THE ACOUSTIC STETHOSCOPE USING ULTRASONIC PULSER DEVICE FOR THE PERIODONTAL TISSUES

利用超声设备对生物组织进行功能监测和形态检测的声学传感方法近年来在医学领域得到了广泛的应用。超声具有非电离性质，相对安全，能够对患者的结构和功能状态进行非侵入性和非破坏性的监测。在传播超声探头发出的声波的生物组织中，回波是在组织中声速不同的边界上产生的。超声层析成像是对组织中不同声媒层的回声进行检测，本研究设计了一套检测系统，以获取人体牙周组织的声学特性，用于检测牙周组织的功能和结构状况。对受试者进行了口腔组织超声波声学检查。将高频超声源(20 MHz)应用于下颌骨…更多的额部皮肤覆盖在牙槽部分，或通过延迟线使用声学探头到达牙龈表面。与目标组织连接的探头的延迟线将从活体组织获得的回波传输到接收器，而声音被传输到组织。声学探头皮肤附着部直径为2 mm。传输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声波形，重复相加50次，取平均值。在牙槽骨表面形成的一种强烈的尖刺，产生于前唇粘膜和牙周组织健康的牙周表面。另一方面，炎症牙周炎的牙周组织中未见明显的尖刺。牙周炎愈合后，在牙槽骨突起消失的牙周组织上同时出现一组小棘波。这些尖峰似乎表明了健康软组织中没有牙周病的各层之间的分界点。从牙周组织表皮的回波波形中可以检测出代表健康牙周组织的识别信号，而不需要二维检测系统，这需要非常昂贵的超声设备。较少

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