Can i use salt water as mouthwash?

Yes: Salt water in a natural antiseptic and decreases inflation in open wounds. Short term use only especially if you have blood pressure issues and also because the rinse is slightly acidic and can etch enamel with long term use

Short term: Salt water mouthwash rinses are an excellent short term treatment when you have wounds in the mouth, for instance, when you’ve had teeth removed.Longer term, the salt water is acidic, so there would be a problem if you were to use it every day, it could erode the teeth, but is not necessarily abrasive to the teeth. It is the acidity of the salt water that could eat away and soften the enamel