The floor of the mouth is a very vascular area. Should perforation of the lingual cortex of the mandible occur during the placement of an osseo-integrated implant, significant haemorrhage may result. We present the case of a patient who attended our unit with acute airway obstruction. Although life threatening haematoma following the placement of osseo-integrated implants in the interforaminal area of the mandible is known to occur, there continue to be sporadic reports in the literature. This shows that some practitioners are unaware of the risks involved and place implants of the wrong size and orientation.