Brief Answer:
Eruption bulge of wisdom tooth , inflammation.

Detailed Answer:
Hello XXXX

Thanks for consulting Healthcare magic.
This is Dr. Priyanka Tiwari answering your query.

I have read your query and understand your concern. As far as soft lump on jaw bone behind molar tooth is concerned this can be due to two possibilities -It can be Eruption bulge of wisdom tooth or due to inflammation in gum (gingivitis ) secondary to trauma or deposition of food debris in subgingival area of gums .
Can you upload image of soft lump that will be more helpful for me to arrive at conclusion and give you proper diagnosis? You have a feature to upload the image by yourself on the right side of this query page. Please utilize it. Alternatively, you can mail the images to YYYY@YYYY with subject line as 'Attention to Dr. Priyanka Tiwari'.

Based on detail provided I will suggest you some home remedies -
-Do warm saline rinses 3 to 4 times a day .
- Maintain proper oral hygiene by brushing and use chlorhexidine mouthwash regularly .
-You can apply ointment like stolin gum paint on soft lump.
- You can take medicine like Diclomol SP or Zerodol SP for pain and swelling by consulting with your local doctor.

Awaiting for picture to comment further .

Hope I have answered your query and this will help you .

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