Background. The authors conducted a prospective, randomized, double-blind, crossover study comparing the degree of pulpal anesthesia achieved by means of mandibular first molar buccal infiltrations of two anesthetic solutions: 4 percent articaine with 1:100,000 epinephrine and 2 percent lidocaine with 1:100,000 epinephrine after an inferior alveolar nerve (IAN) block with the use of 4 percent articaine with 1:100,000 epinephrine.
Methods. Seventy-three blinded adult subjects randomly received buccal infiltrations at the first molar site with a cartridge of 4 percent articaine with 1:100,000 epinephrine at one appointment and a cartridge of 2 percent lidocaine with 1:100,000 epinephrine at another appointment after receiving a standard IAN block with the use of 4 percent articaine with 1:100,000 epinephrine in a crossover design. After the injections, the authors used an electric pulp tester to test the first molar for anesthesia in three-minute cycles for 60 minutes. They considered anesthesia to be successful when two consecutive 80 readings were obtained within 10 minutes of the IAN block and infiltration injection, and the 80 reading was sustained continuously through the 60th minute.
Results. The authors found that with the use of the 4 percent articaine formulation, successful pulpal anesthesia occurred 88 percent of the time for the first molar. With the 2 percent lidocaine formulation, successful pulpal anesthesia occurred 71 percent of the time. The results show a significant difference (P < .05) between the articaine and lidocaine formulations.
Conclusion and Clinical Implications. For a mandibular buccal infiltration of the first molar after a standard IAN block, 4 percent articaine with 1:100,000 epinephrine resulted in a higher success rate (88 percent) than did 2 percent lidocaine with 1:100,000 epinephrine (71 percent success rate).
