A prospective, randomized single-blind evaluation of effect of injection speed on anesthetic efficacy of inferior alveolar nerve block in patients with symptomatic irreversible pulpitis

Present status and future directions - Mechanisms and management of local anaesthetic failures

Pain control during root canal treatment is of utmost importance for both the patient and the dental practitioner and many studies have investigated ways of overcoming problems with gaining adequate anaesthesia during treatment. The PubMed and Cochrane databases were searched for evidence-based studies regarding local anaesthesia for root canal treatment. Many variables, including premedication, pain during needle insertion, pain on injection, premedication with various types of drugs, volume of anaesthetic solutions, supplemental anaesthetic techniques, and additives to the anaesthetic solutions, may influence pain perception during root canal treatment. Differences between teeth with healthy pulps versus those with irreversible pulpitis should be considered when the effects of variables are interpreted. There are several concerns regarding the methodologies used in studies that have evaluated anaesthesia success rates. There are some conditions that may help to predict a patient's pain during root canal treatment and these conditions could be overcome either by employing methods such as premedication with a non-steroidal anti-inflammatory drug prior to the treatment visit or by using supplementary anaesthetic techniques before or during the treatment. However, authors need to be more careful when reporting details of their studies to reduce concerns regarding their study bias.

Anaesthetic Efficacy of 4% Articaine in Comparison with 2% Lidocaine as Intraligamentary Injections after an Ineffective Inferior Alveolar Nerve Block in Mandibular Molars with Irreversible Pulpitis: A Prospective Randomised Triple-Blind Clinical Trial

The objective of the current study was to compare the anaesthetic efficacy of supplemental intraligamentary (IL) injection of 4% articaine with that of 2% lidocaine in the mandibular first and second molars with irreversible pulpitis after an ineffective inferior alveolar nerve block injection (IANB) using the same anaesthetic in a randomised triple-blind clinical trial. Seventy-six adult patients, who were diagnosed with irreversible pulpitis in the mandibular first or second molars, were divided into 2 groups and received IANB randomly. In patients with lip numbness, anaesthesia was evaluated with the cold and electrical pulp (EPT) tests, and if the reported number on EPT was below 100, supplemental IL injection was administered using the same anaesthetic. The teeth were retested after 5 minutes. The Heft-Parker visual analogue scale was used to evaluate pain after IANB and IL injections. Statistical analysis was performed using repeated measures ANOVA, chi-square, and independent-sample and paired-sample t-tests. The results showed that there was no significant difference in the success rates of supplemental IL and IANB injections between articaine and lidocaine. Furthermore, there was no significant difference in the success rates of supplemental IL injection with lidocaine between the mandibular first and second molars. However, there was a significant difference in the success rates of supplemental IL injection with articaine between the mandibular first and second molars. Moreover, supplemental IL injections indicated no significant difference in the anaesthetic efficacy between articaine and lidocaine; nevertheless, they were more effective in the mandibular second molars, especially with articaine.

Comparing the Efficacy of Twin Mix and Lidocaine for Inferior Alveolar Nerve Blocks in Patients With Symptomatic Irreversible Pulpitis

This randomized, active-controlled, double-blind, prospective clinical trial evaluated the anesthetic efficacy of 2% lidocaine with 1:200,000 epinephrine versus an admixture of 2% lidocaine with 1:200,000 epinephrine and 1 mL of 4 mg dexamethasone (Twin mix) for inferior alveolar nerve blocks (IANBs) in patients with symptomatic irreversible pulpitis (SIP) of the mandibular molars. Seventy-eight patients with SIP of mandibular molars were randomly allocated to the 2 groups of 39 subjects. All patients were required to have profound lip numbness within 10 minutes of local anesthetic deposition. The efficacy of pulpal anesthesia was confirmed by absence of pain or mild pain (Heft-Parker visual analogue scale ≤54 mm) during access cavity preparation and placement of glide path files. The collected data were subjected to independent t test, chi-square test, and Fisher exact test using SPSS software version 20.0 at a significance level of 0.05. IANB success rates for the lidocaine group and the Twin mix group was 66% and 68% respectively, which was not a statistically significant difference (p > .05). This study demonstrated that the anesthetic efficacy of Twin mix was equivalent to 2% lidocaine for IANBs in teeth with SIP.

Effect of relative head position on the anesthetic efficacy of inferior alveolar nerve block during endodontic treatment of patients with irreversible pulpitis

Background

The purpose of this prospective randomized single-blind clinical trial was to evaluate the effect of tilting the head on the anesthetic efficacy of inferior alveolar nerve block (IANB) in patients with symptomatic irreversible pulpitis.

Methods

Ninety-two patients were divided into two groups: the first group received IANB and the head was tilted in the direction of the block for 15 min, whereas the second group received IANB and the head was tilted to the opposite side. Access cavity preparation was initiated after 15 min. Success was defined as no pain or faint/weak/mild pain during endodontic access preparation and instrumentation. The anesthetic success rates were analyzed by Pearson chi-square test at 5% significance levels.

Results

The same side position and opposite side position yielded 41% and 30% anesthetic success rates, respectively; there was no significant difference between the two sides.

Conclusions

Relative head position has no effect on the anesthetic success rate of IANB.

