Many morphometric studies show a sexual dimorphism in human teeth. We wanted to know whether it is possible to determine the sex of an individual if only the anterior teeth are visible. Fifty intraoral photographs showing the front tooth region of female and male individuals (age: from 7 to 75 years) were randomly arranged in actual size on a questionnaire. The lip region was covered in each case. Besides "female" and "male", one was also able to check "?" if undecided. The questionnaires were distributed to 50 expert test persons (dentists, dental technicians, dental assistants, and students of dental medicine) and to 50 laymen and were all returned for evaluation. Although the correct sex was recognized on single photographs to a maximum of 76%, it was incorrect in 69% on other photographs. Altogether, the statistical evaluation showed that in most cases, the sex was only recognized correctly by one half, and incorrect by the other half. It can be concluded that a sexual dimorphism of human teeth-although measurable morphometrically-could not be recognized visually on the basis of photographs of the front tooth region. Neither experts in the field of dentistry nor laymen were able to properly distinguish between male and female teeth.