When loading a maxillary tray, where should you start placing the alginate?

When loading a maxillary tray with alginate, it is essential to start placing the material on the posterior side. This approach ensures that the alginate flows toward the anterior section as the tray is seated in the patient's mouth. By starting at the back, the material can adequately cover the posterior teeth and their contour, which is crucial for capturing an accurate impression.

Beginning at the posterior section also helps prevent air bubbles from forming, which can occur if loading starts in the anterior section. When the tray is inserted, the alginate will move forward due to the pressure and allow for a complete and dense impression of the dental arch, including the hard palate and the buccal vestibules. This method provides optimal coverage, ensuring that the impression captures all necessary anatomical features for proper diagnosis and treatment planning.