In-vitro study of surface changes in fixed orthodontic appliances following air polishing with Clinpro Prophy and Air-Flow

Abstract

Objective: Air-polishing devices (APDs) are used to clean and polish tooth surfaces. The objective of this study was to examine the effects of exposing orthodontic wires and brackets to different types of powder when using an APD.

Material and methods: Three different wire materials (steel, TMA, Ni-Ti) were polished using an APD (Air-Flow((R)) S1), Clinpro Prophy and Air-Flow((R)). The exposure times were set at 5 and 10 seconds, the application distance at 2 and 4 mm. The wires were then measured for friction. The unpolished sections of the wires were used for control purposes. In a qualitative analysis, the brackets (steel, ceramic and plastic) were exposed for 5 s, 10 s, 30 s und 60 s from a distance of 2 mm using Clinpro Prophy and Air-Flow((R)). The polishing effects were then observed using a scanning electron microscope.

Results: The unpolished TMA wire exhibited greater friction (1.22 N) than the Ni-Ti (0.82 N) and the steel wire (0.97 N). Polishing resulted in a 2.5% increase in friction on average (p = 0.004). There was no evidence of a change in the ceramic bracket surfaces. When the Air-Flow((R)) device was used on steel brackets for longer exposure times, the result was a slight roughening of the surface. The plastic brackets exhibited changes that became more obvious after use of the Air-Flow((R)) device.

Conclusions: The surface changes in archwires and brackets caused by air-polishing devices when applying the Clinpro Prophy and Air-Flow((R)) powders can be considered as marginal overall. When the adjacent periodontium is intact, both powders are equally suitable, although the Air-Flow((R)) powder is somewhat more effective due to its greater abrasiveness. When using plastic brackets, Clinpro Prophy proved to be the powder of choice, thanks to its low abrasiveness.