UCSF

Objective: This short-term prospective pilot study aims to assess the validation of the patient-centered implant risk assessment tool in patients recruited at the University of California, San Francisco (UCSF) School of Dentistry.Materials and Methods: Patients seen in the university periodontal clinics were enrolled into the study based on their eligibility for dental implant treatment. Dental surgeons completed a survey tool, called the Implant Risk Assessment Questionnaire (RAQ), for each implant placed. After at least 6 months of loading with the implant final prosthesis, patients were seen for a recall visit at which point, the implant was diagnosed as healthy or having peri-implant disease. Peri-implant disease was subcategorized as peri-implant mucositis, and peri-implantitis. The survey output classifies the implant as low, medium, or high aggregate risk, which was correlated to diagnoses of healthy, peri-implant mucositis, or peri-implantitis respectively. The RAQ scores and diagnoses were used to compute sensitivity, specificity, positive and negative predictive values to determine the tool validity.

Results: Forty-two subjects with 116 implants were recruited into the study. Thirty-eight of these implants were restored by the conclusion of the study, and of those, 28 were seen for follow-up at least 6 months after final prosthesis delivery. Eleven implants were diagnosed as healthy, sixteen as peri-implant mucositis, and one as peri-implantitis with a follow up between 6 -14 months (mean follow-up of 7.71 months). Four implants had early failures prior to the prosthesis delivery. Sensitivity, specificity, positive and negative predictive parameters were initially low, indicating a low predictive value of the RAQ tool. These parameters were improved by omitting questions which were lowering the predictive ability of the test within this time frame. Questions on restoration type, biologic width, treated periodontitis, tissue phenotype, maxillary posterior implant position, and clinician experience were removed to improve validity parameters for this short-term pilot study. Sensitivity was maintained at 82.4%, specificity improved from 0 to 45.5%, positive predictive value increased from 57.7% to 70%, and negative predictive value increased from 0% to 62.5% when comparing before and after the omission of these questions. Conclusion: In a short-term context, the RAQ survey tool may have limited utility in its original form to identify cases of health and disease, but if modified to omit certain risk categories, its predictive capacity may be increased. These risk questions or categories may regain relevance for their contribution to peri-implant disease as the study follow-up is extended.