The purpose of this investigation was to examine the effects of thermocycling upon the compressive strength and abrasive wear resistance of three commercial composites Fulfil®, P‐50® and Herculite‐XR®. Specimens of each material were divided into five treatment groups comprising a control, and four different cycling and storage regimes. Tests for compressive strength and wear resistance were carried out. Prior to testing all specimens were stored in distilled water for 1 week. Three groups were stored at a temperature of 37°C and the remaining two at 60°C. Thereafter all groups that were thermocycled were subjected to 750 cycles of a thermocycling regime consisting of the cycle ACAB where A and B represent the fixed temperatures of 37°C and 5°C, and C, depending upon the treatment group, either 50°C or 60°C. One‐way analyses of variance upon the compressive strength and wear factor data following the treatments highlighted significant differences in the mean compressive strength for all materials (Fulfil (P < 0.05), P‐50 and Herculite‐XR (P < 0.01)) and in the wear factor values for only Fulfil and P‐50 (P < 0.001). Surprisingly, thermocycling P‐50 with an upper temperature limit of 50°C had catastrophic consequences upon the measured properties. It is concluded that some of the observed behaviour may have potentially detrimental consequences upon the long‐term clinical durability of the materials tested.
|Number of pages||11|
|Journal||Journal of Oral Rehabilitation|
|Publication status||Published - Sep 1994|