Department of Prosthodontics, University Hospital Heidelberg, Heidelberg, Germany.
J Oral Rehabil. 2014 Apr;41(4):314-22. doi: 10.1111/joor.12139. Epub 2014 Jan 22.
The purpose of this study was to evaluate enamel wear caused by monolithic zirconia crowns and to compare this with enamel wear caused by contralateral natural antagonists. Twenty monolithic zirconia crowns were placed in 20 patients requiring full molar crowns. For measurement of wear, impressions of both jaws were made at baseline after crown cementation and at 6-month follow-up. Mean and maximum wear of the occlusal contact areas of the crowns, of their natural antagonists and of the two contralateral natural antagonists were measured by the use of plaster replicas and 3D laser scanning methods. Wear differences were investigated by the use of two-sided paired Student's t-tests and by linear regression analysis. Mean vertical loss (maximum vertical loss in parentheses) was 10 (43) μm for the zirconia crowns, 33 (112) μm for the opposing enamel, 10 (58) μm for the contralateral teeth and 10 (46) μm for the contralateral antagonists. Both mean and maximum enamel wear were significantly different between the antagonists of the zirconia crowns and the contralateral antagonists. Gender and activity of the masseter muscle at night (bruxism) were identified as possible confounders which significantly affected wear. Under clinical conditions, monolithic zirconia crowns seem to be associated with more wear of opposed enamel than are natural teeth. With regard to wear behaviour, clinical application of monolithic zirconia crowns is justifiable because the amount of antagonistic enamel wear after 6 months is comparable with, or even lower than, that caused by other ceramic materials in previous studies.
本研究旨在评估整体氧化锆冠引起的牙釉质磨损，并将其与对侧天然牙的牙釉质磨损进行比较。将 20 个整体氧化锆冠放置在 20 名需要全磨牙冠的患者中。为了测量磨损，在牙冠粘固后和 6 个月随访时，通过印模分别获取上下颌的印象。通过石膏代型和 3D 激光扫描方法，测量了牙冠、天然牙和对侧天然牙的牙尖窝接触区的磨损均值和最大磨损值。使用双侧配对学生 t 检验和线性回归分析来研究磨损差异。氧化锆冠的平均垂直磨损量（括号内为最大垂直磨损量）为 10（43）μm，对颌牙釉质的磨损量为 33（112）μm，对侧牙的磨损量为 10（58）μm，对侧牙的磨损量为 10（46）μm。牙釉质的平均和最大磨损值在氧化锆冠的对颌牙和对侧牙之间均有显著差异。性别和夜间（磨牙症）咀嚼肌的活动被确定为可能的混杂因素，显著影响了磨损。在临床条件下，整体氧化锆冠似乎会导致与天然牙相比，对颌牙釉质磨损更多。关于磨损行为，整体氧化锆冠的临床应用是合理的，因为 6 个月后对颌牙釉质的磨损量与之前研究中其他陶瓷材料的磨损量相当，甚至更低。
