An ever increasing issue coming up in MMA Gyms and striking programs is whether or not the sparring should include headgear. There's arguments to both and it all depends on who is running the program.
There are claims as to the usefulness of head gear. They can reduce the risk of injuries and lacerations to the face. They can possibly reduces the effects of concussions and long term brain damage. Headgear can also serve as a learning tool allowing the fighter to take more chances and learn from his/her mistakes.
On the other hand, you have a few arguments suggesting the opposite. Headgear can give the fighter a false sense of security because shots are easier to block and not felt as hard. The fighter can develop bad habits due to the lower stakes of getting hit. Then the fighter can start taking punches instead of developing evasive maneuvers to avoid damage. This could also lead to long term brain damage due to a higher volume of lower impact blows over time. Eventually when the fighter steps into the ring, he or she can be in for a very rude awakening creating a string of losses. Additionally because the headgear is bigger, adding more volume to the head, it creates an easier target to hit. Over the years, the damage could begin to add up.