Brief Answer:
Restoration , Maintain good oral hygiene

Detailed Answer:
Hello XXXXXXX ,

Thanks for consulting Healthcaremagic .
This is Dr. Priyanka tiwari answering your query .

Read your query as you have decayed molar tooth this is said to be as deep occlusal cavity see what happened is caries in tooth can be due to some reasons like Due to poor oral hygiene ( improper brushing technique ) , Eating more sticky food , Dry mouth , Use of tobacco containing products or some medical condition like Diabetes .

I will suggest you to do some remedies to prevent caries :
-Maintain proper oral hygiene by brushing twice daily using soft bristle tooth brush .
- Use mouthwash regularly like chlorhexidine or Oraguard .
-Do warm saline rinses twice daily .
- Use interdental waxed floss to clean interdental region of teeth .

For decayed molar tooth I will suggest you to consult oral surgeon for visual examination of molar tooth and investigations Intra oral periapical radiograph of tooth discuss with your doctor if it can be restored then go for Restoration (filling) or Root canal treatment .

Hope I have answered your query .
If you have further query I will be happy to help.

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