Since you got full mouth extraction so the chances of infection automatically increases if you don't take extra care of oral health. Ideally after an extraction, special care is needed only for a week or so but in case of full mouth extraction, healing is usually delayed so the patient should be extra precautious regarding his oral cavity.
Here are few of the tips:
Do warm saline gargles atleast thrice daily
Use anti bacterial mouthwash twice daily.
If in case of any pain or abnormal feeling don't hesitate to contact a dentist.
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