CONTEMPORARY RESEARCH IN ENDODONTICS: EVIDENCE-BASED SCIENTIFIC CRITERIA FOR DIAGNOSIS, TREATMENT QUALITY, AND OUTCOME ASSESSMENT

Background Contemporary endodontics is undergoing a transition from technically oriented root canal treatment toward biologically based, evidence-driven, and patient-centred preservation of the natural tooth. The principal objective of endodontic care is no longer limited to mechanical preparation and obturation of the root canal system. Modern treatment aims to establish an accurate pulpal and apical diagnosis, control microbial infection, preserve healthy dental tissues, maintain pulp vitality when biologically possible, restore tooth function, and achieve stable long-term healing. The rapid introduction of cone-beam computed tomography, artificial intelligence, magnification, heat-treated nickel–titanium instruments, activated irrigation, calcium silicate-based materials, guided endodontics, vital pulp therapy, and regenerative procedures has expanded clinical possibilities. However, technological novelty alone cannot be regarded as evidence of therapeutic superiority. New approaches must be assessed using transparent diagnostic standards, biologically relevant outcome measures, appropriate comparison groups, adequate follow-up periods, and validated reporting guidelines. Objective To synthesize contemporary evidence in endodontics and formulate scientific criteria for evaluating diagnostic methods, treatment procedures, biomaterials, digital technologies, and clinical outcomes. Materials and Methods A structured integrative review framework was developed for publications indexed in PubMed/MEDLINE and major professional guideline repositories. Studies and consensus documents published predominantly between January 2020 and August 6, 2026 were prioritized. Earlier landmark publications were included when necessary to explain established biological and methodological principles. The search framework combined the terms “endodontics,” “pulpitis,” “apical periodontitis,” “root canal treatment,” “vital pulp therapy,” “regenerative endodontics,” “cone-beam computed tomography,” “artificial intelligence,” “guided endodontics,” “bioceramic materials,” “treatment outcome,” “core outcome set,” and “reporting guidelines.” Evidence was organized into diagnostic, biological, technological, clinical-outcome, and research-quality domains. Results Modern endodontic evidence supports six interrelated scientific criteria: diagnostic validity, biological plausibility, procedural standardization, tissue preservation, clinically meaningful outcome assessment, and transparent reporting. Clinical symptoms and conventional pulp sensibility tests remain necessary but do not directly measure pulpal blood flow or accurately represent the histological condition of the entire pulp. Cone-beam computed tomography can improve three-dimensional assessment in selected complex cases, but its prescription must be justified by the expected influence on diagnosis or treatment planning. Microbial control remains the biological foundation of root canal therapy. Rubber dam isolation, appropriate access, accurate working-length determination, mechanical preparation, chemical irrigation, prevention of reinfection, and a definitive coronal seal should be treated as interconnected components rather than isolated technical procedures. No instrumentation or irrigation system can guarantee complete sterilization of the complex root canal anatomy. Vital pulp therapy has expanded from the management of reversible pulpitis and immature teeth to selected mature permanent teeth with clinical signs traditionally associated with irreversible pulpitis. Regenerative endodontic procedures may promote continued root development in immature necrotic teeth, although the newly formed tissue does not always reproduce the original pulp–dentine complex. Calcium silicate-based materials, guided endodontics, artificial intelligence, and endodontic microsurgery show significant clinical potential. Nevertheless, many studies remain laboratory-based, retrospective, or methodologically heterogeneous. Endodontic success should therefore be assessed through a combination of pain, signs of infection, tenderness, radiographic healing, function, tooth survival, need for further intervention, adverse events, and patient satisfaction. Conclusions Scientific progress in endodontics should be measured not by the number of new devices or materials introduced into practice but by their ability to improve diagnosis, preserve biological structures, control infection, enhance tooth survival, and produce outcomes that matter to patients. Future studies require standardized diagnostic definitions, prospective designs, adequate sample sizes, calibrated outcome assessment, long-term follow-up, external validation of digital systems, and adherence to endodontic reporting guidelines.