Im being referred to maxofacial as an xray showed a lighter grey than it should be..my dentist is unsure what it is..please help with advice?

"Lighter Grey": is not really a radiologic description, it doesn't convey any useful information. Do you have the specific findings from the xray report?

Guesswork: "Lighter Grey" indicates less bone density. It does not tell us where, size, duration, cause, artifact or actual finding. Thank your dentist for noticing this anomaly, whatever it is, and referring you to an Oral and Maxillofacial Surgeon for further evaluation.

Radiolucency: While experienced dentists are accustomed to viewing thousands of x-rays a year, we occasionally see something on the x-ray that although we don't think it's anything to be concerned about we want to be absolutely sure that we are not missing anything. At that point we refer to a specialist who may take a panoramic or CBCT (3D) image to confirm that there is no pathology present.

On the right track.: It's great that your dentist is noticing things that are out of the ordinary--many times things like that can be missed entirely. The answer to your question is the reason for a conversation with the oral surgeon. GO to the appointment; there's no better way to get that advice you're seeking.