Final answer:
Anosmia, or loss of sense of smell, is typically a bilateral condition and can result from blunt trauma, aging, or other factors, with the potential for temporary or permanent effects depending on the severity of the nerve damage.
Step-by-step explanation:
Loss of the sense of smell, known as anosmia, is usually a bilateral condition. Anosmia can occur from blunt trauma to the head or with aging, impacting the functionality of the olfactory system. When testing for the sense of smell, common smells such as coffee or mint are presented to one nostril at a time to assess olfactory function. In cases of severe blunt force trauma, such as in a motor vehicle accident, all the olfactory nerve fibers may be sheared and unable to regenerate, leading to permanent anosmia. However, if the olfactory nerve is not completely severed, the loss of smell might be temporary, with the potential for olfactory neurons to eventually reconnect. Factors such as repeated head trauma, certain pharmaceuticals, respiratory infections, or allergies may also result in temporary or permanent anosmia.