Because of causing hyperemia and microbicism and its tonic effect on muscles, iodine iontophoresis has so far been used to soften residual infiltrations, chronic indurations of soft tissue and cervicofacial actinomycosis. In order to evaluate the influence of iodine iontophoresis on therapy of abscesses in the maxillofacial area, we designed a randomized study to investigate the clinical outcome of patients with reflex trismus due to inflammation. Forty-one patients treated by extraoral incision and drainage of the abscess were randomly selected into a group of 21 patients receiving iodine iontophoresis twice a day for 10 minutes beginning at the third postoperative day. Stretching treatment was given to both groups three times a day. Maximal mouth opening was measured daily by the distance of upper and lower incisors. The additional application of iodine iontophoresis accelerated the improvement of mouth opening in the study group in comparison to the control group. Iodine iontophoresis led to an improvement of mouth opening to 100%, compared to 60.6% in the control group at the seventh day of treatment. In-patient treatment time decreased two days in the study group. Therefore, iodine iontophoresis is an effective method of additional treatment in abscesses of the maxillofacial area. Schlagwörter: iodine iontophoresis, abscess