Wednesday, September 26, 2012

Digital analysis of staining properties of clear aesthetic brackets

With more general dentists doing orthodontics this is important to know. MJ

Journal of Orthodontics vol. 39 no. 3 170-175 

Abstract

Objective: To analyse the staining properties of clear orthodontic brackets using a digital analysis.
Design: In vitro, laboratory study
Material and methods: A total of 500 tooth-coloured brackets from 10 brands (five ceramic and five plastic) were investigated. The cumulative discolouring effect of staining agents (tea, coffee, curry and red wine) were analysed at two consumption levels: light and heavy, based on a 6-month period of exposure. Study group brackets were immersed in the agents consecutively at 37°C. The control group was only exposed to artificial saliva. Samples were analysed digitally to obtain L*, a* and b* (lightness, red-green and yellow-blue) colour readings. Using these values, total colour change (ΔE*) at each level was also calculated. Three-way analysis of variance (ANOVA) test was used for statistical comparisons.
Results: L* and b* colour parameters showed significant differences (P<0 and="and" between="between" bracket="bracket" consumption="consumption" different="different" em="em" exposure.="exposure." groups="groups" however="however" levels="levels" of="of" the="the" type="type">a
* value only differed between bracket groups (P<0 according="according" em="em" the="the" to="to">E* values, ceramic brackets had less colour change than plastic brackets at the end of phase 1 for both the study and control groups. However, as consumption time increased, the rate of colour change decreased for the plastic brackets. In general, ceramic brackets demonstrated much more resistance to staining agents than plastic brackets.
Conclusions: Both plastic and ceramic brackets showed changes in colour when exposed to heavy consumption of staining agents, with plastic brackets being the most affected.

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