Can dutasteride cause changes in bone due to lack of alpha 5 type 1 on bone androgen receptors?

No, this should not negatively impact your facial bones.  I suggest seeing a hair loss expert now to evaluate and go over your condition and provide you information about your best treatment options. There are great non-invasive options like prp/progesterone and/or hair transplantation. See an expert. Best, Dr. Emer

The inhibition of 5 alpha reductase should not affect facial bones in a 20 year old. Dutasteride is not FDA nor Health Canada approved for hair loss. Its long half life requires consultation with a knowledgeable physician to review side effects including mood, fertility issues, sexual issues, gynecomastia, fatige, muscle changes and weight gain. 
Be careful what you read in this area (re bone changes) as many concepts are only hypotheses with no actual proof.