Objective Evaluation on the effect of single tooth anesthesia（STA） computer-controlled local anesthetic delivery in tooth extraction to the patients with dental anxiety and cardiovascular disease.Methods Two groups were included. In the experimental group, STA was used, and in the control group, hand injection was performed. Anxiety level before and after injection was evaluated with modified dental anxiety scale. The level of pain during injection was assessed with visual analogue scale by patients after injection. Blood pressure and heart rate were observed before, during and after injection.Results The visual analogue scale value showed a statistical difference between the experimental group and the control group. After injection, 86.11% patients in experimental group were decreased about the incidence rate of scores, which was significiantly superior to control group. No changes in blood pressure and heart rate were found before, during and after injection in the experimental group. The blood pressure increased significantly during injection in the control group.Conclusion STA computer-controlled local anesthetic delivery can abate the inject pain and anxiety level, reduce the risk in the operation.
