Comparison of post-operative intraoral scan versus cone beam computerised tomography to measure accuracy of guided implant placement- a prospective clinical study.

Objective To evaluate the accuracy of implant placement with a digitally planned guided implant procedure. Two methods for identifying the actual postoperative positioning of the implants were compared: CBCT and IO scanning. Material and methods Twenty-eight implants with a sandblasted and acid-etched surface were placed in thirteen patients using tooth-supported surgical guides following a digital planning procedure. The implants were submerged for 12-15 weeks. New CBCT images were taken for identification of the implant position. After second stage surgery, scan bodies were mounted on the implants and scanned with an IO digital scanner. The recordings from the CBCT images and the IO scans were compared with respect to the identified positions of the implants. Results The study did not resolve any significant differences of the identified positioning of the implants as measured by CBCT or IO, except for the apical deviations at the coronal and apical points. The angular difference between CBCT and IO scanning at the coronal point was -0.011 (+/- 0.6) degrees, whereas the 3D deviation was 0.03(+/- 0.17) mm. The distal deviation between CBCT and IO scanning was 0.01(+/- 0.16) mm, and the vestibular deviation 0.033(+/- 0.16) mm and the apical deviation difference was 0.09(+/- 0.16) mm. The 3D deviation at the apical point was 0.04(+/- 0.22) mm. The distal deviation between CBCT and IO scanning was 0.06(+/- 0.19) mm, and the vestibular deviation 0.032(+/- 0.23) mm and the apical deviation difference was 0.09(+/- 0. 16) mm. Conclusion The study demonstrated that accuracy measurements using IO scanning yields comparable results to those obtained by CBCT.