Sarath Chandra Govindaraj, Jagdish Sivanesan Karthikeyan, Murugesan Krishnan, Muthukumar Balasubramaniam
Department of Prosthodontics, Rajas Dental College and Hospital, Thirunelveli, Tamil Nadu, India.
Department of Prosthodontics, Chettinad Dental College and Research Institute, Kelambakkam, Tamil Nadu, India.
Contemp Clin Dent. 2018 Sep;9(Suppl 2):S283-S290. doi: 10.4103/ccd.ccd_280_18.
There has been less focus on methods to improve the clinical performance of partial veneer crowns. In this study, we wanted to explore the potential of two new surface treatment modalities (laser etching and spark erosion) for improving the longevity of partial veneer crowns.
Conventional partial veneer crown preparation was done on 90 extracted premolars by a single operator. All the samples used in the study were divided into three groups. Group A were samples to be treated by sandblasting alone, Group B were samples to be treated by sandblasting followed by laser etching, and Group C were samples to be treated by sandblasting followed by spark erosion. Each group consisted of two Sub Groups: Sub Group I-Retention test group, Sub Group: II-Resistance test group. The prepared teeth were randomly allotted to the three groups and subgroups using lot method. Partial veneer crown copings were fabricated for testing retention and resistance. Castings in each subgroup were luted with resin cement to their respective tooth preparations. Retention and resistance testing of samples were done with the use of an Instron Universal testing machine.
The two surface treatments, laser etching and spark erosion (Groups B and C) of metal copings significantly improved the retention and resistance compared to sandblasted surfaces alone ( ≤ 0.05). Retention and resistance of copings which were sandblasted and spark eroded (Group C) were found to be highest among the three groups ( ≤ 0.05).
Within the limitation of this study, it can be concluded that the combination of spark erosion and sandblasting significantly improves the retention and resistance values of partial veneer crown. This study helps to provide better knowledge about the surface treatment required for success of partial veneer crowns.
以往较少关注改善部分贴面冠临床性能的方法。在本研究中,我们想探索两种新的表面处理方式(激光蚀刻和电火花加工)对提高部分贴面冠使用寿命的潜力。
由一名操作人员对90颗拔除的前磨牙进行常规部分贴面冠预备。研究中使用的所有样本分为三组。A组为仅进行喷砂处理的样本,B组为喷砂后进行激光蚀刻处理的样本,C组为喷砂后进行电火花加工处理的样本。每组又分为两个亚组:亚组I - 固位测试组,亚组II - 抗力测试组。使用抽签法将预备好的牙齿随机分配到三组及亚组中。制作部分贴面冠内冠用于测试固位力和抗力。每个亚组的铸件用树脂粘结剂粘结到各自的牙齿预备体上。使用英斯特朗万能试验机对样本进行固位力和抗力测试。
与仅进行喷砂处理的表面相比,对金属内冠进行激光蚀刻和电火花加工这两种表面处理(B组和C组)显著提高了固位力和抗力(P≤0.05)。在三组中,喷砂并经过电火花加工处理的内冠(C组)的固位力和抗力最高(P≤0.05)。
在本研究的局限性范围内,可以得出结论,电火花加工与喷砂相结合能显著提高部分贴面冠的固位力和抗力值。本研究有助于更好地了解部分贴面冠成功所需的表面处理知识。