EAO Library

Virtual planning and subsequently guided implant placement with a surgical template allows for flapless surgery. However, rising a flap can often not be avoided due to insufficient bone volume and mucosal quality. The use of pilot drill templates combines the advantages of preoperative virtual implant planning and the possibility of additional surgical augmentative procedures with a conventional flap. However, little data is available comparing the time needed to perform these placement methods.To compare the duration of oral implant placement between free-hand (with flap), partially guided (with flap) and fully guided (flapless) surgical approaches. The null-hypothesis was that the distribution of time duration would be the same across the three methods.A controlled in-vitro study with 60 identical maxillary models (3D printed polylactic acid filament) missing the teeth 15 and 24 25 26 (FDI) was performed. Based on a cone beam tomography and a surface scan an ideal virtual implant planning was prepared for the three positions 15 (length diameter 13mm 4.3mm), 24 (13mm 4.3mm) and 26 (10mm 4.3mm). Twenty dentists viewed this specific planning and subsequently performed the placement of 3 implants per model and approach- A) free hand (no surgical template, with flap), B) pilot-drilling (NobelGuide tooth supported template, 2.0mm sleeve, with flap), C) fully-guided (NobelGuide tooth supported template, 4.3mm sleeve, flapless). Non-parametric methods were used for statistical comparison of the time duration between the approaches.The mean time duration for placement of the 3 implants (15, 24, 26) was significantly different between the three approaches (Kruskal-Wallis Test p<0.001) and ranged between 18-55min (A), 17-35min (B), and 7-17min (C). Mean values and 95% confidence intervals were 33min 28-38min for A (free-hand with flap), 24min 21-26min for B (pilot-drilling with flap), and 10min 9-12min for C (fully-guided without flap).In this controlled in-vitro study directly comparing identical implant sites, the duration for implant placement with a fully-guided flapless approach was significantly shorter than the partially guided approach (with flap) and the conventional free-hand approach with flap. If a fully-guided approach is indicated and reasonable, then surgical time and, thus, invasiveness, amount of perioperative anaesthetics, need for postoperative pain killers and morbidity can be reduced.