Introduction: The diagnosis of scoliosis during orthodontic treatment is often attributed to orthodontic treatment, which may be a simple confounding factor. Do scoliotic patients require increased orthodontic treatment? Is the extent of their need for orthodontic treatment correlated with the severity of their scoliosis? Material and method: The authors conducted a comparative multicenter epidemiological study between a group of patients with a proven diagnosis of scoliosis objectified by the Cobb angle and a control group recruited from the general population. The endpoint was the Index Of Orthodontic Treatment Need (IOTN). The calculation of the number of subjects was made a priori. A statistical significance threshold of 5% was used for the statistical analysis. Results: In this study, 104 patients were included: 36 patients (10 boys, 26 girls) with an average age of 12.1 years (+/–2.3 years) in the scoliosis group (mean Cobb angle = 21°) versus 69 patients (20 boys, 49 girls) with an average age of 12 years (+/–2.7 years) in the control group. Patients with scoliosis have a significantly higher need for orthodontic treatment than the general population. The study did not correlate the severity of scoliosis with the increased need for orthodontic treatment. Discussion: Thus, the diagnosis of scoliosis during orthodontic treatment should not systematically result in the removal of the orthodontic appliance over-hastily held responsible for the scoliotic condition.