BMC oral health, vol.24, no.1, pp.1533, 2024 (SCI-Expanded)
Abstract
Background The clinical performance of dental materials can be predicted via artificial aging approaches. The
bracket bonding procedure may cause irreversible alterations to the enamel surface. The aim of this study was to
introduce a novel artificial aging protocol and evaluate its effect on the discoloration of both bracket-bonded and
unbonded teeth while also comparing the effects of four orthodontic adhesives on enamel color and whiteness.
Methods One hundred permanent lower incisors from humans were randomly divided into five groups, each
including 20 specimens. The lower incisor metal brackets were bonded to the teeth via four different orthodontic
adhesives (Transbond XT, Kurasper F, Bisco ORTHO, and Light Bond), and a control group was established. To simulate
the cumulative effects of aging on the oral cavity, all the samples were subjected to mechanical cyclic loading (50,000
cycles), hydrothermal cycling (10,000 cycles), or exposure to stained beverages (25 days). A colorimeter device was
used to measure the color of the teeth before and after testing. Statistical differences were calculated via one-way
analysis of variance (ANOVA) and Tukey’s test.
Results The combined aging protocol resulted in statistically significant and clinically unacceptable differences in
tooth color alterations and whiteness index values across all groups (p < 0.05). The control group presented the least
significant discoloration, whereas the bracket-bonded groups presented greater discoloration. Furthermore, there
were statistically significant differences among the bracket-bonded groups (p < 0.05).
Conclusions The combined artificial aging protocol can be employed to simulate the macroenvironmental
conditions of the oral cavity in laboratory investigations. The composition of the orthodontic adhesive also influences
the severity of tooth discoloration.
Keywords Artificial aging, Tooth color, Discoloration, Orthodontic adhesive