Study of the measurement of halitosis by thin film semi-conductor sensor

目前，在普通口腔门诊中，对主诉口臭的患者，主要依靠口腔医生的嗅觉来判断是否有口臭。但受试者的嗅觉会因身体状况或年龄而改变。为了避免这些麻烦，必须通过标准方法测试受试者的嗅觉，并且需要多个受试者。本文报道了用气相色谱法测定挥发性硫化物（VSC）浓度与口臭的判断方法相一致的结果。但在一般口腔临床中，由于需要特殊的技术和高昂的成本，制备气相色谱仪非常困难。本课题旨在研制一种对挥发性有机化合物具有高选择性的氧化锌薄膜半导体嗅觉传感器。我们制作了第一、第二次试用嗅觉仪，并测试了它们的灵敏度。 ...更多信息 效率。结果如下。该传感器的灵敏度足以检测VSC的明显口臭。对口腔空气中典型有机物丙酮和乙醇的灵敏度比VSC低1/10，表明该传感器具有良好的选择性。对标准口臭空气进行重复测量试验，具有足够的重现性，采用酸性吸附过滤器提高了选择性。口腔空气室可储存一定量的口腔空气，有利于减小检测误差，防止唾液污染检测通道，并对口腔进行了实际测量，预热时间约为3 min，测量时间约为1.5 min，下一次测量时间约为3 min。但对同一人随通过时间的重复测量显示出相当大的差异。这种差异是由口腔气味随时间的变化引起的，还是由口腔空气采样方法引起的，有待进一步研究。少

The present time, in general dental clinic, the judgment of halitosis of the patients who complaining bad breath is due to the olfactory sense of dentists. But the olfactory sense of panelists is changed by their physical condition or aging. For avoiding these troubles, the panelists must be tested of their olfactory sense by standard method and plural panelists are needed. Because of these many limitations, reliable analytical method was expected.We reported that the concentration of volatile sulfur compounds(VSC) analyzed by gas chromatography is well correspond to the judgement of halitosis by panel. But in general dental clinic, it is very hard to prepare the gas chromatography, for needed special techniques and high cost. So, the development of convenient olfactometer was expected.We aimed to develop a convenient olfactometer composed of thin film zinc oxide semi-conductor sensor which is high selective to VSC. We made the first and the second trial olfactometer and tested their e … More fficiency. The result are as follows. The sensitivity of this sensor is sufficient to detect noticeable halitosis revel of VSC. The sensitivity revel of acetone and ethylalcohol, the typical organic contents in mouth air, are 1/10 fold lower than VSC which shows good selectivity of this sensor. Repeating measuring test to standard halitosis air is sufficient reproducibility.The selectivity is improved by using acidic absorbent filter. A mouth air chamber which accumulate a certain volume of mouth air, is useful to decreasing the detective variance and is also useful to protect the contamination of saliva into the detective path.The practice measuring was done to mouths, using this olfactometer, and the time for preheat is about 3 minutes, measuring time is one and half minutes and about 3 minutes is necessary for the next measuring. But repeating measurements to same person with passage time showed considerable variance. Further study is necessary whether this variance was caused by the changes of mouth odor with passage of time or whether by the sampling methods of mouth air. Less