Meire Maarten, Mavridou Athina, Dewilde Nikolaas, Hommez Geert, De Moor Roeland Jozef Gentil
Department of Operative Dentistry and Endodontology, Ghent Dental Laser Center, Dental School, Ghent University, Gent, Belgium.
Photomed Laser Surg. 2009 Aug;27(4):611-6. doi: 10.1089/pho.2008.2302.
This study investigates the effects of Nd:YAG laser irradiation on apical and coronal seals, when used prior to two root canal filling techniques.
Limited information exists regarding the effects of morphologic changes to dentin walls following Nd:YAG laser irradiation on the sealing ability of root fillings.
Two hundred forty teeth were analyzed by observing coronal and apical leakage of Indian ink (DL), and 60 were analyzed for through-and-through leakage using the fluid transport model (FTM). The Nd:YAG laser parameters were 1.5 W, 100 mJ, and 15 Hz (four times for 5 s at 20 s intervals). Each group consisted of a lased and a nonlased subgroup: each subgroup had root fills done by either cold lateral condensation (CLC) or hybrid condensation (HC). Leakage was assessed after 48 h, and then at 1, 6, and 12 months. The DL group was divided into four groups of 15 teeth for each evaluation point. Through-and-through leakage (L in microliters/day) was measured for 48 h under a pressure of 1.2 atm using FTM, and recorded as L = 0 (L1), 0 < L <or= 10 (L2), or L > 10 (L3).
Apical and coronal dye leakage was observed in all groups. Significant differences (p < 0.05) in apical leakage were found between HC and HC + Nd after 1, 6, and 12 months, and between CLC and CLC + Nd at 6 and 12 months. No significant differences were found between laser-irradiated and non-laser-irradiated groups with FTM.
Pulsed Nd:YAG laser irradiation following root canal preparation may reduce apical leakage in association with hybrid gutta-percha condensation.
本研究调查钕钇铝石榴石（Nd:YAG）激光照射在两种根管充填技术之前使用时，对根尖封闭和冠部封闭的影响。
关于Nd:YAG激光照射后牙本质壁形态学变化对根管充填封闭能力的影响，现有信息有限。
通过观察印度墨水（DL）的冠部和根尖渗漏情况，对240颗牙齿进行分析，使用液体传输模型（FTM）对60颗牙齿进行全牙贯通性渗漏分析。Nd:YAG激光参数为1.5W、100mJ和15Hz（每隔20秒进行4次，每次5秒）。每组包括一个激光照射亚组和一个未照射亚组：每个亚组的根管充填分别采用冷侧向加压充填（CLC）或混合加压充填（HC）。在48小时后，然后在1、6和12个月时评估渗漏情况。DL组在每个评估点分为四组，每组15颗牙齿。使用FTM在1.2个大气压的压力下测量48小时的全牙贯通性渗漏（以微升/天为单位的L），并记录为L = 0（L1）、0 < L ≤ 10（L2）或L > 10（L3）。
所有组均观察到根尖和冠部染料渗漏。在1、6和12个月时，HC组和HC + Nd组之间以及在6和12个月时CLC组和CLC + Nd组之间，根尖渗漏存在显著差异（p < 0.05）。FTM测量中，激光照射组和未照射组之间未发现显著差异。
根管预备后进行脉冲Nd:YAG激光照射，与混合牙胶加压充填联合使用时，可能会减少根尖渗漏。
