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': 'A male 45 years old wants his missing teeth to be replaced. Intraoral examination reveals Kennedy class 4 edentulous  maxillary arch. Impression is made using laminate technique.\nThe disadvantages of this technique are all except: \nSelect and explain. \nA. The bond between the two is not always sound, B. The higher viscosity of one displaces the other hydrocolloid during seating, C. The dimensional inaccuracy of the hydrocolloid limits its use to single units, D. Only the syringe material needs to be heated for this technique', 'role': 'user'}, {'content': 'Answer: D \nExplanation: LAMINATE TECHNIQUE (ALGINATE-AGAR METHOD)\nA modification of the traditional agar procedure is the combined agar-alginate technique. The agar in the tray is replaced with a mix of chilled alginate that bonds to the agar expressed from\xa0a\xa0syringe.\xa0 The\xa0alginate\xa0gels\xa0by\xa0a\xa0chemical\xa0reaction, whereas the agar gels by means of contact with the cool alginate rather than with the water circulating through the tray. Since it is the agar, not the alginate, that contacts the prepared teeth, maximal detail is reproduced. Because only the syringe material needs to be heated, equipment cost is lower and less preparation time is required.\xa0\nThe main disadvantages of this technique are as follows:\n\nThe bond between the agar and the alginate is not always sound.\nThe higher viscosity of the alginate material displaces the agar hydrocolloid during seating.\nThe dimensional inaccuracy of the alginate hydrocolloid\xa0limits\xa0its\xa0use\xa0to\xa0single\xa0units.\n\nReference:\xa0Phillips’ science of dental materials / Kenneth J. Anusavice, Chiayi Shen, H. Ralph Rawls.—12th ed. Page no 176', 'role': 'assistant'}]