脱水症状が歯の色に及ぼす臨床的影響：どのくらいの量、どのくらいの期間？

Clinical effects of dehydration on tooth color: How much and how long?

• Hüseyin Hatırlı
• Emine Şirin Karaarslan
• Bilal Yaşa
• Enes Kılıç
• Ayla Yaylacı

抄録

目的:

脱水症状が歯の色に及ぼす影響を評価し、30分後または24時間後に歯の色がベースラインに戻るかどうかを判断する。

OBJECTIVE: To evaluate effects of dehydration on tooth color determine whether color returns to baseline after 30 min or 24 h.

材料と方法:

上顎中切歯と上顎側切歯を有する30名の被験者を対象とした．分光光度計（SpectroShade Micro）を用いて，ベースライン時，脱水後10分，20分，30分，および水分補給後30分と24時間後に，色の測定を行った。色差の算出にはCIEDE2000のカラーパラメーターを用いた。データは反復測定分散分析（ANOVA）によって経時的な色の変化を分析し，ANOVA後の比較にはBonferroni-Tukey検定を用いた（P<.05）。

MATERIALS AND METHODS: Thirty participants with intact maxillary central and lateral incisors were recruited for the study. Color measurements were performed with a spectrophotometer (SpectroShade Micro) at baseline and at 10, 20, and 30 min of dehydration, as well as 30 min and 24 h of rehydration. CIEDE2000 color parameters were used to calculate color difference. The data were analyzed for color changes over time by repeated-measures analysis of variance (ANOVA), and the Bonferroni-Tukey test was used for post-ANOVA comparisons (P < .05).

結果:

脱水30分後，すべての歯が知覚閾値(ΔE=0.8)を超え，85%の歯が受容閾値(ΔE=1.8)を超えていた．水分補給30分後，78.3%の歯が知覚閾値を超え，31.6%の歯が許容閾値を超えた．水分補給24時間後には，99.2%の歯が知覚閾値以下となり，90%の値が知覚閾値以下となった．

RESULTS: After 30 min of dehydration, all the tested teeth were above the perceptibility threshold (ΔE = 0.8), and 85% of the teeth were above the acceptability threshold (ΔE = 1.8). After 30 min of rehydration, 78.3% of the tested teeth were above the perceptibility threshold, and 31.6% of the teeth were above the acceptability threshold. After 24 h of rehydration, 99.2% of the teeth were below the acceptability threshold, and 90% of the values were below the perceptibility threshold.

結論:

30分間の歯の脱水は，臨床的に有意な色の変化をもたらす可能性がある．24時間の補水期間を経て、信頼性の高い色調評価が可能となる。

CONCLUSIONS: Thirty-minute tooth dehydration can result in a clinically significant color change. After a 24-h rehydration period, reliable color assessment can be performed.

臨床的意義:

歯の脱水は有意な色調変化を引き起こすため、審美修復や歯の漂白を行う際には、歯の水分補給後に最終的な色調の評価や臨床的成功を考慮する必要がある。

CLINICAL SIGNIFICANCE: Tooth dehydration causes significant color change, thus assessment of final color or clinical success should be considered after tooth rehydration for esthetic restorations and tooth bleaching.

© 2020 Wiley Periodicals LLC.