Association of periodontitis severity and tooth loss with gastric cancer: a cross-sectional study.

This comparative cross-sectional study aimed to determine the association between periodontitis severity and tooth loss (TL) with gastric cancer (GC) in adult patients. It was conducted between February and April 2025 at the "Virgen de la Puerta" High-Complexity Hospital and the "Dr. Luis Pinillos Ganoza" Regional Institute of Neoplastic Diseases - IREN NORTE in Trujillo (Peru). A total of 240 adult patients were evaluated: 120 without gastric cancer (NGC) and 120 with GC. Inter- and intra-rater calibration was performed to diagnose periodontitis, tooth loss, bleeding on probing (BOP), and dental plaque control (DPC). GC was diagnosed by the hospital's specialist oncologist. Statistical analysis included bivariate and multivariate models, with a significance level of P < 0.05. Results showed an association between periodontitis severity and GC (P = 0,001); nevertheless, there was no association between TL and GC (P = 0.966). The GC prevalence increased among patients with severe periodontitis (P < 0.0001), among men (P = 0.027), and among those aged <70 years. In conclusion, severe periodontitis is associated with GC, whereas TL is not.