Abstract
Objective To investigate the dimensional discrepancy and degree of deviation of All-on-Four
implant position between different cone-beam computed tomography (CBCT) machines.
Materials and Methods Four implants (4.5 × 10 mm Superline II, Dentium, South Korea) were placed in an
All-on-Four style in an artificial mandible. The jaw was radiated 30 times using three
different CBCT machines (Rainbow CT, Dentium; Veraview X800, Morita, Japan; Planmeca
Viso G3, Planmeca OY, Finland). A total of 30 Digital Imaging and Communications in
Medicine (DICOM) files were exported, n = 10. All-on-Four implants from each DICOM file were segmented and exported as an
STL file (three-dimensional image) using Blue Sky Plan software (version 4.12.13/Blue
Sky Bio, United States). All-on-Four implant zone dimensions (X, Y, and Z axes) and the total degree of deviation between All-on-Four implants per CBCT machine
were measured using Autodesk Meshmixer software (version 3.5.474/California, United
States). The data distribution's normality and variances' equality were tested with
Shapiro–Wilk's and Levene's tests, respectively (p-value < 0.05). Data were analyzed using Brown–Forsythe one-way analysis of variance
and Tamhane's post hoc tests to compare the differences between the groups (p-value <0.05).
Results The respective X, Y, and Z mean dimensions of the All-on-Four implant zone were: Dentium (34.95, 14.71, and
9.97); Morita (34.88, 14.74, and 10.56); and Planmeca (34.73, 15.15, and 12.33). Significant
differences between CBCT machines were found in all axes (p-value < 0.05); however, the Z-axis had the most differences. Notably, Planmeca exhibited the highest standard deviation
(SD) in all axes (0.16–0.35), exhibiting the lowest consistency in the CBCT machines'
readings. The Dentium exhibited the lowest deviation in the implant position, with
the lowest SD (0.61). A significant difference in the total degree of deviation was
spotted when only Morita was included in the comparison (p-value < 0.05).
Conclusion This study's findings are of significant importance as they reveal that the implant
position recorded from the CBCT machines was most discrepant in the buccolingual dimension
(Z-axis). Planmeca exhibited the least implant-dimensional accuracy of the CBCT machines,
while Dentium exhibited the highest implant position accuracy. These results could
significantly impact the choice of CBCT machine for implant placement, especially
since an accurate CBCT image is crucial for digital implant planning.
Keywords
CBCT - All-on-Four - precision - degree of deviation
