Effects of Toothbrush Hardness on in vitro Wear and Roughness of Composite Resins

Abstract

Aim: To investigate and compare the effects of toothbrushes with different hardness on abrasion and surface roughness of composite resins. with standardized calcium carbonate slurry in a multistation testing machine (2N load, 60 Hz). After each of five cycles with 10k brushing strokes the wear depth and surface roughness of the specimens were determined. After completion of 50k strokes representative samples were inspected by SEM. Data were treated with ANOVA and regression analyses (p < 0.05). Materials and methods:Results: Abrasion of the composite resins increased linearly with increasing number of brushing cycles (r 2 > 0.9). Highest wear was recorded for VEN, lowest for VED. Hard brushes produced significantly higher wear on VEN and VEP, whereas no difference in wear by toothbrush type was detected for VED. Significantly highest surface roughness was found on VED specimens (Ra > 1.5 µm), the lowest one on VEN (Ra < 0.3 µm). VEN specimens showed increased numbers of pinhole defects when brushed with hard toothbrushes, surfaces of VEP were uniformly abraded without level differences between the prepolymerized fillers and the glass filler-loaded matrix, VED showed large glass fillers protruding over the main filler-loaded matrix portion under each condition. Conclusion:Abrasion and surface roughness of composite resins produced by toothbrushing with dentifrice depend mainly on the type of restorative resin. Hardness grades of toothbrushes have minor effects only on abrasion and surface roughness of composite resins. No relationship was found between abrasion and surface roughness.Clinical significance: The grade of the toothbrush used has minor effect on wear, texture and roughness of the composite resin.

Effect of toothbrush/dentifrice abrasion on weight variation, surface roughness, surface morphology and hardness of conventional and CAD/CAM denture base materials

“…Kyoizumi et al 31) reported that the hardness of the toothbrush bristles, tuft density, and tuft material had minimal impact on the surface roughness of denture resins and that changes in the overall roughness depend on the denture material used. Therefore, the polymerization methods used and the materials' compositions are factors that can potentially affect the artificial ageing of denture bases.…”

Glass Fiber Reinforced Composite Orthodontic Retainer: In Vitro Effect of Tooth Brushing on the Surface Wear and Mechanical Properties

“…Previous studies also demonstrated that retainers made of FRCs without composite coverage have values of rigidity more similar to values of metal retainers, and this is a positive feature [21,22,24,25]. Finally brushing interferes with all restorative materials previously tested changing their mechanical properties [27]. Therefore, the data presented have the aim to test mechanical properties, maximum load and maximum bending stress, of covered and uncovered FRC, compare them to stainless steel, and evaluate eventual changing after tooth brushing.…”

“…Previous authors demonstrated that, increasing the number of brushing cycles, the abrasion of composite resins increased in a linear way [27]. There are no studies evaluating force levels of FRCs bonded with a spot technique simulating a different tooth brushing entity.…”

Effect of Ultra-Soft and Soft Toothbrushes on the Removal of Plaque and Tooth Abrasion

“…Dentists recommend regular toothbrushes or soft toothbrushes over hard toothbrushes, which can potentially damage the gingival and oral mucosa. However, customers choose bristle hardness based on their personal preference 24) . Although it is generally reported that soft toothbrush cause less abrasion than hard toothbrush 25,26) , some studies have reported otherwise 27,28) .…”