Background:
Diastema between maxillary anterior teeth may affect the smile, for that reason patients nowadays more and more often request a diastema closure procedure.

Aim of the study:
To investigate the differences in the width-to-length ratio of maxillary anterior teeth in patients with and without diastema.

Material and methods:
The study was conducted on Tunisian individuals (n=109) divided into two groups: the study group with diastema (n=50) and the control group without diastema (n=59). A digital vernier caliper was used to measure the length and width of maxillary anterior teeth on plaster models. The width was measured from mesial and distal contact points of the tooth on a line perpendicular to the long axis. The length measured the longest distance from the cervical margin to the incisal edge on a line parallel to the long axis. SPSS software was used to calculate the width-to-length ratio for each tooth and to analyze the data.

Results:
Statistical analysis showed that there is no significant difference of width to length ratio of maxillary anterior teeth in patients with or without diastema (left canine: P=0.251; left lateral incisor: P=0.916; left central incisor: P=0.097; right central incisor: P=0.711; right lateral incisor: P=0.879; right canine: P=0.788). The level of significance was set at 0.05.

Conclusions:
The width-to-length ratio given in this study may serve as guidelines for treatment planning for the diastema closure procedure.