Hi. Welcome to Healthcaremagic. I read your query. Inflammation of gums can be due to several reasons. Just check for any swelling or pus in that area or cavity in any near by tooth. If so, you need to visit denrist for its treatment. As you mentioned using baking soda. Its has good abrasive action and raise pH of mouth inhibiting bacteria but at times it can also cause gum inflammation. I suggest you to use a good toothpaste with baking soda rather then raw soda. Maintain good oral hygiene. If there is any plaque or calculus deposits, get oral prophylaxis done. Brush twice a day. Uss mouthwash. Do warm saline rinses. You can use Lidocaine oral gel on gums before eating. This will reduce burning sensation. Take good diet, multivitamin and minerals, spacially vitamin c, a, iron. Massage your gums with a gum paint. If inflammation persists or worsens, see a dentist. Hope the answer helps you. Thank you!