1.Which statement about polymethyl methacrylate (PMMA) is incorrect?
2.Why is gel form of etchant favored over liquid form?
3.At what temperature does benzoyl peroxide generate free radicals during the polymerization of acrylic resin?
4.What is the typical etching depth achieved after 30 seconds of applying orthophosphoric acid for bonding orthodontic brackets?
5.What is the standard polymer to monomer ratio used for packing polymethyl methacrylate resin?
6.What is the typical range of residual monomer content found in chemically cured resins?
7.What is the primary role of a dentin conditioner?
8.What is the term for the method of combining two or more distinct monomers, each possessing unique characteristics, to produce a polymer with tailored physical properties?
9.Why are cross-linking agents primarily added to denture acrylics?
10.What causes subsurface porosity in materials?
11.What defect is observed in a processed denture if the resin is packed during the sandy stage?
12.Which material is commonly incorporated as a filler in composite resin formulations?
13.What is a likely outcome of inadequate sealing of flasks when packing denture base resin?
14.What is the minimum energy output required for a quartz tungsten light cure device?
15.Which substance initiates the polymerization process of heat-cured methyl methacrylate?
16.During the processing of methyl methacrylate resin, if the flask is closed prematurely, where is porosity most likely to develop?
17.How do composite resins compare to acrylic materials in terms of their properties?
18.What is a likely consequence of inadequate flask closure when packing denture base resin?
19.What is the primary cause of subsurface porosity?
20.What defect is likely to appear in a denture if the resin is packed while in the sandy phase?