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Effect of time on tooth dehydration and rehydration
Sama Suliman1, Taiseer A Sulaiman1, Vilhelm G Olafsson2
1Division of Operative Dentistry and Biomaterials, Department of Restorative Sciences, University of North Carolina School of Dentistry, Chapel Hill, North Carolina.
Summary
Tooth dehydration significantly impacts shade selection accuracy. Perform shade selection within the first minute of isolation before dehydration occurs for optimal esthetic results.
Area of Science:
- Dental materials science
- Esthetic dentistry
Background:
- Accurate tooth shade selection is crucial for successful esthetic dental restorations.
- Tooth dehydration during dental procedures can alter perceived color, potentially compromising shade matching.
Purpose of the Study:
- To quantify the time-dependent changes in tooth color due to dehydration.
- To assess the rehydration rate of teeth after isolation.
- To determine the impact of these changes on the accuracy of tooth shade selection.
Main Methods:
- Spectrophotometric color measurements were taken on 32 participants' teeth at various intervals during dehydration (1-15 min) and rehydration.
- Color differences (CIEDE2000) were calculated and compared to perceptibility (0.8) and acceptability (1.8) thresholds.
- Statistical analysis using ANOVA and Tukey tests was employed.
Main Results:
- Significant tooth color changes exceeding the perceptibility threshold occurred within the first minute of dehydration.
- After 15 minutes of dehydration, 87% of teeth exceeded the perceptibility threshold and 72% exceeded the acceptability threshold.
- After 15 minutes of rehydration, 90% of teeth remained beyond the perceptibility threshold, indicating incomplete color recovery.
Conclusions:
- Tooth dehydration significantly alters color, negatively impacting shade selection accuracy.
- Shade selection must be performed within the first minute of isolation, before substantial dehydration occurs.
- Teeth do not fully rehydrate within 15 minutes post-isolation, further complicating shade matching if delayed.
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