Paget's disease is a chronic disease that affects how the body breaks down and rebuilds bone tissue. Paget's disease can be active or inactive, depending on whether the bone formation process goes too quickly or normally.
Inactive Paget's disease
In inactive Paget's disease, bone tissue is being broken down and rebuilt at a normal speed. This most often occurs when you are using medication to slow the bone growth. The inactive state may continue even after you stop taking medication. This is called remission.
Active Paget's disease
Active Paget's disease has three stages. They are:
Bone pain may occur in any of the stages.
WebMD Medical Reference from Healthwise