Comparison of Patient-Reported Comfort Between Two Clear Aligner Trimming-Line Designs: A Split-Mouth Study

* The trimming-line design of clear aligners (supragingival versus juxtagingival) is a routine clinical decision whose influence on patient-reported comfort has not been established; available evidence on aligner comfort derives almost exclusively from comparisons with fixed appliances. * This observational, cross-sectional study compares two clear aligner trimming-line designs with respect to patient-reported comfort: a supragingival design, whose edge rests on the marginal gingiva, and a juxtagingival design, whose edge follows the gingival contour without covering it. Because the two designs sit differently against the gingival soft tissue, they may be experienced differently during wear. * Participants are patients already wearing one trimming-line design on one dental arch and the other on the contralateral arch; each participant thus serves as their own control. After a minimum of four weeks of wear, participants complete a 20-item questionnaire once, rating the frequency of defined oral experiences for the maxillary and mandibular arch separately on a three-point ordinal scale (0 = none, 1 = occasional, 2 = frequent). * The questionnaire is anonymous; the design worn on each arch is identified from which of two identical forms a participant completes. Responses for the two designs are compared within each participant. The study evaluates whether trimming-line design is associated with differences in patient-reported comfort.

NCT Number	NCT07660809
Lead Sponsor	George Emil Palade University of Medicine, Pharmacy, Sciences and Technology of Targu Mures
Conditions	Patient Comfort, Malocclusion, Oral Health
Enrollment	70 participants
Start Date	2026-07-01
Primary Completion	2026-08 (estimated)
Study Completion	2026-08 (estimated)
Updated on ClinicalTrials.gov	2026-07-06