Matasa C G
Am J Orthod Dentofacial Orthop. 1999 Feb;115(2):158-65. doi: 10.1016/s0889-5406(99)70344-6.
The overall resistance to accidental blows of the many ceramic brackets that are sold today has not been explored. Facing a similar diversity, the eyeglasses industry has chosen to standardize the testing of lenses by subjecting them to the drop of a steel ball. By slightly modifying this test, 10 brands of ceramic brackets were examined. In most cases, the findings coincided with those found by other authors when duplicating debonding. Thus, polycrystalline ceramics with bulkier structures and glazed surfaces were found to be more resistant to impact than the monocrystalline brackets, the loftier real "twins," and the less dense attachments. Protruding tie wings and bases were liabilities, and domed configurations seemed to deflect the blows. Bulkier "single" designs alone did not offer a guarantee of impact resistance when not accompanied by an appropriate microstructure and a smooth surface. The ceramic brackets most resistant to impact were found to be 20/20 by American Orthodontics and Fascination by Dentaurum. Medium resistance was displayed by Lumina by Ormco, Allure III and Allure by GAC, Transcend 2000 and Transcend by Unitek/3M; the last was not as good as the other four. The least resistant were Illusion by Ortho-Organizers, Intrigue by Lancer Orthodontics, and Starfire TMB by "A"-Co. Probably because of its real twin design, the last bracket lends itself to the highest probability for accidental breakage. Although resistance to impact and accidental debonding is desirable from the point of view of treatment, the advantage should be weighted against the chance of enamel fracture. Indeed a weak bracket attached with a soft adhesive may be preferable when the chance of an increased exposure to accidental blows is probable. In such cases, the ceramic may take the brunt of the force, instead of the tooth.
目前市面上销售的众多陶瓷托槽对意外撞击的整体抗性尚未得到研究。面对类似的多样性情况，眼镜行业选择通过让镜片经受钢球掉落的方式来规范镜片测试。通过对该测试稍作修改，对10个品牌的陶瓷托槽进行了检测。在大多数情况下，检测结果与其他作者在重复脱粘检测时的发现一致。因此，发现结构更厚实且表面有釉的多晶陶瓷比单晶托槽、更高的真正“孪生”托槽以及密度较小的附件更耐冲击。突出的结扎翼和底座是弱点，圆顶形结构似乎能使撞击偏转。单独的更厚实的“单一”设计在没有合适的微观结构和平滑表面相伴时，并不能保证具有抗冲击性。发现最耐冲击的陶瓷托槽是美国正畸公司的20/20托槽和丹特伦公司的Fascination托槽。奥美科公司的Lumina托槽、GAC公司的Allure III和Allure托槽、优尼康/3M公司的Transcend 2000和Transcend托槽表现出中等抗性；最后一款不如其他四款。抗性最差的是正畸组织者公司的Illusion托槽、兰斯正畸公司的Intrigue托槽以及“A”公司的Starfire TMB托槽。可能由于其真正的孪生设计，最后一款托槽意外断裂的可能性最高。尽管从治疗角度来看，抗冲击和意外脱粘是可取的，但这种优势应与釉质骨折的可能性相权衡。实际上，当意外撞击暴露增加的可能性较大时，用软粘合剂附着的较弱托槽可能更可取。在这种情况下，陶瓷可能会承受主要的力，而不是牙齿。
