ABSTRACT
Aesthetic is a major factor in accepting the removable prosthesis by the patient, and labial aspect of anterior teeth plays an important role in this regard. Therefore evaluating possible determinants of shape of anterior teeth is important. This study evaluated the predictive value of the facial shape determined with three different landmarks settings, in determining central incisor shape. This diagnostic clinical trial was performed on 120 participants. Photographs of the participants were taken in Normal head position; images of central incisor of each participant also were taken. Facial outline was determined as oval, triangular, and square, based on three landmarks settings with different upper points: glabella, eye brow, and forehead outline. Teeth labial outline was as well determined as oval, triangular, and square. Diagnostic value of facial shape in determining tooth shape was evaluated. The role of associated factors was evaluated using chi-square test. The positive prediction values of face shapes square, oval, and triangular were 34%, 34.7% and 33. 3%, respectively. It seems that the face shape is not an appropriate factor in determining the shape of prosthesis central incisors, and other indicators are necessary to be investigated