University of Alberta, Department of Dentistry, Faculty of Medicine and Dentistry, Room 4051, Dentistry/Pharmacy Centre, Edmonton, AB Canada T6G 2N8.
Arch Oral Biol. 2012 Jun;57(6):760-8. doi: 10.1016/j.archoralbio.2011.11.010. Epub 2011 Dec 3.
Investigate the effect of therapeutic Low Intensity Pulsed Ultrasound (LIPUS) on human dentine-pulp complex in an in vitro model.
92 premolars were extracted from 23 adolescent orthodontic patients. The premolars were sectioned transversely into 600 μm thick slices. The slices were divided into two main groups according to how often the LIPUS was applied (single or daily application), and then subdivided into five subgroups each (5, 10, 15 and 20 min and one control group). The tooth slices were cultured at (37 °C/5% CO(2)) in a humidified incubator where medium was changed every 48 h. LIPUS was applied using a 3.9 cm(2) transducer that produces an incident intensity of 30 mW/cm(2). After five days, tissue was harvested for histomorphometrical analysis and real time PCR to investigate expression of genes of interest (Collagen I, DMP1, DSPP, TGF-β1, RANKL and OPG).
Histomorphometric analyses revealed that odontoblast cell count was higher in the single application groups (5, 10 and 15 min, respectively) than in the control and other treatment groups. Predentin thickness was higher in the single application group (10, 5 and 15 min) respectively than in the daily application group and the control groups, however they were not significantly different from each other. Real time PCR demonstrated no statistically significant difference between the groups in the expression of Collagen I, DMP1, TGF-β1, DSPP, RANKL and OPG.
Reproducible responses from cultured dentine-pulp complex were observed in groups with single application of LIPUS for 5, 10 and 15 min.
在体外模型中研究治疗性低强度脉冲超声（LIPUS）对人牙本质-牙髓复合体的影响。
从 23 名青少年正畸患者中提取 92 颗前磨牙。前磨牙被横向切成 600μm 厚的切片。根据 LIPUS 应用的频率（单次或每日应用）将切片分为两组，然后每个组再分为五个亚组（5、10、15 和 20 分钟以及一个对照组）。将牙切片在（37°C/5%CO2）的加湿培养箱中培养，其中培养基每 48 小时更换一次。使用产生 30mW/cm2 入射强度的 3.9cm2 换能器施加 LIPUS。五天后，收获组织进行组织形态计量学分析和实时 PCR，以研究感兴趣基因（I 型胶原、DMP1、DSPP、TGF-β1、RANKL 和 OPG）的表达。
组织形态计量学分析显示，与对照组和其他治疗组相比，单次应用组（分别为 5、10 和 15 分钟）的成牙本质细胞计数更高。牙本质前体细胞厚度在单次应用组（分别为 10、5 和 15 分钟）更高，与每日应用组和对照组相比，但彼此之间无显著差异。实时 PCR 显示，各组在 I 型胶原、DMP1、TGF-β1、DSPP、RANKL 和 OPG 的表达上无统计学差异。
在单次应用 LIPUS 5、10 和 15 分钟的组中观察到培养牙本质-牙髓复合体具有可重复的反应。
