Accuracy Evaluation of the Computer-Designed Selective Laser Sintering Surgical Guide for Flapless Immediate Loading Dental Implants Surgery in Edentulous Jaws
This study was designed to evaluate the accuracy of a novel computer-designed and selectively laser sintered surgical guide for flapless dental implant placement in the edentulous jaw. Fifty dental implants were placed in 11 patients with at least 1 totally edentulous jaw. Initially, cone-beam computed tomography (CBCT) was performed in each patient to define the virtual position of the dental implants based on the assessment of bone availability and the proposed dental prosthesis. After virtual planning, 3D surgical guides were printed using selective laser sintering. CBCT was repeated after the surgery, and the pre- and postoperative images were overlapped in computer-assisted design software to compare the planned and actual positions of the dental implants using a 1-sample t test. The mean ± angular standard deviation between the long axes of the planned and final dental implant positions was 4.58° ± 2.85°; the linear deviation in the coronal position was 0.87 ± 0.49 mm and in the apical region of the dental implants was 1.37 ± 0.69 mm. These differences were statistically significant (P < .001). The proposed modifications reduced the deviations, resulting in an improvement in the technique. We were able to place implants and temporary prostheses using the present protocol, taking into account the differences between the planned and final positions of the dental implants.

Virtual planning. Occlusal extensions of dental implants (green vertical cylinders) and 3 fixation pins (green horizontal cylinders) to fix the denture (yellow) to the mandible (white).

Figure 2. Intraoperative surgical guide with 3 fixation pins and 4 guide tubes.
Figure 3. Conical and cylindrical abutments placed.

The temporary fixed prosthesis is placed over the alveolar ridge mucosa and attached to the metal cylinders with acrylic resin.

3D evaluation of the virtually planned and postoperative dental implant positions.

Comparison of the deviation of the final dental implant positions from the planned positions in the apical and coronal regions (mm) according to the categorization as clinically negligible (≤1.0 mm), probably clinically irrelevant (>1.0 mm, ≤2.0 mm), or potentially clinically relevant (>2.0 mm).
Contributor Notes