RESUMEN
OBJECTIVES: To investigate the success rate of supplemental intraseptal and buccal infiltration anaesthesia in mandibular molars undergoing endodontic therapy/extraction when the inferior alveolar nerve block has failed. MATERIAL AND METHODS: A prospective clinical trial including 200 patients undergoing lower molar root canal treatment/teeth extraction was conducted. Only 80 patients of the participants who had profound lower lip anaesthesia after the administration of inferior alveolar nerve block (IANB) were in pain within treatment. Patients experiencing moderate to severe pain upon using elevators, forceps, bur, or endodontic file were randomly allocated to the 2% lidocaine intraseptal injection and 4% articaine buccal infiltration groups. Level of pain was assessed every 2 to 10 min on standard 100 mm visual analogue scales. RESULTS: Overall, 55 (69%) of patients who were given either intraseptal injection of 2% lidocaine or buccal infiltration of 4% articaine had successful anaesthesia of lower molar teeth within 10 min. However, 25 (31%) of participating patients in the buccal infiltration and the intraseptal groups had failed anaesthesia within the study duration (10 min), and they received additional local anaesthetic. IANBs were more painful than buccal and intraseptal injections. However, buccal articaine injections were significantly more comfortable than intraseptal lidocaine injections (P > 0.001). CONCLUSIONS: Supplemental intraseptal injection of 2% lidocaine and buccal infiltration of 4% articaine achieved profound pulpal anaesthesia in 69% of patients when the inferior alveolar nerve block failed. Recommendations can be given to dental practitioners to use infiltration of 4% articaine in conjunction with intraseptal injection of 2% lidocaine to anaesthetize the lower molar teeth when inferior alveolar nerve block fails.
RESUMEN
OBJECTIVES: To investigate the efficacy of retreatment and reciprocating rotary systems in removing gutta-percha filling material from root-canal systems. METHODS: A total of 90 single-canal human teeth were instrumented using a F3 ProTaper file and obturated with gutta-percha and the Tubliseal sealer using the lateral-compaction technique. They were divided into five groups according to the rotary system used to remove the filling material: Reciproc, which used the Reciproc-R25 file; WaveOne, which used the WaveOne-Primary file; S1, which used the S1 (25/.06) file; ProTaper-R, which used the ProTaper-Retreatment system; and Mtwo-R, which used the Mtwo®-Retreatment system. The time required to remove the filling material (min) and the associated instrument separation, if any, were recorded. Teeth were cleaved longitudinally and photographed with a high-resolution camera. Images were imported to the AutoCAD application to measure the remaining filling material and the root-canal space. Data were analysed using the one-way analysis of variance and Chi-squared tests. RESULTS: The Mtwo-R group showed the highest mean remaining filling material (51%) (p < 0.001), with no significant differences among the other groups. The ProTaper group required the least time for filling-material removal (4.95 min), with significant differences compared to the other groups (p < 0.05), except the WaveOne group (5.83 min; p = 1.000). Overall, 13 instruments (15.9%) were used for filling-material removal, with a significantly greater proportion in the Mtwo-R group (33.3%) compared to the other groups (p = 0.009). CONCLUSIONS: Within the limitations of this in vitro study, reciprocating rotary systems were as effective as retreatment rotary systems in removing root-canal filling material. The Mtwo-R system showed the poorest performance with respect to removal effectiveness and instrument separation.