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 a claims as to the usefulness of head gear. They can reduce the risk of injuries and lacerasions 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 otherhand, 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 lower stakes sparring matches. Then the fighter starts taking punches instead of developing evasive manuvers 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 will be in for a very rude awakemimg due to the explosive nature of a real match, creating a string of losses. Additionally because the headgear is bigger adding more volume to the head, it creates a bigger easier targe to hit. Even though each landed strike might not be as hard, over the years the dammage they could begin to add up.