Introduction

Successful local anaesthesia is the basis of endodontic management of symptomatic teeth. However, dental anesthetic injections have a limited success rate in the first attempt (1–3). The success rate further decreases with the presence of preoperative pain (4). The inferior alveolar nerve block (IANB) is particularly notorious for high anesthetic failure rates, especially in teeth associated with symptomatic pulpitis (5). To achieve painless treatment in patients with a failed primary IANB, supplementary anaesthesia has been advised. Supplementary intraligamentary (or periodontal injections) and intraosseous injections have shown promising results (6).  The supplementary injections aim to deposit the local anaesthetic solution in the cancellous bone close to the root apex. An intraligamentary injection is a form of intraosseous injection since the local anaesthetic solution is forced via perforations in the dental socket to the cancellous bone around the root (7).

Tramadol hydrochloride is a centrally acting opioid analgesic (8). It is known to be effective in the treatment of moderate to severe types of pain (9,10). Several researchers have conducted both in vitro and in vivo studies to test the local anaesthetic (LA) effect of tramadol (10–14). A study has reported that tramadol alone or in combination with adrenaline can be used as a local anaesthetic for the extraction of the upper molar tooth under a subperiosteal infiltration (15).

Review of literature: It has been reported that the presence of a vasoconstrictor significantly increases the duration and efficacy of the intraligamentary injection field field(16). Success rates of up to 92% have been reported with both pressure type and conventional syringes (4). The intraligamentary injection was introduced by Malamed in 1982 as an alternative to the conventional inferior alveolar nerve block (17). Since then it has been evaluated both as a primary injection and as a supplementary injection, Kaufman et al compared the anaesthetic efficacy of plain 2% lidocaine with 2% lidocaine with 1:50,000 epinephrine (18). The authors reported that the duration of anaesthesia with plain lidocaine was 1.02 min, while lidocaine with epinephrine had pulpal anaesthesia of 27.05 min. Johnson et al compared the duration of anaesthesia of 1.5% etidocaine with 1:200,000 epinephrine and 2% lidocaine with 1:100,000 epinephrine given as an intraligamental injection (19). Etetidocaine gave 35% whereas lidocaine gave 55% success rates. The authors suggested that the anaesthetic efficacy in intraligamentary injections was more related to the concentration of epinephrine than the type of anaesthetic agent. Meechan (2002) evaluated the anaesthetic efficacy of 2 different concentrations of plain ropivacaine vs. lidocaine containing epinephrine when given as a primary intraligamentary injection and reported that lignocaine with epinephrine was more effective than ropivacaine (20). A study evaluated the efficacy of local anaesthesia using tramadol hydrochloride (HCl) with versus without adrenaline in the extraction of upper molar teeth (15). The authors suggested that suggest tramadol HCl in combination with adrenaline can be used as an alternative local anaesthetic. The majority of the studies evaluating intraligamentary injections have been performed on asymptomatic teeth. Very limited research has been dedicated to the evaluation of different variables in intraligamentary injections in patients with symptomatic irreversible pulpitis.

 Aim :

1.      To compare the anaesthetic efficacy/ success rate of 2% lidocaine with 1: 80 000 epinephrine vs. 2% lidocaine with 1:80 000 epinephrine plus tramadol hydrochloride (50 mg, 1:1 v/v ratio) given as a supplemental intraligamentary injection after a failed primary inferior alveolar nerve block.

Objective :

 1. To achieve painless treatment in patients with a failed primary IANB. during the endodontic management of symptomatic mandibular first/second molar.

 2..To evaluate the heart rate during and after intraligamentary injections.

The null hypothesis will be that different anaesthetic solutions have no effect on the anaesthetic success rate or the heart rate.

Materials and Methods :

Methodology:  Prospective, randomized, double-blind clinical trial

Site:  Conservative Dentistry, Faculty Of Dentistry, Jamia Millia Islamia 

              N: 30 patients in each group, total 60 patients

 Patients experiencing a failed primary IANB shall be enrolled on the study. The initial failure will be defined as pain (score more than 54 on Heft Parker Visual  Analog Scale (VAS) during access cavity preparation or at root canal instrumentation stage (21). The primary outcome (endpoint) will be defined as “success or failure” which will be indicated as the ability to undertake pulp access and canal instrumentation with no or mild pain. The secondary outcome will be the evaluation of heart rate after supplementary intraligamentary injections.

