Step 1 : Part 1 ( Localized or Generalized ) : 
- Generalized : if an abnormal appearance affects all the osseous structures of the maxillofacial region , Generalized disease mechanisms , are considered.
For example : Osteopetrosis is one of the Generalized lesion . (more examples)
- Localized : If the abnormality is Localized , one considers whether it is unilateral or bilateral .
For example : Radicular Cyst is one of the Localized lesion.
For example : Fibrous Dysplasia is one of the Localized lesion and commonly is unilateral .
For example : Paget’s disease is one of the Localized lesion and is always seen bilaterally in the jaws .
For example : Cherubism is one of the Localized lesion and is always seen bilaterally in the jaws.(more examples)