To compare the clinical performance of a modified implantable closed irrigation negative-pressure drainage technique with traditional vacuum sealing drainage (VSD) and conventional open drainage in patients with odontogenic descending necrotizing mediastinitis (DNM).

This retrospective cohort study included 94 patients with odontogenic DNM treated between 2015 and 2025. Patients were assigned to modified VSD ( n = 32), traditional VSD ( n = 31), or conventional drainage (control, n = 31). The primary outcome was ICU length of stay. Secondary outcomes included duration of intubation, tracheostomy rate, inflammatory marker recovery, drainage-related performance, and in-hospital mortality. Multivariable regression was used to adjust for baseline and temporal confounders.

Both the modified VSD group and the traditional VSD group had shorter ICU stay compared with the control group (median 6.0 vs 8.0 vs 13.0 days; P < 0.001), with no significant difference between the two VSD groups on post-hoc comparison. Additionally, the modified VSD group had shorter intubation duration than the other two groups (5.5 vs 8.0 vs 12.0 days; P < 0.001). The modified technique also demonstrated lower seal leakage rate (6.3%vs 29.0%; P = 0.017) and greater daily drainage capacity (2171.9 ± 393.7 vs 609.7 ± 266.3 mL/day; P < 0.001). Inflammatory markers recovered faster in both VSD groups than in controls, with earlier WBC decline in the modified group ( P = 0.006). In multivariable analyses, modified VSD remained independently associated with shorter ICU stay (aMR = 1.26; P = 0.024) and shorter intubation (aMR = 1.32; P = 0.005). Tracheostomy rates and mortality did not differ significantly.

Modified VSD technique was associated with improved drainage performance, faster inflammatory recovery, shorter intubation duration, and shorter ICU stay compared with conventional approaches.