In vitro ëvaluation of abrasion resistance of condensable composite resins after toothbrushing. Wear and superficial roughness analysis.

Author(s)

Linda Wang

• Document type: Master's Dissertation
• Press: Bauru.
• Institution: Universidade de São Paulo (USP). Faculdade de Odontologia de Bauru (FOB/SDB)
• Defense date: 2001-03-02

Examining board members

Rafael Francisco Lia Mondelli; Eduardo Batista Franco; João Batista de Souza

• Advisor: Rafael Francisco Lia Mondelli

Abstract

"Condensable" composites resins are a category of posterior materials especially developed as an aesthetic alternative to amalgam. The aim of this research was to compare these materials by an "in vitro" abrasion test simulating toothbrushing. Solitaire (So), SureFil (Su), Alert (A), Prodigy Condensable (PC) and Filtek P-60 (P-60) were compared to two control groups, microfilleD Silux Plus (SP) and microhybrid Z100 (Z). Twelve samples of each material were prepared with 5mm in diameter and 3mm thick. The abrasion test was applied up to 100.000 cicles by an appropriate machine with soft bristles tips containing dentifrice solution and deionized water. The weight loss was detected by the differences between the initial (before toothbrushing) and the final weight (after toothbrushing) using a Sartorius analytical scale. The evaluation of surface roughness was observed by the difference between initial and final means after 5 readings in a Hommel Tester T1000 testing machine. The specimens were also analysed by SEM. The obtained results (ANOVA and Tukey) showed significant differences of weight and surface roughness between the tested materials. SureFil and Alert exhibited lower loss of weight (Su-0.38%; A-0.52%), Solitaire, Prodigy Condensable, and Silux Plus presented greatest wear(So-1.51%; PC-1.55%, SP-1.70%) while Z100 and Filtek P-60 showed intermediate loss ( Z-1.16%; P-60-1.31%). Differently to the others groups, Prodigy Condensable, Solitaire and Z-100 showed a decrease in surface roughness compared to the initial condition (-0.012mm,-0.047mm and -0.065mm respectively) which increased in the remainder groups (A) 0.073mm, P-60) 0.095mm, Si) 0.158mm and Su) 0.470mm). SureFil presented the lowest weight loss and the highest surface roughness variation comparing to the other tested resins. There was no correlation between wear and surface roughness. The SEM results were in accordance to those obtained by the Hommel Tester T1000 testing machine. "condensable" composites resins showed the same behavior compared to the microhybrid Z100 control resin. (AU)