Is a dental bone graft absolutely necessary for me? (photo)

If the dentist is recommending a certain type of bone graft then there is a reason for it. Not in all clinical situations will synthetic bone work. Your decision of not needing a bone graft on the top is not the correct way to approach this as it is based a on clinical examination and clinical opinion by a doctor. If the dentist or doctor recommends a graft there is a reason for it and should be adhered to for the best long term success of any planned procedure.

I agree, bone grafting is necessary at both sites in which you are looking to have teeth replaced by implants in the future. The grafting in the upper left quadrant would include a sinus lift procedure. Hope this helps. 

Lucidfetus
If you are planning on having an implant on upper left and lower right, then you definitely need bone grafting prior to implant placement.  There don't seem to be adequate amount of bone for an implant to be placed.

I see teeth out of alignment, partial bite collapse in addition to your missing teeth. Although I do not have all the information I would like to answer your question. Once the alignment of your teeth is addressed or eliminated as a long term problem, besides replacing your lost teeth with implants, you also have the option of fixed bridgework to replace these teeth.  If you have questions about different alternatives and the long term health of your mouth and teeth, I would get the opinion of a good general dentist who emphasizes preventive dentistry and who restores missing teeth with both fixed bridgework and implants without prejudice to which is best before he sees you and knows all the details.

Look what happened on the other side ,need to do something fast,actually implant setting and bonegrafting will be a great idea. On the uppet side is a sinus lift and bonegrafting to preserve the integrity of that area,but if you arr not comfirtable with your dr, change but you need to do something right away,and synthetic materials will also work.

Your dentist is correct, grafting is needed and the materials suggested are the only ones that will work.  While the tissues originated from another human or animal, it is only temporary.  Your body will replace the foreign materials with YOUR bone, so within 6-12 months, only bone from YOU will remain.