Smile Arc is good indicator of dentolabial harmony and attractiveness. The number of teeth displayed has an impact on smiling. Smiles which show first molar to first molar are judged the most attractive. Thus the aim of our study was to assess the smile arc in Palestinian adolescents and the number of teeth displayed in smiling so that to determine the attractiveness of Palestinian smile. This study was conducted on Palestinian adolescents with a total of 851 subjects (446 males and 405 females) aged between 12 and 17 years. They were examined for the smile arc using computer software program. (Adobe Photoshop CS3, Japan) The results showed that 75.8% of the Palestinian adolescents examined had consonant smile arc. Flat Smile Arc was present in 19.2% and reverse smile arc was present in 5% of the population examined. Statistically significant difference was present between males and females considering the smile arc and teeth displayed during smiling (p<0.05). The only insignificance was for consonant smile arc and smile that displays first premolars. The results also showed the percentage of people displayed canines during smiling was 5.1%, first premolars was 16.9%, second premolars was 35.5%, first molars was 40.3% and second molars was 2.2%. Palestinian adolescents generally show an attractive smile considering the impact of the number of teeth displayed on smiling and percentage of population having consonant smile arc.

Keywords: Smile Arc, Adolescents