The courts have had difficulty in defining the difference between “ordinary” negligence and “gross” negligence. But they do recognize a difference.

Gross negligence evinces a reckless disregard for the rights of others or smacks of intentional wrongdoing. In other words, gross negligence is an act or omission of an aggravated character, as distinguished from the failure to exercise ordinary care.  

As you can  imagine, if you are charged with gross negligence OPMC feels that you have committed an egregious act and they will seriously be considering  suspending your license to practice.