Unfortunately, along with the whiteness came sensitivity issues. These lasers emitted high amounts of heat--over 52 degrees centigrade, which is 122 degrees farenheit-yeow! This heat too often caused irreversible changes in teeth, making them permanently sensitive and even occasionally requiring root canals. Despite incremental improvements here and there, the heat continued to cause problems and pain. Even as recent as the late Nineties, newer versions came out that activated the oxygen better (such as the Argon C02 lasers), but the heat-and the problems associated with it--remained.
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