Predictability of reformatted computed tomography for pre-operative planning of endosseous implants

Objectives: To determine the reliability of reformatted 2D-CT for pre-opera tive planning of implant placement. Methods: One hundred consecutive partially or fully edentate patients under went 2-D reformatted CT pre-operative planning and subsequent implant place ment. The number, site and size of the implants, the available bone height and anatomical complications were recorded. The pre-operative planning and the outcome at surgery were compared statistically using a percentage agree ment and Kendall's correlation coefficient. Results: Agreement between the pre- and Intra-operative data was good for t he number of implants (60%) and the selected sites (70%). From a total of 4 16 implants planned, 21 implants could not be placed because of intra-opera tive findings. Agreement was relatively poor for implant size (44%) and ana tomical complications (46%). Kendall's correlation coefficient was highest for the number of implants (0.80) and implant sites (0.81). It was much low er for implant sizes (0.51) and did not reach significance for anatomical c omplications (0.09). Conclusions: Reformatted 2D-CT is reliable for the pre-operative assessment of the number and sites of implants in the jaws. It is less predictable fo r the implant size needed and poor for anatomical complications.