What tool is not necessary when fitting a permanent adhesive bridge?

When fitting a permanent adhesive bridge, the use of a dental forceps, dental mirror, and cement applicator are essential tools. The dental forceps may be used to hold the bridge in place during fitting, and the dental mirror helps provide visibility and access to the patient's mouth, allowing the dental professional to accurately position the bridge. The cement applicator is crucial for applying the adhesive material necessary to secure the bridge to the teeth.

In contrast, an acrylic trimming bur is not required for this procedure. This tool is primarily used for adjusting and shaping acrylic materials, which is not part of the process of fitting a permanent adhesive bridge. The bridge itself typically does not require adjustments with a trimming bur during the fitting process as the pieces are already fabricated to match the patient’s dentition. Therefore, the acrylic trimming bur stands out as the tool that is not necessary when fitting a permanent adhesive bridge.