Objectives: The purpose of this study was to evaluate the anesthetic efficiency of local infiltration anesthesia administered with a pressure syringe (P-INF) via a special technique versus direct block anesthesia of the inferior alveolar nerve (IANB) for tooth extraction in the posterior mandible.
Materials and methods: In a prospective randomized study, 101 teeth in 101 patients were extracted in the posterior mandible under local anesthesia whereby two different administration techniques were used (P-INF n = 48; IANB n = 53). Primary objectives were comparisons of anesthetic success rate (yes/no) and efficacy (full/sufficient vs. insufficient). Secondary objectives were patients' pain perception during treatment, pain of injection (numerical rating scale), need for second injections (always IANB), time until onset of anesthetic action (min), and duration of local numbness (min).
Results: IANB was successful in all cases, whereas initial P-INF achieved 35% of success only. Furthermore, IANB reached significant higher values of anesthetic efficacy compared to P-INF (P < 0.001). Concerning pain of injection, patients rated IANB to be more painful (P = 0.039). Second injections were significantly more often necessary for P-INF (P = 0.006) whereas duration until onset of action as well as the duration of local numbness were found to be equal.
Conclusions: For anesthetic efficacy as well as anesthetic success, block anesthesia of the inferior alveolar nerve (IANB) turned out to be more proficient to local infiltration via special delivering system with a special technique.
Clinical relevance: Infiltration, even when performed with 4% articaine and a pressure syringe system, is not a suitable method of anesthesia in the posterior mandible.
Keywords: Anesthetic success; IANB; Local anesthesia; Mandibular molar tooth extraction; Molar region of the mandible; Pressure syringe system.