The wound healing after laser surgery is delayed in contrast to conventional scalpel surgery. There are some animal studies, which investigated the effects of laser surgery upon wound healing, whereas clinical investigations on wound healing of human mucous membrane after laser surgery is missing. A histological study on the laryngeal mucosa of 11 patients after laser incisions who underwent emergent laser debulking surgery for acute airway obstruction and a clinical study of 24 patients with oral or oropharynx cancer who were treated by laser surgery were performed to investigate the course of wound healing. The histological findings showed that the beginning of wound healing was delayed after laser surgery. The duration of wound healing after laser surgical tumour resection revealed a clear dependence on the size of the initial defect. The average duration of wound healing after CO(2) laser surgery (32.8 +/- 9.2 days) was significantly shorter than after Nd:YAG laser surgery (40.4 +/- 9.2). Due to the more pronounced zone of necrosis at the base of the wound ground this effect is more evident using the Nd:YAG laser. However, the different course of wound healing with both laser systems does not seem to have a negative influence on functional results.