Pre-polymerised Nanoceramic nano composite (Ceram X sphere tech one, Densply Sirona, UK) • Group B2: Nano ceramic composite (Endure nano, Septodont, India) • Group B3: Micro-hybrid composite (Swiss Tech, Coltene). The compressive strength testing of the fabricated samples was performed with a Universal Testing Machine (Tec-Sol India) at a cross head speed of 0.5mm/min. For flexural strength, the fabricated samples were mounted on a 3-point bending test device and loaded in the Universal Testing Machine (Tec-Sol India) at a cross head speed of 1 mm/min. Results: The Nano hybrid composite (Endure Nano, Septodont) exhibits the highest compressive and flexural strength making it suitable for posterior restoration procedures. The pre-polymerised nano ceramic composites (Ceram X sphere Tech One, Densply sirona, UK) possess minimum compressive and flexural strength in this study, within the limitations of this study Conclusion: All the tested materials exhibited sufficient flexural and compressive strengths with Nano hybrid composite exhibiting significant higher physico-mechanical properties. [ABSTRACT FROM AUTHOR]