Abstract :
Cobalt chromium alloys is an essential alloys in dentistry and mostly used to fabricate rigid and strong denture base. Yet, dynamic oral saliva pH may cause the alloys to corrode and release toxic cobalt and chromium ions in the oral cavity. Surface modifications like silver coating is known to reduce the ion release in physiological environment. But its effect on different saliva pH is still yet unknown. This research examine the effect of protective silver coating and saliva pH towards the toxic cobalt and chromium ion release from cobalt chromium alloys. Total of 24 pieces of cobalt cromium alloys samples were casted. Half were coated with 5 μm silver, and the remaining were not coated. Samples were grouped and immersed in artificial saliva (pH Value: 5, 7 and 9), incubated in 370C for 14 days. Data were analyzed using two ways ANOVA and LSD post hoc test (p<0.05). The highest amount of cobalt (0.480 ppm) and chromium (49.109 ppb) ion were released from uncoated alloys in pH 5. Yet, comparatively, the lowest amount of cobalt (0.240 ppm) and chromium (17.865 ppb) ion were released from silver coated alloys in pH 7. Statistics analysis showed a significant results (p<0.05) of silver coating and saliva pH effects on the release of cobalt and chromium ion of cobalt chromium alloys.