A Study on Electro-Magnetic Interferences for ICD cause of Dental Electric Equipments

ICD（植入式心律转复除颤器）用于在心律失常的情况下人工刺激心脏。随着老年人口的增加，ICD患者的数量也在增加。ICD会受到电气设备的影响，即电磁干扰（EMI），在牙科治疗中，需要使用电气牙科设备，但这些设备对ICD的影响尚不清楚，报道也不多。最近的ICD因此只有在必要时才能发挥作用。我们评估了最近的电动牙科设备旨在系统化的安全性和积极的牙科治疗。材料和方法我们测试了12种类型24设备的电动牙科设备正在鹤见大学牙科学院医院使用。初步检验：采用磁通门磁强计测量磁通密度。模拟模型：在一个与人体大小相同的水槽中，注入生理盐水，在水槽中注入生理盐水。结果：少数牙科电子设备的EMI抑制ICD，根据EMI的原因分为两类：第一类是电子设备的电源部分抑制起搏距离为27 cm，第二类是电子设备的电源部分抑制起搏距离为27 cm。该值足以影响牙科治疗的实际状态。在第2类情况下，某些电根测量设备仅在通电/断电定时使用时才抑制起搏。所有数据均由编程器打印出来，存储和分析。我们建议在使用电牙科设备时必须采取预防措施。本检查是在有限的条件下进行的。我们的设置是在最恶劣的条件下进行的，我们必须认识到ICD和牙科电子设备的特点，所以牙科治疗本身没有局限性。

ICD(implantable cardioverter-defibrillator) are used to artificially stimulate the heart in case of arrhythmia. As the population of elderly increases, number of patients with ICD increase. ICD can be affected by electrical equipment, known as electromagnetic interference (EMI).In dental treatment, it is necessary to use electrical dental equipments, but influences of these devices to ICD are unknown and reported only a few. Recent ICD therefore only functions when necessary.We evaluated recent electrical dental equipment aimed to systematize safety and positive dental treatment.Material and methodsWe tested 12 type 24 devices of electrical dental equipments that are being used in Tsurumi Univ. School of Dental Medicine hospital..Preliminary examination : Used flux-gate magneto-meter to measurement of flux density. If the value of flux density was high, these equipments were tested in simulation model.Simulation model : A water tank designed as the same size of the human body was filled with physiological salt solution. ICD was placed under the solution 12mm, connected by telemetric system to programmer.Results : ICD were inhibited by EMI of few electrical dental devices.These device were classified into two categories, according to cause of EMI.In case of type 1, some devices power supply unit of electrical device inhibit to pacing distance of 27 cm. This value was enough to influence to actual state of dental treatment.In case of type 2, some electrical root measurement device inhibit to pacing only when power on/off timing usage.All data was printed out by programmer, stored and analyzed.We suggest that precaution must be taken with the usage of electrical dental devices.This examination was done in limited conditions. Our settings were placed on most severe conditions.We must recognize the characteristics of ICD and electrical dental devices, so there are no limitation of dental treatment itself.