Quantitative Percussion Diagnostics (QPD): Seeing What the Eye Can't With Objective Structural Data

Background Clinical assessment of the structural integrity of teeth, restorations, and dental implants remains largely subjective, relying on radiographs, tactile evaluation, and unmeasured percussion. These methods often fail to identify early biomechanical or adhesive failure, allowing deterioration to progress asymptomatically until fracture, restoration failure, or implant complications occur. An objective, radiation-free diagnostic method capable of identifying early micromobility may improve preventive and restorative outcomes. This article is a narrative review of Quantitative Percussion Diagnostics (QPD™) and its applications in clinical practice in improving diagnostics that are not evident radiographically or with standard examination methods. Methods This review describes the clinical principles and applications of an FDA-cleared diagnostic system utilizing QPD™ to measure overall and internal mobility of teeth and implants. The system applies a brief, controlled mechanical impulse and analyzes the resulting response using two quantitative metrics: a mobility score reflecting overall micromobility of the site, and the normal fit error (NFE) reflecting localized internal micromobility of the site. Representative clinical cases demonstrate applications in crack detection, evaluation of failing restorations, implant stability assessment, monitoring of osseointegration, periodontal screening, occlusal overload assessment, and post-endodontic evaluation. Results As reported in over 30 peer-reviewed multidisciplinary studies in dental, engineering, and computer science journals, QPD™ identifies early structural compromise, including cracks, adhesive failure, internal restoration breakdown, implant component instability, and early biomechanical overload, that was not evident on routine radiographic or clinical examination. Quantitative measurements enabled baseline establishment, longitudinal monitoring, and objective confirmation of treatment outcomes following restorative, occlusal, periodontal, and implant interventions. Incorporation into routine examinations and hygiene visits was feasible without increasing chairside time. Conclusions QPD™ provides an objective, reproducible, and radiation-free approach for evaluating the structural integrity of teeth, restorations, and implants. This is based on decades of research from broad interdisciplinary teams of dentists, engineers, data scientists, and statisticians. By detecting early micromobility before the onset of clinical symptoms, this technology supports a preventive diagnostic paradigm, facilitates minimally invasive intervention, enhances patient communication, and contributes to improved long-term restorative and implant success.