Dentosphere : World of Dentistry

# After packing acrylic resin into the denture flasks, one should wait to cure the resin to: A. Assure full flow of acrylic into the denture mold B. Allow the monomer to reach all acrylic polymer C. Allow for pressure to be equalized between the acrylic and flask D. Make sure temperature equilibrium exists between the flask and acrylic  The correct answer is D. Make sure temperature equilibrium exists between the flask and acrylic Allowing the dental flask packed with acrylic to remain under the bench press until equilibrium in temperature is achieved will give enough time for the acrylic to achieve better monomer-polymer interaction and create stronger chemical bond. The curing of resin should be uniformly completed to lessen any chances of distortion before and during the time the flask is immersed in a water bath.  

# When fabricating dentures, what would be the most likely outcome if the lab compressed/packed the acrylic during the rubbery stage? A. Higher porosity than normal B. A lot of extra resin being attached to the denture that will take a long time to trim C. Incomplete picking up of anatomical details D. The denture would have an increased VDO  The correct answer is C. Incomplete picking up of anatomical details Packing and compressing acrylic during denture fabrication should be done in its doughy stage. The doughy stage is the ideal for packing acrylic resin because it is the moment when acrylic is most packable and workable. The rubbery stage of acrylic denotes the start of the setting when heat is released from the setting acrylic. Rubbery acrylic also has a tendency to revert back to its original position regardless of the forces applied to it during packing, resulting in incomplete packing. VDO (Vertical Dimension of Occlusion) is synonymous with OVD (Occlusal Vertical Dimensio...

# Which of the following is associated with a flabby maxillary anterior ridge under a complete denture? A. Retained mandibular anterior teeth B. A "V" shaped ridge C. A "U" shaped ridge D. A patient with Class Il occlusion E. Osteoporosis  The correct answer is A. Retained mandibular anterior teeth. Combination syndrome is a condition that usually occurs when retained mandibular anterior teeth opposes a maxillary complete denture. In combination syndrome, the anterior aspect of upper maxillary ridge becomes highly resorbed and flabby due to the biting force against its natural tooth antagonist. Since the occlusal force of a natural tooth is stronger than the force of a denture supported by an alveolar ridge, the area under pressure will exhibit higher resorption pattern than the rest of the denture.