                   A tentative sample size calculation has been performed using data from a previous study, keeping the α level type I error at 0.05 for a single-tailed test and β level type II error at 0.20.¹⁹ The analysis indicated that a sample size of 30 subjects would give 80% power to detect a 25% difference in the success rates of the two different supplemental intraligamentary injections. For heart rate analysis, it has been calculated that a minimum of 23 patients per group shall be required to detect a difference of 10 beats per minute (with a baseline heart rate of 72 beats per minute).

                 The treatment procedure and the use of pain scales will be explained to the patients. A combined VAS, the Heft-Parker scale (HP VAS), will be used in the present study (21).

Inclusion criteria:

1. Symptomatic carious exposed mandibular first or second molars.
2. Positive and prolonged response to thermal sensitivity tests and electric pulp test.
3. Vital coronal pulp on access cavity preparation.
4. American Society of Anesthesiologists class I or II medical history.
5. Ability to understand the use of pain scales.

Exclusion criteria

a.       Active pain in more than 1 tooth.

b.      Teeth with fused roots.

c.       Radiographic evidence of an extra root.

d.      Large restorations with overhanging margins.

e.       Full crowns or deep periodontal pockets.

f.       Known allergy or contraindications to any content of the local anaesthetic solution.

g.      History of known or suspected drug abuse.

h.      Taking any drugs which could affect the pain perception, e.g, opioids, antidepressants, anticonvulsants, muscle relaxants, anxiolytics, sedatives, NSAIDs. ²³

i.        Pregnant or breastfeeding patients.

All patients will receive a primary IANB injection using 1.8 mL of 2% lidocaine with 1: 80 000 epinephrine using a direct Halsted approach. The needle will be inserted until bony resistance will be felt. After reaching the target area, aspiration will be performed, and the solution will be deposited over a period of 60 seconds. After 10 minutes, the patients will be asked about lip numbness. Patients without profound lip numbness will be excluded from the study since the block will be considered ‘missed’. A conventional access opening will be initiated after isolation with a rubber dam. Patients will be instructed to raise their hands if any pain will be felt during the procedure. In case of pain during treatment, the procedure will be stopped, and the patients will be asked to rate the pain on the HP VAS. The patients with failed primary IANB will receive supplementary intraligamentary injections of 2% lidocaine with either 1:80 000 or 2% lidocaine with 1:80 000 epinephrine plus tramadol hydrochloride (50 mg, 1:1 v/v ratio). The cartridges will be masked with an opaque tape and will be coded with an alpha-numeric code. The code will be broken only after the completion of the study. The patients will be randomly allocated to two treatment groups (n=60, 30 patients per group) with the help of an online random generator. The rubber dam will be removed and the site of the injection will be cleaned with an antiseptic solution. The resting heart rate will be monitored with a finger pulse oximeter by a faculty member. The first group will receive intraligamentary injections of 2% lidocaine with 1: 80 000 epinephrine. The injections will be administered using a pressure-type syringe (Osung Deosy, Pearland, Tx, USA) and 30 gauge short needles (Septojet needles, Septodont). The second group will receive intraligamentary injections of 2% lidocaine with 1:80 000 epinephrine plus tramadol hydrochloride (50 mg, 1:1 v/v ratio). In both groups, a total of 1.2 mL of anaesthetic solution will be deposited. The heart rate will be measured at 15-second intervals till 5 minutes after intraligamentary injections. Success will be again defined as no pain or faint/weak/mild pain during endodontic access preparation and instrumentation.

Statistical analysis: The results will be tabulated in contingency tables. The age of patients will be analyzed using the Mann-Whitney U test at P < .05. The gender and distribution of teeth will be analyzed using 2X2 contingency tables and chi-square tests. The anaesthetic success rates will be analyzed with the Pearson chi-square test. The heart rate changes will be analyzed using a t-test.

Source of funding: None

Conflicts of interest: None

Work schedule: the study is expected to be completed in 2 months

Technical support required: None

References

1.         Hargreaves KM, Keiser K. Local anesthetic failure in endodontics:. Mechanisms and Management. Endod Top. 2002 Mar;1(1):26–39.

2.         Berlin J, Nusstein J, Reader A, Beck M, Weaver J. Efficacy of articaine and lidocaine in a primary intraligamentary injection administered with a computer-controlled local anesthetic delivery system. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2005 Mar;99(3):361–6.

3.         Bigby J, Reader A, Nusstein J, Beck M, Weaver J. Articaine for supplemental intraosseous anesthesia in patients with irreversible  pulpitis. J Endod. 2006 Nov;32(11):1044–7.

