Centre for Clinical, Oral and Translational Sciences, Faculty for Dental, Oral and Craniofacial Sciences, King's College London, Guy's Hospital, SE1 9RT, UK; Department of Prosthodontics, Faculty for Dental, Oral and Craniofacial Sciences, King's College London, Guy's Hospital, SE1 9RT, UK.
Centre for Clinical, Oral and Translational Sciences, Faculty for Dental, Oral and Craniofacial Sciences, King's College London, Guy's Hospital, SE1 9RT, UK.
J Dent. 2021 Sep;112:103738. doi: 10.1016/j.jdent.2021.103738. Epub 2021 Jun 25.
Our ability to detect dental wear on sequential scans is improving. This experiment aimed to determine if widely used surface registration methods were sufficiently accurate to distinguish differences between intervention groups on early wear lesions.
Baseline measurements were taken on human molar buccal enamel samples (n = 96) with a confocal scanning profilometer (Taicaan, UK). Samples were randomly assigned to subgroups of brushing (30 linear strokes 300 g force) before or after an acid challenge (10 min citric acid 0.3% immersion) for four test dentifrices (medium abrasivity NaF, medium abrasivity SnF, low abrasivity NaF and a water control). Post-experimental profilometry was repeated. 3D step height was analysed using WearCompare (www.leedsdigitaldentistry.co.uk/wearcompare, UK). Percentage Sa change was calculated using Boddies (Taicaan Technologies, Southampton, UK). Data were analysed in SPSS (IBM, USA).
The mean 3D step height (SD) observed when samples were brushed before the erosive challenge was -2.33 µm (3.46) and after was -3.5 µm (5.6). No significant differences were observed between timing of toothbrushing or dentifrice used. The mean % Sa change for the low abrasivity group (water control and low abrasivity NaF) was -10.7% (16.8%) and +28.0% (42.0%) for the medium abrasivity group (medium abrasivity NaF and SnF).
Detectable wear scars were observed at early stages of wear progression. However standard deviations were high and the experiment was underpowered to detect significant changes. Brushing with a low abrasivity dentifrice or water control produced a smoother surface whereas brushing with a high abrasivity dentifrice produced a rougher surface.
The methodology currently used to align sequential scans of teeth and measure change is too imprecise to measure early wear on natural enamel surfaces unless a large sample size is used. Further improvements are required before we can fully assess early wear processes on natural teeth using profilometry.
我们检测牙磨损的能力在逐步提高。本实验旨在确定广泛使用的表面配准方法是否足够精确，以区分不同干预组在早期磨损病变中的差异。
使用共焦扫描轮廓仪（英国 Taicaan）对人磨牙颊面釉质样本（n=96）进行基线测量。样本被随机分为刷牙前组（30 次 300g 力线性刷动）和刷牙后组（在酸性挑战后，10 分钟柠檬酸 0.3%浸泡），用于四种测试牙膏（中磨 SnF、中磨 NaF、低磨 NaF 和水对照）。实验后重复进行轮廓测量。使用 WearCompare（www.leedsdigitaldentistry.co.uk/wearcompare，英国）分析 3D 台阶高度。使用 Boddies（Taicaan Technologies，南安普顿，英国）计算 Sa 变化百分比。数据使用 SPSS（美国 IBM）进行分析。
在酸性挑战前刷牙时，样本观察到的平均 3D 台阶高度（SD）为-2.33µm（3.46），在酸性挑战后为-3.5µm（5.6）。未观察到刷牙时间或牙膏使用的差异。低磨组（水对照和低磨 NaF）的平均 Sa 变化百分比为-10.7%（16.8%），中磨组（中磨 NaF 和 SnF）为+28.0%（42.0%）。
在磨损进展的早期阶段观察到可检测的磨损痕迹。然而，标准差较高，实验没有足够的能力来检测显著的变化。使用低磨牙膏或水对照刷牙会使表面更光滑，而使用高磨牙膏刷牙会使表面更粗糙。
目前用于对齐牙齿的序列扫描和测量变化的方法不够精确，除非使用较大的样本量，否则无法测量天然牙釉质表面的早期磨损。在我们能够使用轮廓术充分评估天然牙齿的早期磨损过程之前，需要进一步改进。
