Reimposing The Consequences Of Outward Fit Of Wax Patterns For The Success Of Restoration By Metal Ceramic Crown

Background: For the success of the restoration by metal crown, the appropriate marginal fit is vital. Small gaps in the margins improve longevity and clinical outcomes of the restoration due to fewer cement washouts and less irritation to the gingiva.

Aim: The present study was conducted to assess the effect of die lubricant use on the marginal fit of wax patterns.

Methods: Tooth preparation for an ivorine tooth was done to receive a full coverage metal-ceramic restoration with a shoulder finish line of 360°. Tooth duplication was done 42 times with additional silicone. They were divided into 2 groups of 21 subjects each where Group I were fabricated using die lubricant and Group II without die lubricant. The marginal fit was then assured with a stereomicroscope, and the readings were tabulated for comparison of marginal fit for Group I and II. Mean gap was also assessed for Group I die lubricant and Group II without die lubricant.

Results: Mean values of gap without die lubricant were highest on the buccal surface which was 45.8µ and by the distal surface where it was 37.9µ. For mean difference of the gaps in two groups, significantly higher values were seen for group I at all the surfaces (p>0.05).

Conclusion: The present study concludes that die lubricant has a definitive effect on the marginal fit of the wax pattern, which, in the later phases can be duplicated in the casting.