School of Dental Technology, Taipei Medical University, Taipei, 11031, Taiwan.
Department of Oral Biomaterials Development Engineering, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, Tokyo, 113-8549, Japan.
Clin Oral Investig. 2022 Mar;26(3):3041-3048. doi: 10.1007/s00784-021-04287-8. Epub 2021 Nov 30.
The effect of toothbrushing on the color, relative translucency, and surface roughness of extrinsically stained zirconia dental restorations is still unclear. The purpose of the present study was to evaluate the optical properties and surface textures of extrinsically stained or glazed partially stabilized zirconia with 5 mol% yttria (5Y-PSZ) after toothbrushing by determining changes in the color, translucency parameter (TP), and surface roughness.
Specimens (2 mm thick; n = 50) were sectioned from 5Y-PSZ blanks. Three brands of powdered stains (namely VI, SH, IV) and a glaze (GL) were used to extrinsically stain the specimen surfaces (n = 10 per group). The specimens were subjected to 10,000-50,000 simulated toothbrushing strokes using a toothpaste slurry (Ora2 PREMIUM Stain clear paste). The color parameters were measured before staining or glazing and before and after simulated brushing. The color changes and TP values can be calculated before and after simulated brushing. The surface roughness was also evaluated.
Significant changes were found in the shade and TP values of 5Y-PSZ after extrinsic staining, but no significant changes were found after toothbrushing, irrespective of the staining brand (p > 0.05). The surface roughness of the characterized 5Y-PSZ specimens decreased after toothbrushing, whereas that of the non-characterized 5Y-PSZ group increased.
Toothbrushing markedly affects the surface roughness of extrinsically stained or glazed 5Y-PSZ specimens, whereas no impacts on the color or translucency were observed.
For esthetic reasons, clinicians and dental technicians prefer to apply extrinsic stains to zirconia restorations, which profoundly affects its appearance. The limited influence of toothbrushing on color and translucency of 5Y-PSZ is promising for clinical applications.
关于刷牙对着色的氧化锆牙科修复体的颜色、相对半透明度和表面粗糙度的影响仍不清楚。本研究的目的是通过测量颜色、半透明度参数（TP）和表面粗糙度的变化，评估经牙刷刷洗后，用 5 摩尔%氧化钇（5Y-PSZ）处理的外染色或上釉的部分稳定氧化锆的光学特性和表面纹理。
从 5Y-PSZ 坯料中切割出（2mm 厚；n=50）试件。使用三种品牌的粉末污渍（即 VI、SH、IV）和一种釉料（GL）对外染色试件表面（每组 n=10）。使用牙膏糊剂（Ora2 PREMIUM Stain clear paste）对试件进行 10000-50000 次模拟刷牙。在染色或上釉之前以及模拟刷牙之前和之后测量颜色参数。可以计算模拟刷牙前后的颜色变化和 TP 值。还评估了表面粗糙度。
5Y-PSZ 经外染色后，颜色和 TP 值发生显著变化，但刷牙后，无论染色品牌如何，均无显著变化（p＞0.05）。经牙刷刷洗后，特征化 5Y-PSZ 试件的表面粗糙度降低，而非特征化 5Y-PSZ 组的表面粗糙度增加。
刷牙显著影响外染色或上釉的 5Y-PSZ 试件的表面粗糙度，而对颜色或半透明度无影响。
出于美观原因，临床医生和牙科技术人员更喜欢在氧化锆修复体上应用外染色剂，这会极大地影响其外观。刷牙对 5Y-PSZ 颜色和半透明度的有限影响对临床应用有一定的前景。
