Cariology and Operative Dentistry, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45, Yushima, Bunkyo-ku, Tokyo 113-8549, Japan.
Dent Mater. 2011 Sep;27(9):915-25. doi: 10.1016/j.dental.2011.05.003. Epub 2011 Jun 12.
Regardless of the cause, gap formation at the tooth-restoration interface may result in treatment failure; non-destructive assessment and monitoring of these defects are important. The aim of this in vitro study is to assess the tooth-restoration interface using a non-invasive technique; swept source optical coherence tomography (SS-OCT) and to confirm the findings with confocal laser scanning microscope (CLSM).
Cylindrical class-I cavities (3mm in diameter and 1.5mm in depth) were prepared in the occlusal surface of human premolars. Each cavity was restored using an all-in-one adhesive system (Clearfil Tri-S Bond) and one of the three types of composites placed in bulk; Majesty Posterior, AP-X and Majesty LV (all by Kuraray Medical, Japan). Ten serial cross-sectional images of the whole restored cavity were obtained by SS-OCT at 1319 nm center wave length, to which locations the specimens were later trimmed, polished and observed under CLSM. An image analysis software was used to detect significant peaks in the signal intensity at the resin-dentin interface of the cavity floor. The presence and dimensions of gaps at the interface were also confirmed by CLSM.
Increased SS-OCT signal intensity along the interface corresponded well to the interfacial gaps detected by CLSM. The actual gap size detected ranged from 26 μm to 1.9 mm in length, and the universal composite APX showed lowest interfacial gaps.
SS-OCT imaging technology can be used to non-invasively detect and quantify micrometer gaps at the bottom of composite restorations, and potentially become a monitoring tool for composite restorations both in the laboratory research, and in the clinics.
无论病因如何，牙体修复界面的间隙形成都可能导致治疗失败；因此，对这些缺陷进行非破坏性评估和监测非常重要。本体外研究的目的是使用非侵入性技术评估牙体修复界面，即扫频源光学相干断层扫描（SS-OCT），并用共聚焦激光扫描显微镜（CLSM）确认检测结果。
在人前磨牙的咬合面制备直径为 3mm、深度为 1.5mm 的Ⅰ类圆柱形窝洞。使用全酸蚀粘接系统（Clearfil Tri-S Bond）和 3 种块状复合材料中的 1 种对每个窝洞进行修复： Majesty Posterior、AP-X 和 Majesty LV（均由日本 Kuraray Medical 公司提供）。在 1319nm 中心波长下，使用 SS-OCT 获得整个修复窝洞的 10 个全剖面图像，然后将标本切割、抛光，并在 CLSM 下观察。使用图像分析软件检测腔底树脂-牙本质界面处信号强度的显著峰值。通过 CLSM 还可以确认界面处间隙的存在和尺寸。
沿界面的 SS-OCT 信号强度增加与 CLSM 检测到的界面间隙吻合良好。实际检测到的间隙尺寸范围从 26μm 到 1.9mm，通用型复合树脂 APX 显示出的界面间隙最小。
SS-OCT 成像技术可用于非侵入性地检测和量化复合修复体底部的微米级间隙，并有可能成为实验室研究和临床中复合修复体的监测工具。
