Objectives This prospective study examined the relationship between resting blood pressure (BP; primary outcome), demographic features of patients, anatomical characteristics of the extracted teeth, surgery variables (secondary outcomes), and acute postsurgical pain in patients undergoing tooth extraction. Materials and methods Standardized surgery was performed under local anesthesia. A composite numerical index, referred to as "postoperative pain/analgesia score" (PPAS), was built out of two intermediate ones, indicating (i) the degree of spontaneous pain reported by the patient (postoperative pain score) and (ii) the amount of analgesic drug intake (postoperative analgesia score). Results A total of 293 patients with complete data sets were included in the analysis. Univariate analysis reveals that the intensity of postoperative pain is related to age, history of hypertension and previous oral surgery, number of extracted teeth, duration of surgery, and extraction of the third molar. On the other hand, there is no relationship with gender, anxiety, and operation duration. Multivariate analysis reveals that the intensity of acute postoperative pain is only associated with the location (upper/lower jaw, P=0.004) and deepness of implantation of the extracted tooth (P<0.0001), and mean resting BP (P=0.031). Conclusions This large prospective study shows that patients with high resting BP had a lower oral postsurgical pain than those with low resting BP. This suggests that high resting BP is a protective factor against oral postsurgical pain. Clinical relevance The measurement of resting BP before surgery may be used in clinical practice to identify patients at risk of developing severe oral postsurgical pain.