Results (
Thai) 1:
[Copy]Copied!
Ceramics also are gaining importance in the field of orthodontics ithe aligning of teeth that are crooked and out of place). To align teeth. an orthodontist cements a bracket onto each tooth and stretches a metal wire across the brackets to apply a steady pressure to push the teeth into place. The brackets traditionally have been but the bright metal is so readily metal. visible that some people are reluctant or embarrassed to have orthodontic braces. Initial attempts to replace the metal brackets with ceramics weren't successful. The stress caused when the orthodontist cinched up the wire was too great, and the ceramic usually broke. However, during the early 1980s, sapphire brackets were successfully introduced, and soon translu- cent polycrystalline alumina brackets followed. These ceramic braces, which are much less visible than metal braces, are now highly popular.
Being translated, please wait..
