THE ACOUSTIC STETHOSCOPE USING ULTRASONIC PULSER DEVICE FOR THE PERIODONTAL TISSUES

利用超声装置进行生物组织功能监测和形态检测的声传感方法近年来在医学领域得到广泛应用。超声是非电离性的，相对安全，能够对患者的结构和功能状态进行无创、无损的监测。超声波探头发出的声波在生物组织中传播时，在声速不同的组织边界处产生回声。超声层析成像检测的是组织中不同于声介质层的回波。在这项研究中，我们设计了检测系统来获取人类牙周组织的声学特性，以检测其功能和结构状况。利用超声波对志愿者口腔组织进行声学研究。高频超声源（20MHz）应用于下颌牙槽部分上方的额部皮肤，或通过延迟线使用声探头应用于牙龈表面。与目标组织连接的探针延迟线将从活组织获得的回波传输到接收器，同时将声音传输到组织。声学探头上附着部分与皮肤的直径为2mm。传递到牙周组织的声束在不同组织层之间的边界上产生回声。在示波器上测量牙周组织的回波波形，重复加50次，取平均值。在额唇粘膜上的牙槽骨表面和具有健康牙周组织的牙龈表面产生强烈的尖刺。另一方面，在发炎的牙周牙龈上没有明显的尖刺。对牙周炎后牙槽骨突脱落后治愈恢复的牙龈组织同时获得一组小尖峰波。这些尖峰似乎表明无牙周病的健康软组织各层之间的边界点。我们可以从牙周组织表皮的回波波形中检测出健康牙周组织的特征信号，而不需要昂贵的超声设备进行二维检测。少

Acoustic sensing methods using ultrasound devices for the functional monitoring and morphological inspection of biological tissues are recently receiving widespread through medical field. Ultrasound being non-ionizing nature, are relatively safe have capabilities for the non-invasive and non-destructive monitoring of the structural and functional states of patients. In the biological tissues in which the acoustic wave sent from ultrasonic probe is propagated, the echo is generated in the boundary in the organization in which the sound velocity differs. The ultrasonic tomography detects the echo got from the layer which differs as acoustic medium in the tissues.In this study, we designed the detection system to obtain acoustic properties from human periodontal tissues for inspecting functional and structural conditions. The acoustic investigation by the ultrasonic wave for oral tissue was carried out for the volunteer. High frequency, ultrasound source (20MHz) was applied to the mandibl … More e frontal skin over the alveolar portion, or to the surface of gingival using the acoustic probe via delay line. The delay line of the probe with the connection to the target tissue transmitted the echo which was obtained from the live tissue to the receiver, while the sound was transmitted to the tissue. The diameter of the attached portion to the skin on the acoustic probe was 2mm. The transmitted sound beam to the periodontal tissue generated the echoes on the boundary between the layers of different tissues. The echo waveforms from the periodontal tissues were measured on the oscilloscope and was added 50 times repeatedly, then averaged. An intensive sharp spike which was generated at the surface of alveolar bone obtained on the frontal labial mucosa, and on the gingival surface having healthy periodontal tissue. On the other hand, no intensive spike was not obtained from the inflamed periodontal gingival. A group of the small spike wave were obtained simultaneously on the gingival tissues which had lose the processes of alveolar bone then have been cured and recovered from periodontitis. These spikes were seemed to indicate the boundary points between the layers in the healthy soft tissue free from periodontal desease. We could detected the distinguished signal signed the healthy periodontal tissue from the echo waveforms from epidermis of periodontal tissues without a two-dimensional inspection system which was required very expensive ultrasound equipments. Less