Mental nerve block. Artwork of a syringe being used to inject a local anaesthetic to numb the mental nerve, a procedure known as a nerve block. This nerve provides sensation for the frontal parts of the chin and the lower lip, as well as the gums for the front lower teeth. This nerve block allows minor surgery and dental work to be carried out on these areas. Here the injection is being applied into the buccal fold by the gum and near the mental foramen between the two premolars.