Retrospective Review of Dental Local Anesthetic Induced Paresthesia in the United Kingdom

Background: While local anesthetics are essential drugs in dentistry, risks such as paresthesia are associated with their use. The purpose of this study was to analyze the reported paresthesia cases in the United Kingdom. Methods: Voluntary reports of paresthesia from local anesthetic use between 1998 and 2008 obtained from UK’s Yellow Card Scheme were examined. Statistical significance was tested using the Chi-Square analysis, comparing expected frequencies of paresthesia based on the UK dental anesthetic sales data, to the observed reports of paresthesia. Results: Of the 44 reported cases of paresthesia, 85% of the cases involved the mandible with the lingual nerve being the most often affected. The frequency of observed paresthesia associated with 4% articaine solution, was 5.9 times greater than expected (χ, p<0.0001). Conclusions: These data suggest that paresthesia after the injection of local anesthetic in dentistry is rare, yet more likely to occur if a 4% solution is used.