The objective of the work was to evaluate changes in the shape of the dental arch after treatment with fixed and removable devices without extraction. Statistical analysis of the dimensions and shape of the dental arch was implemented before the onset and after termination of orthodontic treatment and during a check-up examination after an interval of 3–5 years. The plaster models of dental arches obtained by means of a scanner on the computer screen were processed by digitalization within the framework of thr Kefalo programme. Segmental analysis was made, dental discrepancy in the dental arch values of Bolton’s index were assessed and an ideal occlusion curve in the frontal and premolar section of the mandible was suggested. The presented paper is based on a study by the authors where the shape and dimensions of the upper and lower dental arch of a selected sample of the junior adult population was evaluated [1].

        Key words: treatment with fixed and removable devices – dental arch – occlusion curve