Almaslamani Faiez S, Al-Subaie Rakan M, Al-Rafee Mohammed A, Rayyan Mohammad R
Int J Comput Dent. 2023 Feb 24;26(1):31-36. doi: 10.3290/j.ijcd.b3818295.
The present study aimed to investigate the effect of pulp chamber depth on the failure load and mode of failure of CAD/CAM endocrowns.
Thirty mandibular molars were sectioned above the cementoenamel junction (CEJ), followed by root canal treatment. Teeth were sectioned at a level of 1.5 mm above the CEJ, arranged from the lowest to the highest depths, and divided into three groups (n = 10): group SE: Shallow pulp chamber (1.42 to 2.17 mm); group IE: Intermediate pulp chamber (2.25 to 3.17 mm); group DE: Deep pulp chamber (3.33 to 5.17 mm). CAD/CAM endocrowns were fabricated by milling lithium disilicate ceramic blocks and were cemented using resin cement. Teeth were embedded in acrylic resin at 2 mm below the CEJ, and a compressive load was applied to create a 45-degree angled functional loading simulation until the occurrence of failure.
The mean failure loads were highest in group DE (1893.75 ± 496.08 N) compared with groups IE (1103.71 ± 254.59 N) and SE (1084.63 ± 240.92 N), with statistically significant differences between group DE and both groups IE and SE (P < 0.001). Pearson correlation coefficient (PCC) revealed a strong positive correlation between the pulp chamber depth and failure load of the endocrowns. The failure mode for all samples was catastrophic failure.
The pulp chamber depth affected the failure load of the teeth restored with endocrowns. The failure loads were higher in teeth with a greater pulp chamber depth. (Int J Comput Dent 2023;26(1): 31-0; doi: 10.3290/j.ijcd.b3818295).
本研究旨在探讨髓腔深度对计算机辅助设计/计算机辅助制造(CAD/CAM)嵌体冠的破坏载荷及破坏模式的影响。
30颗下颌磨牙在牙骨质釉质界(CEJ)上方进行切割,随后进行根管治疗。在CEJ上方1.5mm处对牙齿进行切割,按髓腔深度从低到高排列,分为三组(n = 10):SE组:浅髓腔(1.42至2.17mm);IE组:中髓腔(2.25至3.17mm);DE组:深髓腔(3.33至5.17mm)。通过铣削二硅酸锂陶瓷块制作CAD/CAM嵌体冠,并用树脂水门汀粘结。将牙齿在CEJ下方2mm处嵌入丙烯酸树脂中,并施加压缩载荷以模拟45度角的功能载荷,直至发生破坏。
与IE组(1103.71±254.59N)和SE组(1084.63±240.92N)相比,DE组的平均破坏载荷最高(1893.75±496.08N),DE组与IE组和SE组之间均存在统计学显著差异(P < 0.001)。Pearson相关系数(PCC)显示髓腔深度与嵌体冠的破坏载荷之间存在强正相关。所有样本的破坏模式均为灾难性破坏。
髓腔深度影响了用嵌体冠修复牙齿的破坏载荷。髓腔深度较大的牙齿破坏载荷更高。(《国际计算机牙科杂志》2023年;26(1):31 - 0;doi:10.3290/j.ijcd.b3818295)