Exploring Effectiveness of Computer-Aided Planning in Implant Positioning for a Single Immediate Implant Placement
The value of computer-aided implant planning using cone-beam computerized tomography (CBCT) for single immediate implants was explored. Eighteen patients requiring extraction of a tooth followed by a single immediate implant were enrolled. Small volume preoperative CBCT scans were used to plan the position of the implant. A taper screwed–type implant was immediately placed into a fresh socket using only the final 1 or 2 drills for osteotomy. Postoperative CBCTs were used for the analysis of actual implant placement positioning. Measurements of the planned and the actual implant position were made with respect to their position relative to the adjacent teeth. Mesio-distal displacements and the facial-lingual deviation of the implant from the planned position were determined. Changes in the angulation of the planned and actual implant position in relation to the clinical crown were also measured. To statistically summarize the results, box plots and 95% CIs for means of paired differences were used. The analysis showed no statistical difference between the planned position and final implant placement position in any measurement. The CBCT scans coupled with the computer-aided implant planning program along with a final 1-to-2 drill protocol may improve the accuracy of single immediate implant placement for taper screwed–type implants.

Clinical treatment sequences. (a) Preoperative occlusal view and (b) preoperative buccal view. (c) The tooth was extracted with minimal trauma using periotomes and small straight elevators to limit the damage to the facial alveolar bone. (d) The socket was thoroughly curetted to remove remaining periapical granulation tissue and was irrigated with 0.12% chlorhexidine and normal saline solution. (e) The osteotomy was made using only the final 1 or 2 drills recommended by the manufacturer. In cases with thick palatal bone (>2 mm), a bone tap was used to create threads for the implant fixture, thus allowing a more accurate position.1 (f) The position of the implant fixture insertion device, Fixture Mount (Zimmer Dental) was used to determine the implant mesio-distal and facio-lingual positions, as well as the implant angulation compared with the planned implant position in silico. (g) A root-form endosseous implant (Tapered-Screw vent [TSV], Zimmer Dental) was placed. (h) The fixture placed lingual to the buccal alveolar plate and (i) prefabricated provisional abutment. (j) A screw-retained provisional crown fabricated from provisional abutment (Zimmer Dental) and bis-acryl acrylic resin (Integrity, Dentsply) was made and installed. (k) Occlusal view of provisional crown in place. The provisional crown had no occlusal contacts in the maximum intercuspal position or in lateral excursive movements. (l) Buccal view of provisional crown in place.

Preoperative planning and measurements. (a) Sagittal view showing facio-lingual dimension of planned implant superimposing on the to-be-extracted tooth and the angle between planned implant and clinical crown. (b) Occlusal view of planned implant showing measurement from planned implant to lingual plane of the adjacent teeth. (c) Panoramic view of planned implant showing the mesio-distal measurements. (d) 3D view of planned implant.

Postoperative measurements. (a) Sagittal view showing facio-lingual dimension of actual implant and the angulation between the clinical crown and the implant fixture. (b) Occlusal view of actual implant showing measurement from implant to lingual plane of the adjacent teeth. (c) Panoramic view of actual implant showing the mesio-distal measurements. (d) 3D view of actual implant.

Box plots of paired differences in final placement and planned positions for the 3 distance measures and box plot of paired difference in the angle between final and planned implant and clinical crown. The shaded box shows the range of half of the data based on the interquartile range (IQR; ie, difference between lower and upper quartiles, or 25th and 75th percentiles, respectively). The bars at the end of the extended lines show, respectively, the maximum (minimum) value lesser (greater) than or equal to the mark (not shown) that is 1.5 IQRs above (below) the upper (lower) quartile. Means are shown as diamonds, and outliers are shown as circles. *All measurements are in millimeters except IT is in degrees. DI indicates distal tooth to the implant fixture; IT, angulation between the clinical crown and the implant fixture; LI, implant to the lingual plan; MI, mesial tooth to the implant fixture.
Contributor Notes