Dental School, Department of Prosthetic Dentistry, University of Heidelberg, Heidelberg, Germany.
Section of Gerontopsychiatric Research, Department of Psychiatry, University of Heidelberg, Heidelberg, Germany.
J Esthet Restor Dent. 2017 Nov 12;29(6):459-463. doi: 10.1111/jerd.12334. Epub 2017 Aug 31.
To evaluate changes in tooth color for 2 age cohorts (younger cohort, YC: 1950-1952; older cohort, OC: 1930-1932) over a mean observation period of 8 years.
Sixty-one participants with 106 upper central incisors were subjected to baseline and follow-up examinations (YC: n = 46/OC: n = 15). International Commission on Illumination color coordinates of 1 or 2 unrestored test teeth for each participant were recorded by use of a spectrophotometer (VITA Easyshade 1) during both measurement times. Changes of color coordinates during the study period were evaluated by use of generalized linear mixed models with the variable "participant" as random effect. ΔE and E color differences were calculated between baseline and follow-up.
Significant changes in color coordinates were observed, with the exception of lightness in OC. The direction of the changes depended on the cohort. A decrease of lightness (value) was observed in YC (ΔL = 4.0; P < .001) whereas in OC chroma increased (ΔC = -3.3; P < .001). For both groups, a significant shift to more reddish tooth colors was observed. In almost all cases, color differences between baseline and follow-up exceeded the 50:50 acceptability thresholds for color differences (ΔE = 2.7) in both YC (≈90%) and OC (≈80%).
For both quinquagenarians and septuagenarians, clinically relevant changes in tooth color were observed after a decade; these could affect the long-term success of prosthetic restorations in terms of a satisfactory color match between natural teeth and dental prostheses. In contrast with the findings of cross-sectional studies, the changes were partially age-group-specific.
Tooth color can change over a decade. When fixed dental prostheses are planned, one should consider that changes of tooth color could lead to mismatch between a restoration and adjacent teeth during the period in clinical service.
评估两个年龄队列（年轻队列，YC：1950-1952 年；年长队列，OC：1930-1932 年）在平均 8 年的观察期内牙齿颜色的变化。
61 名参与者的 106 颗上颌中切牙接受了基线和随访检查（YC：n=46/OC：n=15）。使用分光光度计（VITA Easyshade 1）在两次测量时记录每个参与者的 1 或 2 颗未修复的测试牙的国际照明委员会颜色坐标。使用广义线性混合模型评估研究期间颜色坐标的变化，其中“参与者”变量作为随机效应。计算基线和随访之间的ΔE 和 E 颜色差异。
观察到颜色坐标的显著变化，OC 除外。变化的方向取决于队列。YC 的明度降低（ΔL=4.0；P<.001），而 OC 的色度增加（ΔC=-3.3；P<.001）。对于两个组，观察到牙齿颜色向更红的方向显著变化。在几乎所有情况下，基线和随访之间的颜色差异都超过了颜色差异的 50:50 可接受阈值（ΔE=2.7），在 YC（约 90%）和 OC（约 80%）中均如此。
对于 50 多岁和 70 多岁的人，在十年后观察到牙齿颜色的临床相关变化；这可能会影响修复体长期成功的颜色匹配，即在自然牙齿和牙科修复体之间。与横断面研究的结果相反，这些变化在一定程度上是年龄组特异性的。
牙齿颜色可能在十年内发生变化。当计划固定修复体时，应考虑到在临床服务期间，牙齿颜色的变化可能导致修复体与相邻牙齿之间的不匹配。
