This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Dental
[{'content': 'Resin matrix system used in the composite shown below is: \nSelect and explain. \nA. Ormocers, B. POSS, C. Siloranes, D. Giomers', 'role': 'user'}, {'content': 'Answer: B \nExplanation: Polyhedral Oligomeric Silsesquioxane (POSS):\nPOSS molecules are 12-sided silicate cages produced from silane and functionalized to copolymerize with other monomers.\nPOSS is a molecule-sized hybrid organic-inorganic oligomeric compound that can disperse homogeneously in compatible monomers and become covalently incorporated into cross-linked networks upon curing. Like the ormocer-type materials, the silicate cage structures provide a reinforcing function, but filler particles must also be included to achieve the balance of mechanical and other properties required for adequate performance as dental composites.\nReference-Phillips’ Science of Dental Materials / Kenneth J. Anusavice - 11th Ed Pg:303', 'role': 'assistant'}]