The purpose of this study was to determine the anesthetic efficacy of a intraosseous anesthesia (IOA) as an alternative to the infra alveolar nerve block (IANB) or the maxillary anesthesia. 55 subjects who underwent a tooth extraction received a primary X-tip intraosseous injection (LLC Lakewood, New Jersey, U.S.A.) of Ubistesin forte (articaini hydrochloridum 40 mg, adrenalinum 10 pg ut adrenalini hydrochloridum 1:100000, median 1.5 ml). A pulse oximeter measured the heart rate and the oxygen saturation. The results demonstrated, that the maximum heart rate was higher with the intraosseous injection (average 14.6 beats/min increase) during 1.5-2 minutes, but there was no depression of the oxygen saturation. The wound healing was uneventful. We registered five non-responders which were treated additionally with 1.3 ml of Ubistesin forte terminal anesthesia. For all patients the IOA was unpleasant similar to a "normal" anesthesia. Success of the intraosseous injection was 91%, comparable to the study of Turner et al. (2002) (or the clinical experience after an IANB). For non-responders to an IANB the IOA seems to be a good alternative method.