Bad Breath After Dental Work, Good and Bad Mouth Bacteria

IsabelleU69 Asked :

Ask a Doctor Online Now!

I recently had a dental bridge inserted to replace a badly decayed tooth that had to be removed. The dentist had also prescribed me antibiotics because he believed an abscess was developing on the other side. After that I noticed that my breath has been quite foul and even my partner has detected the bad odor. I tried many mouth washes and gum and so on but nothing seems to have helped. I have read about probiotics for bad breath and the effect of bad bacteria in the mouth and tried this as well but no relief.

I am wondering if that round of antibiotics killed off all the good bacteria in my mouth and now the bad bacteria have set in. I have no other mouth or teeth problems and even my gums are quite healthy. I am a light smoker but my bad breath problem at the moment is not that stale tobacco smell. In the mornings, it’s very offensive like something is decaying similar to a garbage can. During the day it is sometimes a mixture of fishy, stale and a very mild version of the morning breath.


This question was posted under the Bad Morning Breath Causes article.

Any response by the Health Hype team does not constitute a medical consultation and the advice should be viewed purely as a guide. Always consult with your doctor before making any changes to your current treatment program. The information provided in this article is not an authoritative resource on the subject matter and solely intends to guide the reader based on the questions asked and information provided.


Dr. Chris Answered :

There are a number of causes of persistent bad breath (halitosis) that should first be excluded before searching further for other causes. The two most important issues here is dental hygiene and a dry mouth. You have mentioned previous tooth decay and it is important to reassess your dental care regimen. Brushing twice a day, flossing and using a mouth rinse all play a part in dental hygiene. First ensure that you are meeting with these basic steps to reduce the breakdown of food stuck between your teeth by bacteria. It is the main cause of bad breath and do not forget to brush your tongue as well because the papillae on the tongue also traps specks of food which are consumed by bacteria.

The next issue here is mouth dryness. Smokers and mouth breathers commonly experience dryness of the mouth and other conditions that affect the salivary glands could also contribute to this. Reduced saliva content changes the pH of the mouth which further contributes toward decay. It’s more about the amount of saliva in your mouth rather than just drinking water. Certain sugar free gum can help with increasing salivation but be weary of artificially sweetened gum as these types of sweeteners can also serve as a food source for bacteria in the mouth. Remember that saliva production decreases while you are asleep so you lose some of the natural antibacterial properties of saliva during this time, hence the bad morning breath.

The cavities within the human body – mouth, gastrointestinal tract and vagina – maintain a microenvironment for the natural flora (“good bacteria”) to grow and thrive. Good bacteria means that these bacteria can exist in these areas without causing disease but will still consume nutrients and result in a bad odor. The mouth, however, is different from the other cavities in that it is constantly exposed to all types of microorganisms from the air, in the food we eat and fluids we drink. Even kissing can transfer bacteria from the mouth of one person to another.

Bad bacteria is entering the mouth all the time and the mouth cavity has many in-built mechanisms to maintain its environment and limit the growth of any bacteria (good or bad). They may still exist in small populations within the mouth. Unless you are experiencing mouth sores or ulcers, more cavities or noticing any plaque¬† growth (like white patches) on the tongue, it is safe to assume that your mouth is able to prevent an excessive infiltration of these “bad bacteria” or other microogranisms. There is no reason to assume that all your good bacteria are wiped out after one course of antibiotics because it is not as sensitive as the bacteria in the bowels or within the vagina. The benefit of probiotics in this situation is questionable and we will not delve further into this scenario.

Bad breath may also be a consequence of pathology elsewhere in the body. Tonsillitis, postnasal drip, sinusitis, a lung abscess and even liver problems can also contribute towards it. Many gastrointestinal conditions may also contribute to this odor which will be more evident when you belch. The one issue that is worth considering in this case is the bridge that you recently had inserted. There may be a gap between the bridge and the gum where food particles will lodge and create a perfect environment for bacteria to thrive. Normal brushing may not be sufficient to reach these food particles and flossing this area is not easy either. A good mouth rinse can help to some degree. Speak to your dentist and a doctor and allow them to do the necessary examination and tests to identify the cause of this bad  breath.

Please note that any information or feedback on this website is not intended to replace a consultation with a health care professional and will not constitute a medical diagnosis. By using this website and the comment service you agree to abide by the comment terms and conditions as outlined on this page

Ask a Doctor Online Now!