This research investigates the development of a computational optimization framework for orthodontic aligner structures based on three-dimensional finite element modeling. The primary focus is on the methodological formulation and adaptation of topology and shape optimization techniques to aligner-type geometries, rather than on immediate clinical application or experimental validation. In previous work, a combined topology and sizing optimization framework was developed to optimize the structural design of hand orthoses [1]. In the present study, we extend this methodology and introduce further improvements. Topology optimization is explored to determine optimal material distribution under representative mechanical loading conditions, with particular emphasis on multi-objective optimization, including compliance minimization and reduction of maximum von Mises stress. Furthermore, multi-material topology optimization is considered to enable spatial tailoring of mechanical properties, supporting the design of aligners with locally differentiated stiffness and flexibility. In addition, constrained shape optimization is examined as a means to refine aligner geometries to improve stress distribution and structural efficiency while preserving clinically required fit conditions derived from dental scans. The outcome of this work is intended to be a robust, FEM-based optimization methodology that establishes a foundation for future implementation, application-specific design refinement, and experimental validation as the project progresses.