California RDA Written Practice Exam 2025 – Full Prep Guide

The first step in trimming a model is to identify the area of work, which is typically the mandibular arch since it is the more stable arch. This provides a firm foundation for the maxillary arch to be trimmed and ensures a stable articulation. Trimming both models simultaneously or starting with neither of them would likely result in an inaccurate and unstable articulation. Therefore, it is recommended to begin trimming the maxillary model first to achieve the best results in trimming and articulation.