Hi,
From x-ray it seems you need root canal treatment first, 2 teeth are already treated but they have no crowns so you might loose tooth structure. You can have options like tooth colored crown for all teeth if it has proper support. For extra support post and core also be used. But we cant direct jump into conclusion by having just x-ray. You need clinical evaluation done and choose the treatment options available.
Next Steps
Kindly visit us at Dental Galaxy Pune for consultation or treatment http://dentalgalaxy.in/
Health Tips
Other alternative options available are- dental crowns, dental veneers, composite restoration