关键词: 阿司匹林, 拔牙, 牙周炎, 凝血

Abstract: Objective To investigate the influences of aspirin on intra-socket clotting after extractions of tooth with periodontitis at different positions and to analyze the influencing factors.Methods 160 aspirin users (age:50-80 years old,course ＞ 2 week,dosage:100 mg/d) requiring an extraction of one tooth with severe periodontitis were enrolled.The selected teeth included 60 anterior teeth,40 premolars,60 molars and each kind contained 50% maxillary and 50% madibular cases.After pre-extraction Light Transmission Aggregometry (LTA) by Arachidonic Acid (AA) as the inducer,extractions were carried out in all cases without preoperative aspirin suspension and evaluations on clotting of all cases were performed postoperatively according to the Coagulation Classification Table (Class Ⅰ and Ⅱ indicated normal clotting,Class Ⅲ~Ⅴ indicated successively increasing bleeding).Comparisons on post-extraction clotting of all cases and on Platelet Aggregation Rates (PAgT) of cases with normal coagulation were implemented.Furthermore,analyses to anti-platelet effects of aspirin on extraction wounds of different tooth positions and search for potential factors influencing the effect of aspirin were conducted.Results (1) In anterior tooth area,premolar area and molar area,the percentage of cases showing normal clotting after an extraction of one maxillary tooth was 43%,15% and 10% respectively,and that of cases after an extraction of one mandibular tooth was 93%,30% and 20% accordingly.All cases of madibular central and lateral incisors (1, 2) were under Class Ⅰ and Ⅱ,cases under Class Ⅲ and Ⅳ appeared after extractions of a tooth of other positions.In addition,cases under Class Ⅴ were not observed.(2) In anterior tooth area,premolar area and molar area,the PAgT of cases with normal coagulation after an extraction of one maxillary tooth was (14.01±1.05)%,(15.27±0.62)%,(16.83±0.57)% with statistical difference (P=0.037) and that of cases after an extraction of one madibular tooth was (12.83±1.64)%,(13.92±0.87)%,(15.44±0.92)% with statistical difference (P=0.041).Additionally,the PAgTs of normal clotting cases after extractions of an anterior tooth,a premolar and a molar at maxillary dentition were higher than those for normal coagulation after extractions of a mandibular tooth at corresponding position (P=0.028,0.047,0.044 respectively).(3) In cases under Class Ⅲ and Ⅳ,the sclerotin of jaw bones and processus alveolaries adjacent to the sockets was loose with rich blood supply, and the areas of periodontal ligaments around the removed teeth were relatively large.Conclusions (1) Aspirin can exert an anti-coagulation effect on an extraction wound after removal of one tooth with severe periodontitis (except 1,2).(2) For both maxillary and mandibular dentitions,the PAgT required for normal clotting after extraction of an anterior tooth,a premolar and a molar rises successively,so the susceptibility to aspirin effect of extraction site of an anterior tooth,a premolar and a molar increases accordingly.The PAgTs for normal clotting after extractions of a maxillary tooth are higher than those for extractions of a mandibular tooth at corresponding position,so aspirin can lead to more influence on normal coagulation after removal of a maxillary tooth than that after extraction of a mandibular tooth.(3) The blood supply to jaw bones and processus alveolaries around the sockets,the areas of periodontal ligaments around extracted teeth can affect the post-extraction bleeding amount.Since extraction wounds with more bleeding require higher PAgT to achieve normal coagulation,the anti-platelet effects of aspirin on the surgical sites become more obvious.

Key words: aspirin, extraction, periodontitis, clotting