In recent years, metal oxide nanoparticles (MONPs) have experienced a growing trend in a wide range of industrial applications. Among them, silver nanoparticles (Ag-NPs) and titanium dioxide nanoparticles (TiO2 NPs) are by far the most used, in industry, agriculture, personal care products (PCPs). The unique properties of silver nanoparticles make them ideal for numerous technologies, including biomedical, materials, optical, and antimicrobial applications. Silver NPs have really been a future of dentistry. The continuing breakthroughs in the synthesis of TiO2 nanomaterials have brought new properties and new applications with improved performance. Titanium dioxide, apart from its numerous uses in the biomedical field, has also raised questions regarding its potential as an immunotoxic compound.