Dwarf Azalea Very Leggy

I have a dwarf azalea that has got very leggy, leaving the centre of the shrub bare. This is because the branches have become top-heavy with leaves.
What is the best solution for this? To give the plant a good shape.

 

I've had an idea that has worked for me before. I shall dig a large hole and bury the centre of the bush with only the green leaves above ground. It's worked for me before with different bushes. I'll give it a try.