Nonresistance to closure and relative compression-resistance on setting are important factors in accurate recording of jaw relations. This study compared consistency, compressive stress at 1% strain and dimensional change to determine the accuracy of interocc1usal recording materials. Five kinds of materials were tested : Perfect VPS BITE(PV; Korea), Blu-Mousse(BM; U.S.A.), Ramitec(RA; Germany), Bosworth Superbite(SB; U.S.A.), Pattern Resin(PR; Japan). Consistency was measured with 10 samples of each brand, 5ml under 1330g loadings. Compression test was performed using Universal Testing Machine(Instron) at a rate of 10mm/min to the strain of l% to measure the compressive stress. Using Nissin dentiform, Vericheck(Denar) and Nikon measurescope centric occlusion without records(CORX), with records upon setting(CORO) and with records after 12 hrs(CORO12) were observed to measure the dimensional change.
Results were as follows :
1. The flow of BM was significantly higher than others and that of PV was the lowest(p<0.01).
2. The compressive stresses of PR and SB were extremely high compared with others. Among the elastomers those of BM and PV were significantly greater than RA(p<0.05).
3. The position changes of elastic recording materials were significantly smaller than nonelastic materials(p<0.05).
It was concluded that elastic interocclusal recording materials deviated less than nonelastic materials from their original positions and it seemed to be related more closely with consistency, compressive stress than with dimensional change of the material itself.
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