Microplastics (MPs), synthetic polymers with particles <5 mm, can originate from primary sources like microbeads and secondary sources from the degradation of larger plastics. They can enter the body through inhalation, ingestion, and topical application. Recent studies have detected MPs in saliva, with significant implications for oral health, including their potential role in oral diseases and increased viscosity of saliva linked to higher MP concentrations. Few studies have found that the presence of MPs in saliva and sputum, with a concentration of MPs in saliva reported to the level of the total number of microplastics, was 39.5 particles/10 ml. The presence of MPs in saliva intrigues their role in oral diseases and the functions of saliva. Few pieces of evidence have reported that MPs increase the composition and rheological properties of saliva. For example, a study by Przekop et al found that the viscosity of saliva is high in individuals with high concentrations of MPs. MPs may also support biofilm formation and contribute to periodontal disease. Despite confirmed presence in various body parts, research on the quantity and effects of MPs in saliva and oral biofilms is limited. The proposed study aims to investigate the nature and abundance of MPs in oral biofilms, which will inform public health policies and raise awareness about the possible health risks associated with MPs, particularly concerning periodontal disease.