The 12 year old boy reported with increased overjet, mandibular incisors irregularity, hyper active mentalis muscle and deepening of mentolabial sulcus because of the abnormal lower lip sucking habit. Orthodontic treatment was started with a lip bumper appliance to break the lip sucking habit and continued with fixed orthodontic mechanotherapy. The lip bumper appliance therapy resulted in elimination of lower lip sucking habit and improvement in the lower incisors inclination.