Predictability of a dental implant prognosis system: A retrospective study

BACKGROUND: This study aimed to evaluate the predictability of the dental implant prognosis system proposed by Kwok et al. in 2023 by assessing implant survival rates across different initial prognosis categories over a 5-year period. METHODS: Data were retrospectively collected from patients who received at least one dental implant from 2013-2022 at a single university-affiliated dental center. Eligible participants received baseline examinations at the time of implant-supported prosthesis delivery, with follow-up examinations at least 12 months after. Implants were categorized into favorable, questionable, unfavorable, and hopeless, based upon the prognosis categories proposed by Kwok et al. in 2023. Recorded measurements included: age, sex, follow-up duration, initial and latest implant prognoses, supportive care, history of grade C periodontitis, smoking, diabetes, and the use of intravenous bone sparing agents. Descriptive analysis was employed for data interpretation. RESULTS: This study included 651 implants placed in 291 patients. Implants initially classified as having a favorable prognosis exhibited excellent long-term survivability, while those deemed unfavorable at baseline showed the greatest likelihood of deteriorating to a hopeless prognosis. At the latest follow-up, survival rates for implants initially categorized as favorable, questionable, and unfavorable were 100%, 93.5%, and 33.3%, respectively. Cox regression analysis identified initial prognosis, uncontrolled diabetes, and a history of grade C periodontitis as statistically significant risk factors for implant failure, with hazard ratios of 9.70, 35.14, and 66.48, respectively. CONCLUSIONS: The dental implant prognosis system proposed by Kwok et al. is a reliable tool in assessing implant survivability within 5 years. Future research should investigate its long-term performance and the relationship between various influencing factors and implant prognosis.