Influence of masticating cycles and chewing patterns on inadvertent enamel wear caused by zirconia brackets

Abstract

Little information is available about enamel wear caused by zirconia brackets, an inadvertent side effect of orthodontic treatment. The purpose of this study was to examine potential enamel damage induced by contact with zirconia brackets. Sliding and impact wear simulations were performed using bovine enamel specimens positioned at a 25˚slant to a zirconium ball to determine wear behaviour. Different chewing patterns, tapping and grinding, were simulated. Specimens were profiled using confocal laser scanning microscopy, and the mean maximum depth and surface roughness were measured. Scanning electron microscopy was also performed. The mean maximum depth of wear values differed according to the number of mastication cycles, with a higher number of cycles producing higher depths of wear. The facet wear depth was significantly greater with the tapping pattern than with the grinding pattern. Scanning electron microscopic observation of the wear facets revealed that surface textures at the edges were rougher than those at the centre of all facets. The results of this study indicated that enamel wear was induced by contact with zirconia brackets during the early period of mastication, and that the patterns and number of cycles of mastication affected the wear progression of enamel.

Fracture toughness and hardness of in‐office, 3D‐printed ceramic brackets

“…35,36 On the other hand, the alumina abrasive potential to antagonist teeth becomes clear when the enamel hardness of enamel is considered, which is 8-10 times less than the ceramic brackets. 37 This is a well-known iatrogenic side effect of ceramic brackets in general 38,39 which may be further enhanced when alumina is the material of choice. Patients with increased deep bite and bruxism should not receive alumina brackets in the lower arch since these are known to cause abrasion.…”

Dimensional Accuracy, Mechanical Property, and Optical Stability of Zirconia Orthodontic Bracket

“…This evolution has fueled an increasing interest in employing zirconia in the manufacture of orthodontic brackets, surpassing the constraints of conventional alumina ceramic brackets. 4,5,[13][14][15] However, the performance of orthodontic appliances fabricated by these novel zirconia variants remained unclear. Our study serves as a pioneering effort to bridge this gap by offering crucial insights into the performance of zirconia brackets.…”

“…3 To address these limitations, various innovative approaches have been proposed to develop advanced orthodontic brackets, with zirconia emerging as a promising material for enhancing mechanical properties owing to its remarkable toughness. 4,5 Zirconia brackets have been the subject of orthodontic research since the 1990s. 6 However, during this period, they did not demonstrate substantial improvements over alumina brackets in aspects such as frictional characteristics and aesthetic performance 7 .…”

“…12 Consequently, zirconia's emerging prominence in research and the creation of orthodontic brackets has become evident. 4,5,[13][14][15] However, existing literature has reported a direct correlation between yttria concentration, translucency, and mechanical strength in zirconia restorations. While an increase in yttria concentration can stabilize the cubic phase, resulting in greater translucency, it may concurrently diminish the mechanical strength.…”

Comparative Study of Transmission of 2940 nm Wavelength in Six Different Aesthetic Orthodontic Brackets

“…In contrast, monocrystalline brackets permit the passage of light, making these brackets basically clear [ 4 ]. Nowadays, there are zirconia brackets, which are considered ceramic brackets, but little information about them is available, and they need to be tested more [ 5 ].…”