Choosing fixed appliances versus clear aligners in adults depends on several real-world treatment factors. The most important is the complexity of the malocclusion and the specific tooth movements required, especially torque control and anchorage. Fixed braces provide robust, predictable control over tooth movements, making them preferable when substantial root torque, vertical control, rotations, or bite adjustments are needed. Aligners can handle many cases well and are appealing for their removability and aesthetics, but certain movements—like complex torque, extrusion/intrusion, or precise occlusal changes—can be more challenging, sometimes needing attachments or alternative approaches. Patient compliance is also key: aligners require consistent wear to achieve the planned biology, so if a patient may struggle with adherence, fixed appliances reduce this risk. Aesthetics play a role, with many adults favoring the discreet appearance of aligners, though modern fixed appliances, including ceramic brackets, offer improved aesthetics. Cost is another consideration, as overall treatment expense can steer the choice in practice, depending on case length and complexity. Finally, the potential for interdisciplinary care matters; complex cases often benefit from collaboration with periodontists, restorative dentists, or surgeons, and fixed appliances can integrate smoothly into such plans.