Optical impression method to measure three-dimensional position and orientation of dental implants using an optical tracker.
OBJECTIVE
The aim of this study was to devise an optical impression method that could make impressions of dental implants accurately and rapidly.


METHODS
Four paper markers (4 × 3 mm, 8 × 6 mm, 16 × 12 mm, and 24 × 18 mm) and one titanium marker (8 × 6 mm) were prepared to determine the measuring accuracy of the three-dimensional optical tracker. For a proposed and conventional impression taking method, we compared the reproduction accuracies of the positions and orientations of dental implants and the times to obtain impressions. Finally, we fabricated computer-aided designing (CAD)/computer-aided manufacturing (CAM) superstructure frameworks to determine the adaptation accuracy.


RESULTS
The 8 × 6-mm titanium marker was optimal among the prepared markers. Dental implants made by the proposed and conventional impression taking methods had measurement errors of 71 ± 31 μm and 32 ± 18 μm, respectively. The proposed method took a significantly shorter time to obtain an impression than did the conventional method. The connection between the CAD/CAM superstructure frameworks and four implant analogs had uplifts of 55 ± 10 μm, 94 ± 35 μm, 2 ± 1 μm, and 66 ± 3 μm.


CONCLUSIONS
Our proposed method and fabricated titanium markers enabled us to measure the positions and orientations of dental implants both accurately and rapidly. We then used the reproducible measurement results for the positions and orientations of the dental implants to fabricate CAD/CAM superstructure frameworks within an acceptable accuracy range.
Department of Fixed Prosthodontics, Osaka University Graduate School of Dentistry, Suita, Osaka, Japan.
Shinji
S
Ono
Satoshi
S
Yamaguchi
Naoki
N
Kusumoto
Tamaki
T
Nakano
Taiji
T
Sohmura
Hirofumi
H
Yatani
D000465:Algorithms; D017076:Computer-Aided Design; D015921:Dental Implants; D003761:Dental Impression Technique; D017267:Dental Prosthesis Design / Q000295:instrumentation*; D006801:Humans; D021621:Imaging, Three-Dimensional; D061848:Optical Imaging; D015203:Reproducibility of Results; D013997:Time Factors; D014025:Titanium
D015921:Dental Implants; D014025:Titanium