[Air-powder abrasive system for prosthetic clinical applications. Part 1. Characteristics of air-powder abrasive system and the effect of it on tooth surface]

The influence of air polishers on tooth enamel. An in-vitro study

This study compares the effect of 4 different air-powder abrasive devices (PWS) (Air-Flow-S1, Clean-Jet, Prophy-Jet 30, Prophy-Unit) on tooth enamel. Freshly extracted bovine teeth were partially embedded in polyurethane, the labial surface ground flat and highly polished. Subsequently the teeth were subjected to the spray from the air-powder abrasive device for 60 s or polished with a prophylactic paste (CCS 170, CCS 250 or Cleanic) for the same length of time. The effects of the different air-powder abrasive systems were tested under multiple adjustments of powder/air and water. In addition the effects of air-powder abrasive systems and prophylactic pastes on several dentin surfaces were measured. The resulting surface textures of the teeth were examined using laser optic profilometry. In this process multiple measurements of roughness as well as tooth erosion were determined. The Clean-Jet led to significantly rougher surfaces than the 3 prophylactic pastes at every setting. The Air-Flow-S1, Prophy-Jet 30 and Prophy-Unit resulted in enamel abrasion that was either less than that caused by the prophylactic pastes or not significantly different at every examined setting. The 3 polishing pastes removed 3.6 microns to 7.2 microns of enamel in 60 s. The Clean-Jet removed significantly more enamel at every setting per unit of time than the prophylactic pastes (up to 0.1 mm/min); therefore routine application of this device is not advised. Enamel abrasion by the Air-Flow-S1, Prophy-Jet 30 and Prophy-Unit was either less than that measured with the prophylactic pastes or not significantly different. However, the Air-Flow-S1 was more abrasive than Cleanic paste at maximum water adjustment. The Air-Flow-S1 removed 641.2 microns/min of dentin compared to 339.6 microns/min by the Prophy-Jet 30.