Evtimovska Elizabeta, Masri Radi, Driscoll Carl F, Romberg Elaine
Baltimore College of Dental Surgery, Baltimore, MD 21201, USA.
J Prosthodont. 2009 Aug;18(6):479-83. doi: 10.1111/j.1532-849X.2009.00474.x. Epub 2009 Jun 3.
The aim of this study was to examine early changes in retentive values of implant overdenture attachments during multiple pulls.
Two implant attachment systems (Hader bar and clip, Locator system) were used in this study. The experimental groups were divided into yellow Hader clips, white Locator attachments, and green Locator attachments. Each group consisted of 21 matrix attachments. The attachments were placed into a custom-made acrylic resin block seated passively on another acrylic block containing a Hader bar or two Locator abutments with different angulations. Each attachment was subjected to 20 consecutive pulls using a universal testing machine. The peak load-to-dislodgement of the attachments after each pull was documented, and the percent reduction of the peak load-to-dislodgement was calculated. One-way ANOVA and Tukey's honestly significant difference test were used for data analyses. A p < or = 0.05 was considered significant.
There was a significant difference in the percent reduction in peak load-to-dislodgement between the attachments after the first pull (p= 0.005) and after the final pull (p= 0.0001). The yellow Hader clips exhibited the least percent reduction in peak load-to-dislodgement (6.50 +/- 3.59%) after the first pull, followed by the white Locator attachments (8.60 +/- 4.42%); the green Locator attachments exhibited the greatest reduction (11.05 +/- 4.94%).
The results of this in vitro study demonstrate that retentive values of the Locator attachments are reduced significantly after multiple pulls. Although this reduction might not be noticeable to the patient, it is recommended that the clinician place and remove the overdenture multiple times before delivery.
本研究旨在检测种植覆盖义齿附着体在多次牵拉过程中固位值的早期变化。
本研究使用了两种种植附着系统（哈德尔杆卡和Locator系统）。实验组分为黄色哈德尔卡、白色Locator附着体和绿色Locator附着体。每组由21个基质附着体组成。将附着体放置在定制的丙烯酸树脂块中，该树脂块被动地安置在另一个含有哈德尔杆或两个不同角度Locator基台的丙烯酸块上。使用万能试验机对每个附着体进行连续20次牵拉。记录每次牵拉后附着体的峰值脱位负荷，并计算峰值脱位负荷的降低百分比。采用单因素方差分析和Tukey真实显著性差异检验进行数据分析。p≤0.05被认为具有显著性。
第一次牵拉后（p = 0.005）和最后一次牵拉后（p = 0.0001）附着体峰值脱位负荷降低百分比存在显著差异。黄色哈德尔卡第一次牵拉后峰值脱位负荷降低百分比最小（6.50±3.59%），其次是白色Locator附着体（8.60±4.42%）；绿色Locator附着体降低最大（11.05±4.94%）。
这项体外研究结果表明，多次牵拉后Locator附着体的固位值显著降低。尽管这种降低对患者可能不明显，但建议临床医生在交付前多次放置和取下覆盖义齿。
