Is the quality of occlusal contacts comparable after aligner and fixed orthodontic therapy? A non-randomized cohort comparison using computerized occlusal analysis during 6 months of retention

ABSTRACT

Objective

Less than ideal contacts have been reported following aligner therapy, but it is considered a transitory problem, spontaneously resolving with the phenomenon of settling. Methods: Thirty-nine orthodontic patients (14 treated with aligners; 25 with fixed appliances) were evaluated with a digital occlusal analysis system (T-scan™10), assessing Maximum Intercuspation contact simultaneity, symmetry, and relative force distribution at treatment completion and after 3 and 6 months.

Results

No significant differences in occlusal contact quality were found between groups at treatment completion or follow-up. The center of force moved posteriorly and remained stable after 3 months but was located more anteriorly in females (p = 0.01). One-third of patients (both groups combined) had marked contact force asymmetry even after 6 months’ retention. Conclusion: Occlusal contacts were comparable at completion of treatment with aligners or brackets and after 3–6 months of retention. Settling did not improve marked asymmetry in all patients.

KEYWORDS:

• Settling
• occlusion
• posterior occlusion
• T-Scan 10 System™
• center of force
• aligners
• fixed appliance therapy

Acknowledgments

The authors thank the clinical instructors who supervised the orthodontic treatment of patients presented in this study, notably Dr. HEK, Dr. M, Dr. RL, and CR.

Authors’ contributions

Dr. JCL, AM and RBK designed the study. Dr. CB collected data and wrote the first version of the manuscript. PR performed statistical analysis, critically reviewed conclusions and several manuscripts. Dr. JCL and RBK reviewed and modified data presentation, wrote the discussion, and updated references. All authors read and approved the final manuscript.

Disclosure statement

Dr JCL, Dr CB, PR and Dr AM declared no conflict of interest. Dr. RBK is a consultant to Tekscan, Inc, S. Boston, MA USA, but receives no monetary gain from sales of any Tekscan products

Additional information

Funding

This study was not funded by public or private funds, but the recording sensors were graciously provided by Tekscan, Inc, S. Boston, MA USA.