There are two categories of mouthwash: cosmetic rinses and therapeutic rinses. Cosmetic mouthwash helps to control bad breath (which can improve confidence) and leaves a pleasant aftertaste. It won’t kill odor causing bacteria (think pus) or inactivate the compounds that are also responsible for bad smells (think rotten eggs). They have just a masking function.
Therapeutic rinses work to get to the root cause of the bad breath. Some reduce the amount of plaque (bacteria) responsible for gingivitis. Others neutralize the acids produced by bacteria lessening the chance of cavities. Other mouthwashes target xerostomia (dry mouth).
Fluoride and xylitol as ingredients have been found to be very helpful in cavity prevention and should be used daily for those susceptible to decay. These are usually over the counter. Prescription mouthwashes are used for specific problems and require a dentist’s diagnosis and oversight.
Mouthwashes, either cosmetic or therapeutic, do not fix specific odor causing problems like deep cavities, untreated gum disease or mouth infections. They only mask or prevent. It is important to have a dentist figure out where that funky smell is coming from. We can usually find the source quickly. Please do your loved ones a favor and get it checked out.