Prosthodontic Department, King's College London Dental Institute at Guy's, King's College and St Thomas' Hospitals, UK.
Prosthodontic Department, King's College London Dental Institute at Guy's, King's College and St Thomas' Hospitals, UK.
J Dent. 2018 Mar;70:124-128. doi: 10.1016/j.jdent.2018.01.005. Epub 2018 Jan 12.
To investigate the differences in susceptibility of the surface of native and polished enamel to dietary erosion using an in-situ model.
Thirty healthy volunteers (n = 10 per group) wore mandibular appliances containing 2 native and 2 polished enamel samples for 30 min after which, the samples were exposed to either an ex-vivo or in-vivo immersion in orange juice for 5, 10 or 15 min and the cycle repeated twice with an hour's interval between them. Samples were scanned with a non-contacting laser profilometer and surface roughness was extracted from the data, together with step height and microhardness change on the polished enamel samples.
All volunteers completed the study. For native enamel there were no statistical difference between baseline roughness values versus post erosion. Polished enamel significantly increased mean (SD) Sa roughness from baseline for each group resulting in roughness change of 0.04 (0.03), 0.06 (0.04), 0.04 (0.03), 0.06 (0.03), 0.08 (0.05) and 0.09 (0.05) μm respectively. With statistical differences between roughness change 45 min in-vivo versus 45 min ex-vivo (p < 0.05). Microhardness significantly decreased for each polished group, with statistical differences in hardness change between 30 min in-vivo versus 30 min ex-vivo (p < 0.05), 45 min in-vivo versus 30 min ex-vivo (p < 0.01), 45 min in-vivo versus 45 min ex-vivo (p < 0.01).
The native resistance to erosion provided clinically is a combination of the ultrastructure of outer enamel, protection from the salivary pellicle and the overall effects of the oral environment. CLINICALTRIALS.
NCT03178968.
This study demonstrates that outer enamel is innately more resistant to erosion which is clinically relevant as once there has been structural breakdown at this level the effects of erosive wear will be accelerated.
使用原位模型研究天然釉质和抛光釉质表面对饮食侵蚀敏感性的差异。
30 名健康志愿者（每组 10 名）佩戴下颌矫治器，其中含有 2 个天然釉质样本和 2 个抛光釉质样本，30 分钟后，样本分别在体外或体内暴露于橙汁中 5、10 或 15 分钟，两次之间间隔 1 小时。用非接触式激光轮廓仪扫描样本，从数据中提取表面粗糙度，并提取抛光釉质样本的台阶高度和显微硬度变化。
所有志愿者均完成了研究。对于天然釉质，在侵蚀后与基线粗糙度值相比，没有统计学差异。对于抛光釉质，每个组的 Sa 粗糙度均显著高于基线值，粗糙度变化分别为 0.04（0.03）、0.06（0.04）、0.04（0.03）、0.06（0.03）、0.08（0.05）和 0.09（0.05）μm。45 分钟体内与 45 分钟体外的粗糙度变化之间存在统计学差异（p<0.05）。每个抛光组的显微硬度均显著降低，体内 30 分钟与体外 30 分钟之间的硬度变化存在统计学差异（p<0.05）、体内 45 分钟与体外 30 分钟之间的硬度变化（p<0.01）、体内 45 分钟与体外 45 分钟之间的硬度变化（p<0.01）。
天然釉质的抗侵蚀能力是由外釉质的超微结构、唾液膜的保护和口腔环境的综合作用提供的。
临床试验。
NCT03178968。
本研究表明，外釉质先天更能抵抗侵蚀，这在临床上是相关的，因为一旦达到这个水平的结构破坏，侵蚀性磨损的影响将加速。
