# Difference in Occlusal Contacts Obtained with Conventional Orthodontic and Clear Aligner Therapy: A Pilot Study

## TL;DR

This study compares how well traditional braces and clear aligners create stable bite contacts in young patients, finding that braces perform better in certain aspects.

## Contribution

The study provides new empirical evidence comparing occlusal contact outcomes between fixed orthodontic therapy and clear aligner therapy in growing patients.

## Key findings

- Fixed orthodontic therapy (FAT) produced higher total occlusal contact values in the occlusal contact surface (OCS) compared to clear aligner therapy (CAT).
- FAT showed fewer anterior contacts in OCS, NOCS, half-mm, and one-mm measurements compared to CAT.
- FAT resulted in higher contacts specifically at the second premolar tooth compared to CAT.

## Abstract

Background/Objectives: The achievement of stable and functional occlusal contacts represents a key objective of orthodontic treatment, particularly in growing patients. Evidence comparing the effectiveness of these two modalities in establishing adequate occlusal contacts in growing patients remains limited. This study aimed to evaluate and compare occlusal contact characteristics following clear aligner therapy (CAT) and fixed orthodontic therapy (FAT). Methods: Twenty-four growing patients (<18 years with permanent dentition) were included in the study and divided into two groups: 12 patients treated with fixed appliances and 12 treated with clear aligners. Post-treatment digital dental scans were analyzed to assess occlusal contacts. Contacts were calculated as the minimum distance between upper and lower arches using a color-map analysis. The following outcomes were evaluated: Maximum Contact Point (MCP), occlusal contact surface (OCS, ≤50 μm from MCP), near occlusal contact surface (NOCS, ≤350 μm), half mm (≤0.5 mm), and one mm (≤1 mm). Total occlusal contacts, antero-posterior distribution, left–right asymmetry, and single-tooth contacts were assessed. Results: The FAT group showed higher total occlusal contact values in OCS compared to the CAT group (p < 0.05). Statistical difference was also observed in the antero-posterior ratio, with FAT presenting fewer anterior contacts in OCS, NOCS, half-mm, and one-mm measurements (p < 0.05). No significant differences were found between groups in terms of left–right asymmetry or post-treatment single-tooth contacts, except for the second premolar, which exhibited higher contacts in the FAT group (p < 0.05). Conclusions: Fixed orthodontic treatment is more effective than aligners in achieving adequate occlusal contacts, with differences limited to tight contacts and antero-posterior occlusal distribution.