To evaluate the pain relief effect of accessing opening of dental pulp in acute apical abscess with buccal space infection.

From July 2015 to March 2019 in Stomatology Department of Sun Yat-sen Memorial Hospital of Sun Yat-sen University, totally 122 patients suffering intense pain from acute apical abscess of maxillary molars with buccal space infection (71 males and 51 females) were stratified by genders and then randomly divided into two groups, namely the access group (36 males and 25 females) and the control group (35 males and 26 females) . Patients of access group had their pathogenic teeth′s cavities open and drainage before the buccal space incision and drainage as the control group. And visual analogue scale (VAS) was used to record and analyze within 7 d.

Before treatment, VAS scores of the access group and the control group are of no difference (F = 0, P = 0.39) . After buccal space incision and drainage, the VAS score of both groups had decreased within 24 h, with the access group exhibiting a greater decrease immediately and at 30 min, 1 h, 4 h, 12 h and 24 h than the control group did (P<0.001) . Then at 2, 4 and 7 d, VAS scores of the access group exhibited no difference with the control group (P>0.05) , and patients of both groups had their pain relieved.

Accessing opening of the pathogenic teeth′s dental pulp before the buccal space incision and drainage helps effectively in relieving the pain caused by acute apical abscess accompanied with buccal space infections.