Aim: The aim of this study was to place virtual mini-implants (MIs) in implant planning software and determine bone thickness (BT) as well as MI proximity to the root at various angulations.
Materials and methods: A total of 55 cone-beam computed tomographies (CBCTs) were superimposed with the intraoral scans of the respective patients in the virtual implant planning software (3Shape Unite). The BT and root proximity of the virtual MIs were measured at 40°, 50°, and 70° to the tooth's long axis. IBM SPSS Statistics Software was used for the statistical analysis. Kruskal–Wallis test was used for intergroup and intragroup comparisons. Mann–Whitney U test was used for comparison among gender.
Results: The BT was 1.27 ± 0.3, 1.06 ± 0.3, and 1.03 ± 0.21 at 40°, 50°, and 70° angulations, respectively (p < 0.05). The root proximity of virtual implants was 1.9 ± 1.01, 1.6 ± 0.8, and 0.5 ± 0.2 at 40°, 50°, and 70° angulations (p < 0.05). No significant differences were found among males and females at 40°, 50°, and 70° angulation for BT. However, the distance from the root at 50° was significantly lesser for females as compared to males (p < 0.05). Intragroup comparisons showed statistical significance for BT among all groups (p < 0.05), for root proximity of the virtual implants among groups I and III (p < 0.05).
Conclusion: The mean cortical BT decreased, and the root proximity of virtual implant increased as the placement angulation increased from 40° to 70°. The BT did not differ significantly among males and females at all the angulations. The distance between the root and virtual implants was significantly lesser for females than males, only at 50° angulation.
Clinical significance: Using virtual MI software will help in the accurate placement of MIs by engaging the maximum thickness of bone and reducing the failure rates by preventing root contact.
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