Department of Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
Department of Removable Prosthodontics, Faculty of Dentistry, Mansoura University, Mansoura, Egypt.
Clin Oral Implants Res. 2020 Feb;31(2):162-172. doi: 10.1111/clr.13552. Epub 2019 Nov 8.
The aim of this crossover study was to compare clinical denture base deformation with different attachments used for mandibular implant overdentures.
Twenty-four patients with edentulous mandibular ridges received two implants in the former canine regions. Three months thereafter, each patient was randomly given the following implant overdentures in a crossover design: (a) bar implant overdentures (BOD), (b) resilient telescopic implant overdentures (TOD), and (c) stud implant overdentures (SOD). Six linear strain gauges were attached to the lingual surface of the implant overdentures opposite to the abutments (Ch1and Ch2 at clenching [left] side and Ch5and Ch6 at non-clenching [right] side) and at midline (Ch3 and Ch4). Three months after wearing each implant overdenture, strain registrations were performed during clenching without food and during clenching on soft (cake) and hard (carrot) foods. Kruskal-Wallis test was used to compare denture strains between group, channels, and clenching conditions.
Bar implant overdentures showed significantly higher (p < .001) total microstrains (403.7 ± 306.8 μɛ) than TOD (146.9 ± 131.8 μɛ) and SOD (99.8 ± 75.6 μɛ). No difference in microstrain was noted between TOD and SOD (p = .06, n.s.). Channels opposite to the abutments at clenching side (ch2) recorded the highest total strain during clenching hard (390.4 ± 381.6 μɛ) and soft (223.5 ± 220.2 μɛ) foods. Clenching hard food was associated with significant higher total microstrain than clenching soft food (p = .002).
Telescopic and stud attachments are recommended to be used for two-implant mandibular over dentures as they were associated with reduced denture base deformation compared with bar attachments.
本交叉研究的目的是比较不同附着体用于下颌种植覆盖义齿时的临床义齿基托变形。
24 名无牙颌下颌牙槽嵴患者在前犬牙区植入 2 枚种植体。3 个月后，每位患者以交叉设计的方式随机接受以下种植覆盖义齿：（a）杆式种植覆盖义齿（BOD）、（b）弹性伸缩式种植覆盖义齿（TOD）和（c）球帽式种植覆盖义齿（SOD）。将 6 个线性应变计粘贴到与基台相对的义齿舌侧（咬合侧左侧的 Ch1 和 Ch2，非咬合侧右侧的 Ch5 和 Ch6，以及中线的 Ch3 和 Ch4）。佩戴每种种植覆盖义齿 3 个月后，在不进食时进行咬合和咀嚼软（蛋糕）、硬（胡萝卜）食物时进行应变记录。采用 Kruskal-Wallis 检验比较组间、通道间和咬合条件下义齿的应变。
杆式种植覆盖义齿的总微应变（403.7±306.8μɛ）明显高于伸缩式（146.9±131.8μɛ）和球帽式（99.8±75.6μɛ）（p<0.001）。伸缩式和球帽式之间的微应变无差异（p=0.06，n.s.）。咬合侧相对基台的 ch2 在咬合硬（390.4±381.6μɛ）和软（223.5±220.2μɛ）食物时记录到的总应变最高。咬合硬食物时的总微应变明显高于咬合软食物（p=0.002）。
与杆式附着体相比，伸缩式和球帽式附着体用于下颌双种植覆盖义齿可减少义齿基托变形，因此推荐使用。
