TMU J Dent. Vol. 5 Issue 4. October - December 1 TO COMPARE THE ANAESTHETIC EFFICACY OF TWO SUPPLEMENTAL TECHNIQUES OF LOCAL ANAESTHETIC INJECTION AFTER THE FAILURE OF THE PRIMARY INFERIOR ALVEOLAR NERVE BLOCK IN MANDIBULAR MOLARS: AN IN VIVO STUDY Deeksha Khurana 1 , Ashwini B Prasad 2 , Jaya Purewal 3 , Deepak Raisingani 4 , Charu Vyas 5 , Akansha Jharwal 6 Post Graduate 1,3,5,6 Professor 2,4 1-6- Department of Conservative Dentistry and Endodontics, Mahatma Gandhi Dental College and Hospital, Jaipur, Rajasthan , India INTRODUCTION Achieving profound anaesthesia of pulp is a key stone in endodontic practice. Fear and anxiety associated with endodontic treatment is reduced with effective pain management. 1 To achieve local anaesthesia for mandibular teeth ,inferior alveolar nerve block (IANB) with 2% lidocaine is the commonly employed injection technique. 2 However, this IANB technique does not always result in successful pulpal anaesthesia especially in emergency cases of irreversible pulpitis and is associated with a high failure rate (Hargreaves & Keiser 2002, Aggarwal et al. 2009, Argueta-Figueroa et al. 2012). 3-7 The various clinical studies done in endodontics have reported the failure rate of IANB varying from 44% to 81 %. 3 Thus, it becomes challenging to manage endodontic emergencies associated with irreversible pulpitis in mandibular molars. This is generally managed with the help of the supplemental anaesthetic techniques like intraosseous, intra-ligamentary or intrapulpal injections, 7 as it has been reported that these supplemental techniques improve the efficacy of anaesthesia when a primary IANB injection fails (Hargreaves & Keiser 2002, Meechan 2002). 3,8 An intraosseous or intraligamentary injection can be used to deposit the local anaesthetic solution into the cancellous bone in the vicinity of tooth apex thus improving the Efficacy of anaesthesia.(Hargreaves.(Hargreaves & Keiser 2002, Meechan 2002). 3 A special equipment for drilling the cortical bone is required for an intraosseous injection thus is not a preferred technique. In intraligamentary injection local anaesthetic solution is forced through the cancellous bone so that it diffuses to the apex through the bony perforations and gets deposited into the periodontal ligament space. 9 Another commonly employed supplemental injection is the intrapulpal injection, which is administered under back pressure, and is a preferred technique in patients who experience pain or discomfort on pulp extirpation. 10 According to Birchfield and Rosenburg, efficacy of intrapulpal technique is dependent on the back-pressure with which the anaesthetic solution is injected and not the type of the solution which is injected. 11 Materials and Methods The study was conducted after obtaining approval from the institutional ethics committee. Sixty patients participated in the study, out of which there were 33 men and 27 women. The patients were selected in the age group between 18 and 50 years and between 18 and 50 years and with overall sound systemic conditions. Each patient had a mandibular molar with continuous pain, but vital pulp as determined by a Original Research Abstract Profound analgesia is essential for vital pulp extirpation in endodontics. The inferior alveolar nerve block (IANB), used for mandibular injection does not always result in profound anaesthesia of pulp, especially in cases of irreversible pulpitis. To manage such situations supplemental injections are being used. Thus the present study was undertaken to evaluate the efficacy of two supplemental techniques (intraligamentary and intrapulpal) of local anaesthetic injection after the failed primary inferior alveolar nerve block in mandibular molars with irreversible pulpitis. Materials and Methods: Patients were given IANB with 1.8mL of 2% lignocaine with 1:200,000 epinephrine. Heft-Parker visual analog scale (HP VAS) was used to assess the pain. The IANB was considered successful if patients allowed endodontic access or instrumentation with no or mild pain (HP VAS score < 55 mm). While patients with‘moderate-to-severe’ pain (HP VAS score ≥ 55 mm) were randomly divided into 2 groups and received intraligamentary injection (group 1) and intrapulpal injection (group 2). Root canal treatment was re- initiated. Again, absence of pain or weak/mild pain on endodontic access preparation or instrumentation indicated the success. Results: The obtained data was statistically analysed using unpaired t test. The difference between the two techniques was found to be stastically insignificant. Conclusion: Both the techniques i.e intrapulpal and intraligamentary are equally effective in achieving adequate anaesthesia after the primary IANB fails and thus either of the technique can be used in such cases. Key Words: Inferior alveolar nerve block, Irreversible pulpitis, Local anaesthesia, Mandibular molars.