The Screw Head of the Dental Implant Broke Off. Is This Common? How Difficult to Fix?

The weakest link in any implant system is the small screw that attaches the implant abutment to the head of the implant. This screw can break yes but should not be considered a "common occurance." There are special tools made to remove a fractured screw from an implant. I've honestly never heard of a laser being used for this purpose and might in fact be contraindicated. This might be worth a second opinion.

I am not exactly certain what you mean by the "screw head". There is the healing abutment (placed after surgery while implant heals) and the prosthetic abutment (which is placed on the implant to support the new crown). If it is the prosthetic abutment that broke off and part of the screw is wedged or stuck in the implant body itself, it may be difficult or easy to remove depending on the skill of the dentist. Ask your dentist or seek out a PROSTHODONTIST (specialist in crown and bridge and implants) in your area to assist you to correct this problem. DO NOT LET YOUR DENTIST NOTCH ANYTHING. This may be irreversible and and destroy your implant forever. 

This is an extremely uncommon event in the hands of an experienced surgeon. This particular event is almost always due to one of two reasons. The first is lack of experience in placing dental implants. The reason the implant broke was because of too much torque placed on that particular implant. Whether it is from faulty implant (which is extremely rare if a legitimate implant brand was used, not a cut rate cheap implant company that the dentist used to save a few dollars) or a inexperienced dentist, too much torque was placed.  Removal is the only remedy. This usually needs to be done with a trephine bur. Using a laser against any metal object is tantamount to malpractice and is extremely dangerous.  I am curious as to what type of doctor placed this implant. The success rate would be excellent if removed  and replaced by a properly trained surgeon. Seek the help of a board certified Oral and Maxillofacial surgeon for help in this matter.  Beware of doctors that have only had a weekend course or two in dental implants. It takes several years of proper training to place implants safely,