Acrylic Customized X-Ray Positioning Stent for Prospective Bone Level Analysis in Long-Term Clinical Implant Studies

Objectives: This paper describes a technique to produce individualized X-ray positioning devices for intraoral digital imaging of dental implants with long-term stability. Materials and Methods: An X-ray positioning device was built for Gendex Visualix eHD sensor, using the Dentsply rinn XCP-DS system individualized by the incorporation of the bite piece within an acrylic stent to perform successive standardized radiographs to 16 patients. X-ray tube stabilization was achieved with polivinylsiloxane. Series of 3 radiographs were taken to each patient in different moments. Specific linear measurements as the implant diameter (mesio-distal width) and the height between consecutive threads (thread pitch) were made to all radiographs to determine the reproducibility and accuracy of the procedure. Results: The intraclass correlation coefficient for the mesio-distal width was 0.964 [(0.920 0.986) 95% CI] (p < 0.01) and 0.990 [(0.976 0.996) 95% CI] (p < 0.01) for the thread pitch. Bland-Altman plots comparing implant diameter showed mean bias of 0.01 ± 0.01975, 0.01 ± 0.02243 and 0.0006 ± 0.025 for groups 1 2, 1 3 and 2 3 respectively. Mean bias of 0.0024 ± 0.00552, 0.0027 ± 0.00552 and 0.0003 ± 0.0012 was found for the thread pitch analysis of groups 1 2, 1 3 and 2 3. One sample t-test for trueness of mesio-distal width, thread pitch and ratio showed mean difference of 0.00156 mm for the test value of 3.3 (p = 0.9), −0.00026 mm for 0.8 (p = 0.96) and 0.0124 for 4.125 (p = 0.72), respectively, after the application of a magnification correction factor. Conclusion: The device produced reproducible images in different moments and was suitable for comparative clinical examinations of marginal bone as it was convenient to perform reliable linear measurements.