Abstract
BACKGROUND: Periodontal inflamed surface area (PISA) and masticatory efficiency have been used to evaluate the relationship between systemic diseases and oral diseases. However, clear standards for PISA values and masticatory efficiency in relation to the severity of periodontitis are lacking. This study aims to evaluate PISA values and masticatory efficiency based on the 2018 periodontal status classification system. METHODS: In total, 153 healthy participants diagnosed with periodontitis were included in the study. The diagnosis was based on the 2018 periodontal status classification. PISA values and masticatory efficiency were measured at baseline and after initial periodontal therapy. RESULTS: PISA demonstrated a higher area under the curve for Stage III (0.815) and Grade B (0.85). At baseline, PISA was showed significant negative correlation with masticatory efficiency (B coefficient [95% CI]: -0.02 [-0.03, -0.006], p < 0.01). Following periodontal therapy, both PISA values and masticatory efficiency showed significant improvements, with median PISA values changing from 856 at baseline to 277.5 after treatment, and mean masticatory efficiency increasing from 153.3 to 166.9. After initial periodontal therapy, PISA values were significantly higher in patients classified as Stage IV and Grade C compared to those with other stages and grades. Age exhibited a significant negative correlation with changes in PISA (B coefficient [95%CI]: -11.8 [-20.3, -3.19]), and change in PISA value was significantly positively related to the increase in masticatory efficiency (B coefficient [95%CI], 0.02 [(0.0002, 0.03]). In patients with periodontitis, changes in periodontitis classification were associated with increased PISA values and decreased masticatory efficiency. CONCLUSION: Periodontal therapy improved PISA and masticatory efficiency values. However, the extent of improvement was less pronounced in patients with higher stages and grades of periodontitis. It is essential to consider the interplay between increased PISA and decreased masticatory efficiency when treating patients with severe periodontitis. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1186/s12903-025-06456-7.