Bests & Worsts Reviews from Amazon

My Oral-B Professional toothbrush was growing weak after four years of use, so I began searching for a replacement. Dr. Tung's Ionic Toothbrush looked intriguing and promotional material claimed to back up its efficacy with clinical studies, so I ordered one. The Japanese-made toothbrush is approximately the size and weight of a normal, high quality manual toothbrush. The styling recalls American made clinical instruments of the sixties. The bristle arrangement is unusual, with interspersed long, soft nylon strands standing over shorter, sturdier bristles. The brush head can be replaced. The toothbrush comes with one spare brush head and one already mounted on the toothbrush. The Ionic Toothbrush has a 3V battery embedded in the handle. The battery is not replaceable but is supposed to last several years. The battery level can be checked by depressing a button on the handle which will light up a red LED if the battery is still charged. The handle is wrapped with a metal band that is connected to the positive pole of the battery. The toothbrush head is not charged. Rather, a small hole exists in the stem close to the brush head. This hole exposes the metal mounting rod for the brush head. The rod is connected to the negative pole of the 3V battery. There is a resistance of approximately 1 million ohms between my wet hand and my mouth. A 3-volt potential difference across this load will result in a current of only 3 microamps for a power consumption rate of a mere 9 microwatts. However, this assumes direct contact from my mouth with the negatively charged metal rod, which never occurs. Instead, electricity has to flow through saliva for a distance of several millimeters to reach mouth tissue. This imposes a resistance of several more million ohms, bringing the total brushing current down to well under one microamp and the electric power to under one microwatt. In comparison, there are about three microwatts of power impinging upon every square meter of the Earth's surface from cosmic microwave background radiation left over from the Big Bang. A quartz wristwatch consumes about one microwatt of power. A typical wireless router signal carries over 70,000 times more power. An ordinary LED pocket flashlight uses several million times more electrical power than Dr. Tung's Ionic Toothbrush delivers for cleaning. Given the exceedingly low voltage (electrostatic voltages that cause paper to cling to a balloon are on the order of thousands of volts) and the minuscule electric power delivery, it is difficult to see any potential for efficacy. Indeed, if you study some of the research backing the Ionic Toothbrush, you will find issues. For instance, one study reported no benefit from using the Ionic Toothbrush for users who already had good oral hygiene. Despite my growing skepticism, I brushed my teeth with Dr. Tung's Ionic Toothbrush for a period of ten days. Almost immediately I could detect that my teeth were not being cleaned nearly as well as with electric toothbrushes (including brushes from Interplak, Oral-B, Waterpik and Sonicare). After a week using Dr. Tung's Ionic Toothbrush, by simply running my tongue against my teeth I could easily feel significant amounts of plaque that had accumulated on them in that short time. Consequently, I ordered from Amazon the Oral-B Smartseries 5000 Professional Care Rechargeable Electric Toothbrush. With rebate, this outstanding toothbrush only cost me about $50 and delivers far better cleaning for my teeth than did Dr. Tung's Ionic Toothbrush. In summary, I detected no better performance from Dr. Tung's Ionic Toothbrush than what one would expect from a normal, manual toothbrush costing far less. Moreover, while the principle of electrostatic manipulation of plaque might indeed lead to better cleaning, the science behind its implementation in the Ionic Toothbrush is specious. For me, Dr. Tung's Ionic Toothbrush failed to clean my teeth nearly as well as good electric toothbrushes from Interplak, Oral-B, Waterpik or Sonicare.