Temperature examination in the rectum is the traditional gold standard measurement used to estimate core temperature (oral temperature is affected by hot or cold drinks and mouth-breathing). Rectal temperature is expected to be approximately one Fahrenheit degree higher than an oral temperature taken on the same person at the same time. Ear thermometers measure eardrum temperature using infrared sensors. The blood supply to the tympanic membrane is shared with the brain . However, this method of measuring body temperature is not as accurate as rectal measurement and has a low sensitivity for fevers, missing three or four out of every ten fevers in children.  Ear temperature measurement may be acceptable for observing trends in body temperature but is less useful in consistently identifying fevers.
Q: Can oral lichen planus lead to oral cancer?
A: This association remains controversial, but there are reported cases of this occurring. This concern reinforces the essential need to obtain an accurate diagnosis, typically with a biopsy. All patients with oral lichen planus should have a periodic evaluation to asses the efficacy of therapy and to monitor for suspicious changes. If your oral lichen planus does not respond to treatment or if you should notice a significant change, you should contact your heath care provider for further evaluation.