Question about which insurance should be billed?

My husband had a surgical procedure to remove a malignant tumor on the floor of his mouth. During this procedure his oral surgeon worked with the ENT surgeon and removed all his teeth as a precaution and part of his medical treatment. We learned that his dental insurance, rather than major medical, was billed for this service, maxing out the dental benefits for that year, and leaving us with a rather large bill from the oral surgeon. My question is should the oral surgeon have submitted this to the major medical insurance, as it was a medically necessary procedure that occurred during a surgery? The oral surgeon actually billed for each tooth removed as if it were a separate office call for each extraction, close to $150 per tooth. Another question, it has been over a year since this operation and billing, can I still ask the oral surgeon to request payment from the major medical insurance? Or am I stuck since I waited so long to take action on it? Any help or advice is greatly appreciated.
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Most services that are considered 'medical' should go to the medical insurance first and dental would apply as secondary (if at all). Sometimes they will cover all but the tooth removal. It depends on the exclusions of the plan. Has it been too long? Depends again on the exclusions of your insurance plan. You should contact your customer service and see what their timely filing guidelines are. Some have 1 year, 2 years or even specific months. Also, you can ask that because it was was sent into the Dental, if that could be considered timely filing (some plans may allow a filing with another insurance company proof of timely filing).
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