Stress Distribution Analysis of Threaded Implants for Digital Dentistry

Accuracy of implant height and width measurement with triaxial rotation method based on cone-beam CT

Objective

To investigate the accuracy of implant height and width measurement in the mandibular and maxillary first molar region based on cone-beam CT (CBCT) data, and to establish an accurate method for bone measurement in the implant region.

Materials and methods

CBCT images of 122 patients with implant in mandibular or maxillary first molar region were retrospectively collected. Two methods were used to measure sagittal height (SH), coronal height (CH), sagittal width (SW), and coronal width (CW) of implants. Method 1 (general method): the images were analyzed using the built-in software NNT 9.0 software. SHl, CHl, SWl, and CWl were measured on the reconstructed sagittal and coronal based on the radiologist's own experience. Method 2 (triaxial rotation method): the raw data were demonstrated in Expert mode of NNT 9.0 software, in which the coronal axis and sagittal axis were rotated paralleling to the long axis of the implant for reconstruction, and then SH2, CH2, SW2, and CW2 were measured on the reconstructed sagittal and coronal images. The results of two methods were compared with the actual implant size (H0, W0). Paired T-test was performed for statistical analysis. Dahlberg formula was used to check the measurement error.

Results

For method 1, there was no significant differences between SHl and H0 (P > 0.05), but significant differences between CHl and H0, SWl and W0, and CWl and W0 (P < 0.05). For method 2, there were no significant differences between all measurements and actual size (P > 0.05). The random error range measured using Dahlberg formula was 0.157-1.171 mm for general method and 0.017-0.05 mm for triaxial rotation method.

Conclusion

The triaxial rotation method is accurate for implant height and width measurements on CBCT images and could be used in pre-operatively bone height and width measurement of potential implant sites.

Impact of Vitamin D on Osseointegration in Dental Implants: A Systematic Review of Human Studies

This systematic review evaluates the impact of Vitamin D levels on dental implant osseointegration, hypothesizing that optimal Vitamin D enhances success rates, and aims to synthesize data on its relationship with clinical outcomes in implantology. A comprehensive search across PubMed, Cochrane Library, and Web of Science databases included seven peer-reviewed articles meeting the criteria for the review. These studies, conducted between 2008 and 2021, included human subjects and explicitly correlated serum Vitamin D levels with dental implant outcomes, following PRISMA guidelines. The selected studies involved 1462 participants and examined 4450 dental implants. Key findings included a varied implant loss rate ranging from 3.9% to 11.4% across the studies. One study reported a 9.8% implant loss rate, yet found no significant association between Vitamin D receptor polymorphism and implant success. Another study indicated successful implantation following Vitamin D3 supplementation, even in severe deficiency cases. The highest implant loss rate (11.1%) was observed in severely Vitamin D-deficient patients, particularly when compounded by risk factors such as smoking and periodontal disease. Additionally, one study noted significantly improved bone density following post-surgical Vitamin D supplementation for up to 12 weeks. The review supports a link between sufficient Vitamin D levels and successful dental implant osseointegration, suggesting Vitamin D deficiency as a potential risk factor for increased failure and advocating for Vitamin D evaluations in pre-surgical planning to potentially enhance implantology outcomes.