Accuracy of Guided Implant Surgery Using Desktop 3-D Printed Guides

Objectives: 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.
Methods: Fifteen implants were virtually planned to replace a missing first mandibular molar, using planning software for guided implant surgery (Exoplan®, Exocad GmbH, Darmstadt, Germany). A tooth supported guide was designed and manufactured using a desktop 3D printer (D40, Rapidshape GmbH, Heimsheim, Germany). The implants were placed fully guided in the casts and a digital impression was taken to register their position in the cast. This scan was compared with the virtual position in the implant planning software, using metrology software (Geomagic Qualify X, Geomagic Research Triangle Park, NC, USA).
Results: The mean angular deviation was 2.63° (SD 1.69°; range 0.38° - 5.99°), the mean coronal deviation, 0.52 mm (SD 0.25; range 0.09 mm – 1.07 mm) and the mean apical deviation 0.90 mm (SD 0.47; range 0.14 mm – 1.74 mm). The absolute apical mean deviation in bucco-lingual direction (x-axis) was 0.70mm (SD 0.42, 0.12 mm – 1.65 mm) (p<0.001), in the mesio-distal direction (y-axis) 0.34mm (SD 0.26; range 0.01 mm – 0.80 mm) (0.650) and in the vertical direction (z-axis) 0.32mm (SD 0.27; range 0.02 mm - 1.00 mm) (p=0.010).
Conclusions: Based on this in vitro study, an in-house planning followed by a desktop 3-D printing of a tooth-supported guide yields an acceptable accuracy for single implant placement which opens possibility for future clinical implementation. Further investigations are required to confirm this in a clinical setting.