Accuracy of Guided Implant Surgery Using an Intraoral Scanner and Desktop 3D-Printed Tooth-Supported Guides

The increasing popularity of desktop 3D printers makes guided surgery more accessible. The aim of this in vitro study was to evaluate the accuracy of single-tooth guided implant surgery by means of a 3D-printed tooth-supported guide.

Fifteen implants were virtually planned to replace a missing first mandibular molar, using planning software for guided implant surgery (Exoplan, Exocad). A tooth-supported guide was designed and manufactured using a desktop 3D printer (Asiga MAX UV). The implants were placed fully guided in resin casts, and a digital impression was taken to register their position. This scan was compared with the virtual implant position in the planning software, and the internal fit of the guides was evaluated using metrology software. One planning was executed six times for measuring precision.

For trueness, the mean angular deviation was 2.63 degrees (SD: 1.69 degrees; range: 0.38 to 5.99 degrees), the mean coronal deviation was 0.52 mm (SD: 0.25; range: 0.09 mm to 1.07 mm), and the mean apical deviation was 0.90 mm (SD: 0.47; range: 0.14 to 1.74 mm). The absolute apical mean deviation in the buccolingual direction (x-axis) was 0.70 mm (SD: 0.42, 0.12 to 1.65 mm; P < .001); in the mesiodistal direction (y-axis), it was 0.34 mm (SD: 0.26; range: 0.01 to 0.80 mm; P = .650); and in the vertical direction (z-axis), it was 0.32 mm (SD: 0.27; range: 0.02 to 1.00 mm; P = .010). The mean internal fit of the guides was 79.5 μm (SD: 19.6 μm; range: 51 to 118 μm).

Desktop 3D-printed tooth-supported guides demonstrate an acceptable fit and acceptable level of accuracy for single implant placement.