Display of mandibular and maxillary anterior teeth during smiling and speech: age and sex correlations.

This study aimed to measure mandibular and maxillary anterior tooth display during smiling and speech and to evaluate correlation with age and sex. Ninety-four subjects were video recorded when smiling and when saying "ah" or "shesh." Anterior tooth display was measured using individual video frames. Average mandibular and maxillary anterior tooth display showed opposing trends. The former increased with age, had a tendency to be greater in men, and was greater during speech than during smiling. The latter decreased with age, was greater in women than in men, and was greater during smiling than during speech. Anterior dental esthetic evaluation, especially for the mandible, should include observation of speech.