Application of the pin-hole marker measurement of the irregular silicone impression accuracy
Gong, Y.; Chen, J.; Li, Y.-k.; Wei, B.; Shen, G.
Shanghai Kou Qiang Yi Xue 21(3): 261-265
2012
ISSN/ISBN: 1006-7248 PMID: 22885483 Document Number: 658952
To investigate the feasibility of the pin-hole marker measurement of the irregular silicone dental impression accuracy. The metal model simulating abutment preparations had triangle-formed circular needles on the surface. Two silicone impressions were made by the metal model with the corresponding pin-hole markers. The dimensional change of the markers was evaluated by stereomicroscope. The records were output by the software which could simulate the centre of a circle to measure the displacement and dimensional accuracy. The outline of pin-hole marker was clear and shape was stable. Values of center coordinates were repeated well. The percentage of linear dimensional change of two impression samples was 0.023% and 0.042% at 48h respectively. Between two abutment preparations, the percentage of linear dimensional change of Zhermeck silicone impression increased 0.214% (45.1μm) at 1h and decreased 0.019% (4.0μm) at 48h while 3M silicone impression increased 0.087%(18.2μm) at 1h and decreased 0.09% (18.8μm) at 48h. The pin-hole marker measurement of the irregular silicone impression accuracy was feasible.