Pedroche Lorena Oliveira, Bernardes Sérgio Rocha, Leão Moira Pedroso, Kintopp Cibele Cândida de Almeida, Correr Gisele Maria, Ornaghi Bárbara Pick, Gonzaga Carla Castiglia
Universidade Positivo, Graduate Program in Dentistry, Curitiba, PR, Brazil.
Instituto Latino Americano de Pesquisa e Ensino - ILAPEO, Curitiba, PR, Brazil.
Braz Oral Res. 2016 Oct 10;30(1):e113. doi: 10.1590/1807-3107BOR-2016.vol30.0113.
The objective of this study was to evaluate the marginal and internal fit of zirconia copings obtained with different digital scanning methods. A human mandibular first molar was set in a typodont with its adjacent and antagonist teeth and prepared for an all-ceramic crown. Digital impressions were made using an intraoral scanner (3Shape). Polyvinyl siloxane impressions and Type IV gypsum models were also obtained and scanned with a benchtop laboratory scanner (3Shape D700). Ten zirconia copings were fabricated for each group using CAD-CAM technology. The marginal and internal fit of the zirconia copings was assessed by the silicone replica technique. Four sections of each replica were obtained, and each section was evaluated at four points: marginal gap (MG), axial wall (AW), axio-occlusal edge (AO) and centro-occlusal wall (CO), using an image analyzing software. The data were submitted to one-way ANOVA and Tukey's test (α = 0.05). They showed statistically significant differences for MG, AO and CO. Regarding MG, intraoral scanning showed lower gap values, whereas gypsum model scanning showed higher gap values. Regarding AO and CO, intraoral digital scanning showed lower gap values. Polyvinyl siloxane impression scanning and gypsum model scanning showed higher gap values and were statistically similar. It can be concluded that intraoral digital scanning provided a lower mean gap value, in comparison with conventional impressions and gypsum casts scanned with a standard benchtop laboratory scanner.
本研究的目的是评估采用不同数字扫描方法获得的氧化锆基底冠的边缘适合性和内部适合性。将一颗人类下颌第一磨牙连同其邻牙和对颌牙置于牙列模型中，并预备全瓷冠。使用口内扫描仪（3Shape）制取数字印模。还制取了聚醚橡胶印模和IV型石膏模型，并用台式实验室扫描仪（3Shape D700）进行扫描。每组使用CAD-CAM技术制作10个氧化锆基底冠。采用硅橡胶复制技术评估氧化锆基底冠的边缘适合性和内部适合性。每个复制件获取四个切片，每个切片在四个点进行评估：边缘间隙（MG）、轴壁（AW）、轴-咬合边缘（AO）和中央咬合壁（CO），使用图像分析软件。数据进行单因素方差分析和Tukey检验（α = 0.05）。结果显示，MG、AO和CO存在统计学显著差异。关于MG，口内扫描显示间隙值较低，而石膏模型扫描显示间隙值较高。关于AO和CO，口内数字扫描显示间隙值较低。聚醚橡胶印模扫描和石膏模型扫描显示间隙值较高，且在统计学上相似。可以得出结论，与用标准台式实验室扫描仪扫描的传统印模和石膏模型相比，口内数字扫描提供的平均间隙值更低。
