Biomechanical Evaluation of Force Loss and Simulated Tooth Movement in Maxillary Orthodontic Mesial Sliders: An In Vitro Pilot Study

Skeletal-anchored mesial sliders are increasingly used for molar mesialization, yet their mechanical behavior has not been compared under standardized conditions. This in vitro pilot study evaluated four slider designs (BENEfit® Beneslider [BB], TADMAN Beneslider [TB], IZE Slider [IO; OrthoLIZE GmbH], Slider on Minipin [SO; OrthoLIZE GmbH]), each combined with elastic chains (-C) or NiTi springs (-S), to characterize force loss, mesial movement, and associated mechanical side effects using an experimental biomechanical measurement system. Using repeated measurements on one specimen with 1 N of applied force, three-dimensional tooth movements were recorded across 200 simulation steps per run. The sliders showed design-dependent mechanical patterns: IO sliders produced the smallest sagittal movements (IO-C: −0.84 mm [0.05], IO-S: −0.79 mm [0.02]) and the highest force loss (IO-C: 88.1% [2.1], IO-S: 89.8% [0.3]), whereas BB-S and TB-S generated larger mesialization distances (BB-S: −3.55 mm [0.53], TB-S: −3.46 mm [0.08]) with lower force loss (BB-S: 42.8% [9.2], TB-S: 21.1% [2.9]). Translational deviations remained small, while rotational effects were more pronounced. These findings represent mechanical tendencies of the tested configurations under idealized conditions and do not account for biological variability, periodontal compliance, or patient-specific factors. As such, the results cannot be generalized to clinical performance but provide preliminary reference data. Expanded investigations using multiple specimens, biological modeling, or finite element analysis will be necessary to determine how these mechanical patterns translate into clinical tooth movement.