This week I have consulted with 3 kids (7-9 years old) who have developed a severe lip biting habit. Often children are shamed for sucking their thumb, but replace this habit with sucking or biting their lower lip. The new habit is more socially acceptable but can create the same dental problems as thumb-sucking. The act of lip biting or sucking puts pressure on the lower teeth which will push them back and crowd them. At the same time pressure is applied on the upper teeth spacing them and pushing them forward. The result is a large overbite (overjet) which can only be corrected with orthodontic therapy. (braces and sometimes extractions).