4.         Claffey E, Reader A, Nusstein J, Beck M, Weaver J. Anesthetic Efficacy of Articain for Inferior Alveolar Nerve Blocks in Patients with Irreversible Pulpitis. J Endod. 2004 Aug;30(8):568–71.

5.         Claffey E, Reader A, Nusstein J, Beck M, Weaver J. Anesthetic efficacy of articaine for inferior alveolar nerve blocks in patients with irreversible pulpitis. J Endod. 2004 Aug;30(8):568-71. 

6.         Atbaei A, Mortazavi N. Prophylactic intraligamentary injection of piroxicam (feldene) for the management of post-endodontic pain in molar teeth with irreversible pulpitis. Aust Endod J. 2012 Apr;38(1):31–5.

7.         Becker DE, Reed KL. Local Anesthetics: Review of Pharmacological Considerations. Anesth Prog. 2012;59(2):90–102.

8.         Mane RJ, Choi JJE, Sharpe-Davidson WF. Tramadol as a local anaesthetic agent in dentistry: A systematic review of local and systemic adverse effects. Saudi Dent J. 2021 Dec;33(8):842–52.

9.         Aksoy F, Ege B. The effect of pretreatment submucosal injections of tramadol and dexamethasone on post-endodontic pain in mandibular molar teeth with symptomatic irreversible pulpitis: a randomized controlled clinical trial. Int Endod J. 2020 Feb;53(2):176–85.

10.       Collins M, Young I, Sweeney P, Fenn GC, Stratford ME, Wilson A, et al. The effect of tramadol on dento-alveolar surgical pain. Br J Oral Maxillofac Surg. 1997 Feb;35(1):54–8.

11.       Ahmad Qureshi A, Mousa Bakri M. Comparative study of local anesthetic efficacy of 5% tramadol versus 2 %Lignocaine with 1:100,000 adrenaline for extraction of fully erupted maxillary 3rd molars using infiltration anesthesia. Saudi Dent J. 2022 May;34(4):306–9.

12.       Ege B, Calisir M, Al-Haideri Y, Ege M, Gungormus M. Comparison of Local Anesthetic Efficiency of Tramadol Hydrochloride and Lidocaine Hydrochloride. J Am Assoc Oral Maxillofac Surg. 2018 Apr;76(4):744–51.

13.       Ong CKS, Lirk P, Tan JMH, Sow BWY. The analgesic efficacy of intravenous versus oral tramadol for preventing postoperative pain after third molar surgery. J Am Assoc Oral Maxillofac Surg. 2005 Aug;63(8):1162–8.

14.       Shipton EA, Roelofse JA, Blignaut RJ. An evaluation of analgesic efficacy and clinical acceptability of intravenous tramadol as an adjunct to propofol sedation for third molar surgery. Anesth Prog. 2003;50(3):121–8.

15.       Al-Haideri YAA. Comparison of local anesthetic efficacy of tramadol hydrochloride (with adrenaline) versus plain tramadol hydrochloride in the extraction of upper molar teeth. J Am Assoc Oral Maxillofac Surg. 2013 Dec;71(12):2035–8.

16.       Aggarwal V, Singla M, Miglani S, Kohli S. Comparison of the anaesthetic efficacy of epinephrine concentrations (1 : 80 000 and 1 : 200 000) in 2% lidocaine for inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: A randomized, double-blind clinical trial. Int Endod J. 2014;47(4).

17.       Malamed SF. The periodontal ligament (PDL) injection: An alternative to inferior alveolar nerve block. Oral Surg Oral Med Oral Pathol. 1982 Feb;53(2):117–21.

18.       Kaufman E. Transligamentary anesthesia: a review. Anesth Pain Control Dent. 1992;1(3):133–41.

19.       Johnson TM, Badovinac R, Shaefer J. Teaching alternatives to the standard inferior alveolar nerve block in dental education: outcomes in clinical practice. J Dent Educ. 2007 Sep;71(9):1145–52.

20.       Meechan JG. A comparison of ropivacaine and lidocaine with epinephrine for intraligamentary anesthesia. Oral Surg Oral Med Oral Pathol Oral Radiol Endod. 2002 Apr;93(4):469–73.

21.       Heft MW, Parker SR. An experimental basis for revising the graphic rating scale for pain. Pain. 1984 Jun;19(2):153–61.