Removing carious dentin using a polymer instrument without anesthesia versus a carbide bur with anesthesia

The authors describe a new rotary polymer instrument that selectively removes infected dentin. This instrument has the potential to prepare selected cavities without the need for local anesthesia (LA). Patient acceptance has not been investigated in a clinical trial.

In this open-label clinical study, the authors enrolled 20 subjects with two Class I carious lesions and randomly assigned them to receive one restoration with the polymer instrument and no LA and the second restoration with a carbide bur and LA. Both procedures were completed in one appointment. Subjects completed dental history, dental anxiety and situational pain questionnaires. At specific points during the procedure, subjects rated their perception of the intensity of cold, heat, pain, pressure, vibration, fear and anxiety. On completion of the restorative procedures and at 48-hour and one-week telephone contacts, subjects indicated which procedure they preferred.

During treatment with the polymer instrument, subjects indicated that they experienced slightly more pain, pressure, vibration and anxiety, but not more heat, cold or fear. Immediately after the procedure, 14 (70 percent) of 20 respondents (binomial test; P = .11) said that they would prefer having no LA and use of the polymer instrument for future dental work. The number of subjects indicating this preference increased to 15 (P < .05) at both the 48-hour and one-week contacts. One subject requested rescue LA during the polymer instrument treatment.

A significant number of subjects preferred the rotary polymer instrumentation with no LA to the carbide bur instrumentation with LA. They held this preference despite experiencing slightly, but reliably, more pain and pressure when treated with the polymer instrument.

A polymer (bur-like) rotary instrument with cutting ability limited to infected dentin can be used in Class I cavity preparations without the need for LA.