An 11 year old female patient complains that her lips remain open and gums can be seen. Extra-oral examination reveals a short upper lip, whereas the intra-oral examination shows normal inclination of the incisors. Which of the following statements regarding this patient's chief complaint is false?
High-Yield Explanation
Growth of the Lips
The lips trail behind the growth of the jaws prior to adolescence, then undergo a growth spurt to catch up. Because lip height is relatively short during the mixed dentition years, lip separation at rest (often termed lip incompetence) is maximal during childhood and decreases during adolescence. Because the lips move downward relative to the lips and teeth during adolescence (and continue to do so as the face ages), what looks like too much display of gingiva prior to and in adolescence can look perfectly normal in a young adult.
Contemporary orthodontics, William Proffit, 4th edition page 47