Objective To investigate the expression levels of WBC, CRP, PAB and D-D in patients with odontogenic space infection, and its clinical significance.

Methods The blood samples of 382 patients with odontogenic space infection were collected before surgery and after 4 and 8 day of surgery to measure the levels of WBC, CRP, PAB and D-D and observe their changes. Meanwhile, the clinical parameters such as etiology, number of spaces involved, mouth opening and pain were compared, and the active discharge of pus, dysphagia, sensation of fluctuation, fever and swelling were evaluated. The SPSS 26.0 software package was used to analyze the relationship between WBC, CRP, PAB and D-D levels and various clinical parameters.

Results The levels of WBC, CRP and D-D gradually decreased before the operation, on the 4th day after the operation and on the 8th day after the operation, while the level of PAB gradually increased. Both the VAS score and score of limited mouth opening decreased over time, and the differences were statistically significant (P ＜ 0.01). The CRP, WBC and D-D were positively correlated with degree of pain, while the PAB was significantly negatively correlated with pain (P ＜ 0.05 to P ＜ 0.01). The limitiation of mouth opening was positively correlated with CRP and D-D, and negatively correlated with PAB (P ＜ 0.01). The number of fascia spaces involved before operation was positively correlated with CRP and D-D, and negatively correlated with PAB (P ＜ 0.01), while there was no correlation with WBC (P ＞ 0.05).

Conclusions The combined monitoring of WBC, CRP, PAB and D-D can be effectively used to judge the severity and treatment effects of maxillofacial space infection, and as a reference index to evaluate the prognosis of odontogenic infection.