A new navigation system for dental implantology

G. Pellegrino1, V. Taraschi2, C. Marchetti1

1University of Bologna, Bologna, Italy2University of Sydney, Sydney, NSW, Australia

Background

The use of Computer-Aided Systems (CAS) for implant placement is the new trend of the last years. A pre-operative virtual planning in conjunction with a surgical guide could help the surgeon with a prosthetic correct implant placement, especially in difficult clinical cases. The most used systems are surgical drill guides which present some clinical limits such as costs and preparation time. Moreover, the accuracy of this system, as reported in literature, could not guarantee enough safety in the treatment of atrophic jaws. The use of navigation systems, as already used in major surgery (neurosurgery, orthopedics, etc. etc.), may solve some of these problems and widen the routine use of computer aided surgery in dental implantology. Our research is finalized to simplify the procedures and the tools for a simplified use of navigation systems in implant surgery with an acceptable clinical accuracy. A new software to use a navigation system has been created and innovative tools to be used in conjunction with it were designed and manufactured.

Aim/Hypothesis

the objective of our project is to evaluate the accuracy of a new set of a specific software and tools (ImplaNav, BresMedical, Ingleburn, Australia) realized to perform image guided surgery in dental implantology. In vitro tests have been carried out in order to evaluate the accuracy of this new system and also preliminary clinical results have been presented.

Material & Methods

Clinical procedures were simulated on five laser-sintered (PA2200) mandible models. A pre-operative Cone Beam CT scan of the models was taken with the fiducial markers mounted on a specific tool. Four implants for each model were virtually placed using the ImplaNav software. After the calibration of the surgical instrument is completed according to the protocol the drilling procedure and therefore the implant placement (Hex-Ex, Southern Implant, Irene, South Africa) under the navigator system’s guide was performed. A post-operative scan of the models was performed and the implants were segmented from the volume so as to evaluate and measure the deviation from the planned position via a numerical analysis. The deviation resulted comparable to that reported in literature for similar systems therefore a clinical protocol was submitted to ethical committee. A pilot clinical study was performed to test the clinical feasibility of the whole procedure. The clinical trial is still in progress.

Results

The in vitro study shows an average deviation of about 0.9 ± 0.8 mm; the preliminary clinical results are encouraging and under evaluation.

Conclusion & Clinical implications

Navigation systems could become of routine use just as surgical drill guides and with an acceptable accuracy. Some advantages of these systems make them useful in specific clinical cases such as implant placement in sites of bone regeneration or limited interocclusal distance for drill guide. A dedicated software and tools for dental implantology are needed to make navigation systems easy to use clinically. The technological development of the interactive and video devices up to augmented reality could increase exponentially the employment of these systems.