Bio-dental metrology optimum working conditions of polishing agents for better surface quality of tooth dentine surface. I. Water effect

ABSTRACT

Roughness on tooth surface is a very important factor in increasing the rate of the accumulation of deposits of both dental plaque and calculas. It is a rational procedure, following scaling and root planning instrumentation, to polish the exposed root surface to reduce surface roughness. In the presented paper an experimental work was carried out to investigate the effect of the following factors on the surface roughness and rate of wear at the root planed dentine surfaces, using Denesco webbed rubber polishing cup and water alone. [a] Speed of cup rotation [r.p.m.]. [b] Load applied [g]. [c] Duration time [seconds]. A total of 28 recently extracted adults' teeth were randomly selected for the experimental work in this investigation. The surface to be tested was scaled and planed by sealers and periodental curettes and then was flattened by lapping. Each tooth was embedded in a special mould. The surface roughness degrees were measured using Talysurf type 4 and Surface Roughness Meter. The amount of dimensional wear was measured by means of the Abbe vertical Metroscope. A special apparatus simulating the polishing tool was designed, manufactured and set-up in the Production Eng. Dept., Faculty of Eng., Alexandria University enabling the application of different applied loads [300 - 900 g] and different rotational cup speeds [185 - 1230 r.p.m.] for different duration periods up to 300 secs. Relations were achieved concluding with the optimum working conditions to give best surface qualities