During denture construction, the patient will attend for a trial insertion of the dentures with the teeth set in wax rims. Which one of the following instruments is used for fine wax adjustments at this stage?

The instrument used for fine wax adjustments during the trial insertion stage of denture construction is the Le Cron carver. This tool is specifically designed for shaping and sculpting wax, allowing dental professionals to make precise adjustments to the wax rims where the teeth are set.

During the trial insertion, it is essential to ensure that the wax rims not only fit properly but also create an accurate representation of the intended final denture shape. The Le Cron carver’s sharp edge and pointed tip allow for detailed carving and refining of the wax, enabling adjustments for aesthetics, function, and comfort based on the patient's feedback.

Other instruments mentioned, while useful in dental procedures, are not suited for this specific task. An articulator is primarily used to maintain the relationship of the dental arches and is not for fine wax modifications. A plaster knife is typically utilized for working with plaster materials rather than wax. Meanwhile, a wax knife, although it may seem appropriate for working with wax, is generally used for more general handling and shaping rather than the intricate detail required during the trial phase. Therefore, the Le Cron carver is clearly the best choice for this particular adjustment process.