Objective: To investigate the speed of action and injection discomfort of 2% lidocaine and 3% prilocaine for upper teeth extractions.
Materials and methods: Forty-six patients were included in the prilocaine 3% group, and 46 in the lidocaine 2% control group. After all injections, soft and hard tissue numbness was objectively gauged by dental probe at intervals of 15 s. Moreover, the pain of the injections was recorded by the patients after each treatment on standard 100 mm visual analog scales, tagged at the endpoints with "no pain" (0 mm) and "unbearable pain" (100 mm).
Results: There were no significant differences in the meantime of first numbness to associated buccal, palatal mucosa, and tooth of patients in the lidocaine and prilocaine buccal infiltration groups (P = 0.56, 0.37, and 0.33). However, clinically, the patients in prilocaine group recorded earlier buccal, palatal mucosa, and teeth numbness than those in lidocaine group. With regards to the discomfort of the needle injections, there was a significant difference for lidocaine and prilocaine groups when comparing the post buccal scores with the post palatal injection scores (t-test: P < 0.001). Lidocaine and prilocaine buccal injections were significantly more comfortable than palatal injections.
Conclusions: Using 2% lidocaine and 3% prilocaine for extractions of upper maxillary teeth produces similarly successful anesthesia. Clinically, prilocaine has slightly rapid onset of action, earlier buccal mucosa, hard palate, and teeth numbness. Prilocaine and lidocaine buccal injection was significantly more comfortable than palatal injection.
Keywords: Dental extraction; injection discomfort; lidocaine; prilocaine; speed of action.