Toothbrush/ abrasion rates of modified glass ionomer restoratives in-vitro

Abstract

Modified glass ionomer restoratives are employed in conservation of abrasion cavities, and hence the characterisation of toothbrush abrasion is clinically important. The aim was to evaluate this parameter, for; resin, metal, and polyphosphonate modified glass ionomers, compomer, experimental composite and Perspex as control. Groups (n = 5) of cylindrical specimens (6mm<p x 12 mm) were fabricated in split metal moulds according to manufacturers instructions. Subsequently, specimens were conditioned in H20 for 24h at 37°C. A 4 Station brushing machine was used where the tooth brush heads (Oral 8Thl 40) were driven in a linear reciprocating action across the cylindrical surface of the test specimens. A dentifrice paste was prepared according to BS 5136 (1981). Specimens were subjected to a total of 80,000 brush strokes, and their mass was determined (to 10 -. g) after each 10,000 strokes. They were repositioned identically. Wear volume (calculated via density) was significantly different at (P <0.001) between the materials. Variable mean volume rates were apparent, the polyphosphonate and metal modified Glass ionomer exhibited the least, whereas the compomer showed the highest. Perspex did not demonstrate lowest wear volume after 20,000 strokes.