Effective anaesthesia of the acutely inflamed pulp: part 2. Clinical strategies

Achieving profound pulpal anaesthesia in a mandibular molar diagnosed with irreversible pulpitis can be argued to be the most testing of dental anaesthetic challenges. Following discussion on the possible reasons for this occurrence in part 1, part 2 outlines the various local anaesthetic techniques that practitioners can use to overcome the acutely inflamed mandibular molar. They should then be able to apply these same principles to help anaesthetise any other tooth presenting with an acutely inflamed pulp. Techniques are discussed in detail along with key variables that have been associated with having an impact on the anaesthetic efficacy. This is to bring to light factors that can aid anaesthetic success as well as dispel common misnomers.

The success rate of bupivacaine and lidocaine as anesthetic agents in inferior alveolar nerve block in teeth with irreversible pulpitis without spontaneous pain

Objectives

Achieving adequate anesthesia with inferior alveolar nerve blocks (IANB) is of great importance during dental procedures. The aim of the present study was to assess the success rate of two anesthetic agents (bupivacaine and lidocaine) for IANB when treating teeth with irreversible pulpitis.

Materials and Methods

Sixty volunteer male and female patients who required root canal treatment of a mandibular molar due to caries participated in the present study. The inclusion criteria included prolonged pain to thermal stimulus but no spontaneous pain. The patients were randomly allocated to receive either 2% lidocaine with 1:80,000 epinephrine or 0.5% bupivacaine with 1:200,000 epinephrine as an IANB injection. The sensitivity of the teeth to a cold test as well as the amount of pain during access cavity preparation and root canal instrumentation were recorded. Results were statistically analyzed with the Chi-Square and Fischer's exact tests.

Results

At the final step, fifty-nine patients were included in the study. The success rate for bupivacaine and lidocaine groups were 20.0% and 24.1%, respectively. There was no significant difference between the two groups at any stage of the treatment procedure.

Conclusions

There was no difference in success rates of anesthesia when bupivacaine and lidocaine were used for IANB injections to treat mandibular molar teeth with irreversible pulpitis. Neither agent was able to completely anesthetize the teeth effectively. Therefore, practitioners should be prepared to administer supplemental anesthesia to overcome pain during root canal treatment.

Does the combination of 3% mepivacaine plain plus 2% lidocaine with epinephrine improve anesthesia and reduce the pain of anesthetic injection for the inferior alveolar nerve block? A prospective, randomized, double-blind study

INTRODUCTION

In theory, using 3% mepivacaine initially for an inferior alveolar nerve (IAN) block would decrease the pain of injection, provide faster onset, and increase anesthetic success. The purpose of this prospective, randomized, double-blind study was to compare the degree of pulpal anesthesia obtained with a combination of 3% mepivacaine/2% lidocaine (1:100,000 epinephrine) versus a combination of 2% lidocaine (1:100,000 epinephrine)/2% lidocaine (1:100,000 epinephrine) in IAN blocks. Injection pain was also studied.

METHODS

One hundred asymptomatic subjects were randomly given a combination of a 1-cartridge volume of 3% mepivacaine plus a 1-cartridge volume of 2% lidocaine with 1:100,000 epinephrine and a combination of a 1-cartridge volume of 2% lidocaine with 1:100,000 epinephrine plus a 1-cartridge volume of 2% lidocaine with 1:100,000 epinephrine for the IAN block at 2 separate appointments. Subjects rated the pain of injection. The molars, premolars, and incisors were tested with an electric pulp tester in 4-minute cycles for 60 minutes. Anesthetic success was defined as the subject achieving 2 consecutive 80 readings within 15 minutes after completion of the IAN blocks and sustaining the 80 reading for 60 minutes.

RESULTS

Success was not significantly different (P > .05) between the 2 combinations. No statistical differences in injection pain or onset times were found.

CONCLUSIONS

The combination of 3% mepivacaine plus 2% lidocaine with 1:100,000 epinephrine was equivalent to the combination of 2 cartridges of 2% lidocaine with 1:100,000 epinephrine in terms of injection pain, onset time, and pulpal anesthetic success for the IAN block.

Efficacy of supplementary buccal infiltrations and intraligamentary injections to inferior alveolar nerve blocks in mandibular first molars with asymptomatic irreversible pulpitis: a randomized controlled trial

AIM

This randomized double-blinded controlled trial was performed to compare the efficacy of inferior alveolar nerve block (IANB) injection for mandibular first molar teeth with irreversible pulpitis with or without supplementary buccal infiltration and intraligamentary injection.

METHODOLOGY

Eighty-two patients with asymptomatic irreversible pulpitis received either a combination of intraligamentary injection + buccal infiltration+ IANB or with traditional IANB injection in mandibular first molar teeth with irreversible pulpitis. Each patient recorded their pain score on a Heft-Parker visual analogue scale before commencing treatment, in response to a cold test 15 min after the designated anaesthetic injection, during access cavity preparation and during root canal instrumentation. No or mild pain at any stage was considered a success. Data were analysed by chi-square test.

RESULTS

At the final stage of treatment, 69 of the 82 patients were eligible to be included in the study. No significant difference was found between age (P = 0.569) and gender (P = 0.570) amongst the patients in the two groups. The success rate of anaesthesia in the IANB and the combination groups were 22% and 58%, respectively. The success rate of anaesthesia in the combination group was significantly higher than the traditional IANB injection (P = 0.003).

CONCLUSION

A combination of anaesthetic techniques can improve the success rate of anaesthesia for mandibular first molar teeth with irreversible pulpitis.