Background: The basis for the proposed preventive rounding of plunging or pointed cusps is that the occlusal modification will help to reduce stagnation of plaque, the traumatic contact and resulting caries. This has not been proven clinically. Objective: To assess the recent evidence and consider if a longitudinal clinical study is scientifically and ethically warranted. 
Methods: Structured review of English literature published from 2017 to August 2026 in the PubMed database with a focus on caries biology, occlusal and fissure morphology, plaque retention, occlusal adjustment, minimally invasive dentistry and preventive alternatives. 
Results: Several clinical studies, such as a 5-year cohort, have shown that deep fissure morphology is associated with increased plaque accumulation and increased caries risk. None of the longitudinal cohorts or RCTs found were appropriate, however, to directly test the hypothesis of rounding of sound pointed or plunging cusps for reduction of caries incidence as a prophylactic measure. Modern occlusal-adjustment studies focus not on caries, but on masticatory function, TMJ disorders or periodontal results. Today, caries recommendations focus on biofilm management, dietary influences, and fluoride application, as well as fissure sealing and retention of remaining tooth structure. 
Conclusion: Prophylactic cusp rounding cannot presently be recommended as an evidence-based caries-preventive procedure. In the event of investigation, it has to be clinically equipoise, with minimal irreversible enamel removal, pre-specified safety outcomes, blinded caries assessment, and long-term follow-up against accepted conservative prevention.