New implant prognosis model shows strong predictive value

Dental Tribune International

Fri. 10 April 2026

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SAN FRANCISCO, US: Unlike earlier implant prognosis models that focused on peri-implant bone loss or disease stage, a newly proposed system integrates multiple local and systemic determinants, extending periodontal prognosis frameworks to implants. A new retrospective study has conducted a validation of the system in a clinical setting. Its results have shown that this structured, risk-based prognosis system can reliably predict medium-term outcomes.

The new implant prognosis system takes into account plaque control, implant position, restoration design, history of periodontitis, supportive care, smoking, diabetes, osteoporosis, and additional modifiers such as antiresorptive medicines, radiotherapy, occlusion and possible genetic influences. The system classifies implants into four prognosis categories: favourable, questionable, unfavourable and hopeless.

The retrospective analysis assessed 651 implants in 291 patients with reference to the new implant prognosis system, proposed by Kwok et al., and validated its predictive capacity, demonstrating clear stratification of survival outcomes over a five-year period. Implants classified as having a favourable prognosis at baseline showed 100% survival, compared with 93.5% in the questionable group and just 33.3% in the unfavourable category. Additionally, the baseline prognosis remained unchanged over time for 95.7% of the implants in the favourable category, 78.5% in the questionable category and 33.3% in the unfavourable category. Together, these results underline the model’s ability to differentiate clinical risk.

The study also identified anatomical variation in the system’s prognostic reliability, showing that implant outcome was predicted more consistently for mandibular implants, a finding that the authors said likely reflected differences in bone quality. In the mandible, anterior and premolar sites were more reliably assessed than molar sites, whereas in the maxilla, prognosis was consistently predictive only for central incisors.

Based on this, the authors argue that the Kwok et al. system is useful but may be incomplete. They suggest that future versions could also consider implant phenotype, more detailed prosthetic factors, implant location in the mandible versus maxilla, and possibly use of antidepressants, since these may affect implant survival and thus the accuracy of prognosis. Overall, they present the system as an evolving framework that will likely need refinement as more evidence becomes available.

Overall, the findings support the use of structured prognosis frameworks in implant dentistry. By assessing prognosis through a broader combination of local and systemic determinants, clinicians may be better positioned to plan treatment, identify high-risk patients earlier and better communicate likely outcomes.

The article, titled “Predictability of a dental implant prognosis system: A retrospective study”, was published online on 6 March 2026 in the Journal of Periodontology, ahead of inclusion in an issue.