Does Tetracycline work for oral abscess?

Yes. Tetracycline is a broad spectrum antibiotic used in the treatment of dental bacterial infections. Tetracycline has a natural tendency to concentrate in the gingival fluids around the teeth so it is often used to treat gingivitis and gum disease.

You will find more information on the care of dental abscesses at https://www.drugs.com/cg/dental-abscess-aftercare-instructions.html