Maxillary infiltration anaesthesia by ropivacaine for upper third molar surgery.

The main purpose of this study was to assess the clinical efficacy and haemodynamic effects of ropivacaine for infiltration anaesthesia in patients undergoing surgical removal of upper third molars. The safety profile of ropivacaine was also studied by investigating the maximal venous plasma concentration of ropivacaine and the reactivity to ropivacaine of isolated human infraorbital arteries. Ropivacaine in concentrations of 0.5, 0.75 and 1% achieved dose-dependent parameters of maxillary infiltration aneasthesia, clinically relevant in concentrations 0.75 and 1%. Postoperative needs for analgesics were observed in 67-100% of patients. Haemodynamic parameters were stable during surgery with significant changes occuring 10 min after surgery. After maxillary infiltration of 2.0 ml 1% ropivacaine, the maximum venous plasma concentration (Cmax) was 82+/-15 microg/l. On isolated human infraorbital artery, ropivacaine (10(-4)M) induced endothelium-independent contraction. This study suggests that 0.75 and 1% ropivacaine offers adequate and safe intraoperative analgesia but not successful postoperative pain control for the surgical removal of upper third molars.