Meister Jörg, Franzen René, Forner Katharina, Grebe Henning, Stanzel Sven, Lampert Friedrich, Apel Christian
RWTH Aachen University, Department of Conservative Dentistry, Periodontology, and Preventive Dentistry, Germany.
J Biomed Opt. 2006 May-Jun;11(3):34030. doi: 10.1117/1.2204028.
The theory of the ablation of dental hard tissue with erbium lasers is based on a process of thermomechanical interaction, which is explained by the absorption of the radiation in the water component of the tissue. The abrupt evaporation of the water is the cause of tissue fragments being blasted out of the tooth structure. The aim of this study is to examine the effect of the water contained in dental hard tissues on the efficiency of ablation. 192 specimens of both bovine dental enamel and bovine dentin are irradiated with an Er:YAG and an Er,Cr:YSGG laser. Half of the specimens are dehydrated beforehand. Irradiation is carried out in subgroups: without water spray and with water spray at flow rates of 0.8 and 3 mls. The ablated volume is determined following histological preparation. Only in dentin, and then only with irradiation with the Er:YAG laser, is the water contained in the tissue found to have a significant influence (p < 0.0001) on the ablated volume. The water content has no effect on the efficiency of laser ablation in any of the other test groups. In contrast, the externally supplied water always has a significant influence on the effectiveness of the ablation process.
铒激光消融牙体硬组织的理论基于热机械相互作用过程,这一过程可通过组织中水成分对辐射的吸收来解释。水的突然蒸发是组织碎片从牙齿结构中被喷射出来的原因。本研究的目的是研究牙体硬组织中所含水分对消融效率的影响。用铒钇铝石榴石激光(Er:YAG)和铒铬钇钪镓石榴石激光(Er,Cr:YSGG)对192个牛牙釉质和牛牙本质标本进行照射。一半标本预先脱水。照射在亚组中进行:不喷水以及以0.8毫升/秒和3毫升/秒的流速喷水。在组织学制备后测定消融体积。仅在牙本质中,且仅在用Er:YAG激光照射时,发现组织中所含水分对消融体积有显著影响(p < 0.0001)。在任何其他测试组中,含水量对激光消融效率均无影响。相比之下,外部供应的水总是对消融过程的有效性有显著影响。