Australian Dental Council (ADC) Test 2025 – 400 Free Practice Questions to Pass the Exam

The volume shrinkage of methyl methacrylate monomer during polymerization is a well-documented phenomenon in dental materials, specifically in the context of denture base materials and composite resins. When methyl methacrylate undergoes polymerization, the transformation from the liquid monomer to the solid polymer involves a change in molecular arrangement, leading to a decrease in the overall volume.

A shrinkage of around 21% is considered accurate for the polymerization of methyl methacrylate, which reflects the density change and the arrangement of the polymer chains after the reaction. This significant shrinkage is a critical consideration for dental professionals, as it can affect the fit and adaptation of restorations or prosthetic devices, potentially leading to clinical complications such as gaps or inadequate sealing.

Understanding this shrinkage factor is essential for practitioners crafting restorations and for material scientists designing new formulations to mitigate such volume changes, which can enhance the mechanical performance and longevity of dental materials.