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Aim: To assess, in vitro, variables potentially influencing implant blooming using a human‐like imaging phantom and 3D‐printed mandibles. Material and Methods: Sixty implants were inserted in 3D‐printed mandibles in 26 different configurations in order to examine the impact of implant diameter, presence of a cover screw, implant design/material, implant position, and the presence of additional implants on implant blooming using two cone‐beam computed tomography (CBCT) devices (Accuitomo [ACC] and NewTom [NWT]). Two observers measured the amount of implant blooming in both buccolingual and mesiodistal directions. Inter‐rater agreement and descriptive statistics, grouped by implant characteristic and CBCT device, were calculated. Results: Both CBCT devices increased implant diameter (a mean increase of 9.2% and 11.8% for titanium, 20.3% and 24.4% for zirconium, for ACC and NWT, respectively). An increase in implant diameter did not increase the amount of blooming, whereas placing a cover screw did (from 8.0% to 10.9% for ACC, and from 10.0% to 15.6% for NWT). Moreover, implant design, anatomical region, and the presence of another implant also affected the extent of the blooming. Conclusions: Dental implants show a clear diameter increase on CBCT, with the effect being more pronounced for zirconium than for titanium implants. Similar effects are likely to occur in the clinical setting, potentially masking nonosseointegration, reducing the dimensions of peri‐implant defects, and/or causing underestimation of the buccal bone thickness. [ABSTRACT FROM AUTHOR]

Objectives: To measure in vivo 3D accuracy of backward‐planned partially guided implant surgery (PGIS) based on dental magnetic resonance imaging (dMRI). Material and Methods: Thirty‐four patients underwent dMRI examinations. Tooth‐supported templates were backward planned using standard dental software, 3D‐printed, and placed intraorally during a cone beam computed tomography (CBCT) scan. Treatment plans were verified for surgical viability in CBCT, and implants were placed with guiding of the pilot drill. High‐precision impressions were taken after healing. The 3D accuracy of 41 implants was evaluated by comparing the virtually planned and definitive implant positions with respect to implant entry point, apex, and axis. Deviations from the dMRI‐based implant plans were compared with the maximum deviations calculated for a typical single implant. Results: Twenty‐eight implants were placed as planned in dMRI. Evaluation of 3D accuracy revealed mean deviations (99% confidence intervals) of 1.7 ± 0.9mm (1.2–2.1mm) / 2.3 ± 1.1mm (1.8–2.9 mm) / 7.1 ± 4.8° (4.6–9.6°) for entry point / apex / axis. The maximum deviations calculated for the typical single implant surpassed the upper bounds of the 99% CIs for the apex and axis, but not for the entry point. In the 13 other implants, dMRI‐based implant plans were optimized after CBCT. Here, deviations between the initial dMRI plan and definitive implant position were only in part higher than in the unaltered group (1.9 ± 1.7 mm [0.5–3.4 mm] / 2.5 ± 1.5 mm [1.2–3.8 mm] / 6.8 ± 3.8° [3.6–10.1°] for entry point / apex / axis). Conclusions: The 3D accuracy of dMRI‐based PGIS was lower than that previously reported for CBCT‐based PGIS. Nonetheless, the values seem promising to facilitate backward planning without ionizing radiation. [ABSTRACT FROM AUTHOR]