Success Of Inferior Alveolar Nerve Block Research Articles

Intracranial Air Embolism after Inferior Alveolar Nerve Block: A Case Report.

IntroductionThe number of nontraumatic dental pain emergency department (ED) visits continues to substantially rise in frequency every year. While there are several methods for treating dental pain, an inferior alveolar nerve block (IANB) is a non-narcotic alternative that provides instantaneous relief of severe pain.Case ReportA 59-year-old male presented to the ED from a dentist’s office for evaluation of a right-sided headache with an associated episode of palpitations and near syncope that developed while receiving an inferior alveolar nerve block. Computed tomography of the patient’s head revealed multiple small foci of air in the right temporalis muscle and in the intracranial venous drainage system. Given the patient’s history of dental procedure, the intravascular introduction of air and local anesthetic was suspected.ConclusionInferior alveolar nerve block procedures can have complications, including hematoma formation, trismus, facial palsy, needle breakage, and in this case, intravascular injection and cerebral air embolism. To perform a successful IANB, it is critical for providers to be familiar with anatomical landmarks and to consistently perform aspiration to confirm that needle placement is not intravascular.

The effect of inferior alveolar nerve block anesthesia of 4% articaine and epinephrine 1:100,000 on blood flow and anesthesia of human mandibular teeth

Background/purposeLocal anesthetics and anesthetic techniques affect the patterns of pulpal blood flow (PBF) and pulpal anesthesia in human teeth. This study aimed to determine PBF changes and pulpal anesthesia of intact mandibular first molars and canines after administration of 4% articaine with epinephrine 1:100,000 using inferior alveolar nerve block (IANB). Materials and methodsTen healthy subjects received IANB of 4% articaine with epinephrine 1:100,000. Laser Doppler flowmetry and electrical pulp testing were combined to assess PBF changes and pulpal anesthesia of intact mandibular first molars and canines. The data were analyzed using one-way repeated-measures analysis of variance and Student–Newman–Keuls test. ResultsIANB with 4% articaine and epinephrine 1:100,000 did not have any significant change in PBF for the first 20 min post injection in mandibular first molars, and for 45 min post injection in the canines (P > 0.05). However, a hyperemic response occurred during 25–60 min post injection in the molars, and between 60 and 75 min post injection in the canines (P < 0.05). Thereafter, the PBF in both teeth returned to the baseline. Onset of pulpal anesthesia was 8.60 ± 2.12 min in the molars, and 9 ± 1.94 min in the canines. Duration of pulpal anesthesia was 82.40 ± 41.56 min in the molars, and 84 ± 47.40 min in the canines. ConclusionIn case of successful IANB, 4% articaine and epinephrine 1:100,000 caused insignificant changes in PBF up to 30 min but a hyperemic response at later time points. Thereafter, the PBF returned to the baseline.

Efficacy of submucosal tramadol and lidocaine on success rate of inferior alveolar nerve block in mandibular molars with symptomatic irreversible pulpitis.

The aim of the present study is to compare the efficacy of additional 100mg/2ml tramadol and 40mg/2ml lidocaine applications on the anesthetic success of inferior alveolar nerve block (IANB) in mandibular molars with symptomatic irreversible pulpitis (MM-SIP). One hundred and five patients diagnosed with symptomatic pulpitis in the lower first or second molars were included in the study. Patients were randomly divided into three groups (n = 35) composed of control and two experimental groups administered submucosal tramadol and lidocaine. Preoperative pain levels of the patients were measured with Heft-Parker visual analog scale (HP VAS). Following, standard IANB with 2% lidocaine 1: 80,000 was administrated to all groups. After observation of lip numbness, 2ml of saline in the control group, 100mg/2ml tramadol in tramadol group and 40mg/2ml (2%, 1: 80,000) lidocaine in lidocaine group were administered submucosally. After 15min, standard endodontic treatment was initiated and the pain levels measured from access cavity preparation to pulp extirpation were measured with HP VAS. The success rate of pulpal anesthesia was 28.5% in the control group, 45.7% in the submucosal lidocaine group and 48.6% in the tramadol group. There was no statistically significant difference in the success rate between the groups. Additional submucosal administration of 100mg tramadol did not significantly increase the success of IANB applied with a combination of 2% lidocaine 1:80,000 and epinephrine in MM-SIP compared to control group.

Effect of magnesium sulphate added to lidocaine on inferior alveolar nerve block success in patients with symptoms of irreversible pulpitis: a prospective, randomized clinical trial.

To investigate the effect of magnesium sulphate used as an adjuvant to lidocaine with epinephrine local anaesthetic on the success of inferior alveolar nerve blocks (IANB) in patients with symptoms of irreversible pulpitis undergoing root canal treatment. In a double-blind clinical trial, following power calculation, 124 patients with symptoms of irreversible pulpitis in mandibular molar teeth were selected, and initial pain data were collected using a Heft-Parker (Pain, 19, 1984 and 153) visual analogue scale. The first group (control) received IANB with 1.8 mL of a local anaesthetic solution containing 1.8% lidocaine with 1:88000 epinephrine while the second group (test) received IANB with 1.8 mL of an anaesthetic solution containing 1% magnesium sulphate, and 1.8% lidocaine with 1:88000 epinephrine. Pain data were collected after access cavity and penetration of files in the canals using a Heft-Parker visual analogue scale. Two patients were not included in the study as they did not consent, and a further 54 patients were excluded as they did not report lip numbness within 15min after IANB administration; thus, the data presented in this study are related to 68 patients. The data were analysed using chi-square and t-test (α=0.05). The success of pulpal anaesthesia with IANB was 82% for the magnesium sulphate group and 53% for the control group. There was a significant difference in the effectiveness of the IANB between the two groups (P<0.001). There was no significant difference between the magnesium sulphate and control groups regarding gender (P=0.598) or age (P=0.208) or initial pain scores (P=0.431). The addition of 1% magnesium sulphate to 1.8% lidocaine with 1:88000 epinephrine resulted in a positive impact for the success of IANB in patients with a diagnosis of irreversible pulpitis related to mandibular molar teeth undergoing root canal treatment. Thus magnesium sulphate may be used as adjuvant for achieving profound pulpal anaesthesia in challenging cases. However, more studies with larger sample size and different concentration doses must be carried out to establish an appropriate conclusion before its routine clinical use.

Anesthetic efficacy of articaine/epinephrine plus mannitol in comparison with articaine/epinephrine anesthesia for inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: A randomized controlled clinical trial.

Background. It is difficult to achieve successful pulpal anesthesia in mandibular posterior teeth with symptomatic irreversible pulpitis. The present study aimed to compare the effect of articaine/epinephrine anesthesia with articaine/epinephrine at a combination of 0.5 mol/mL of mannitol for the inferior alveolar nerve block (IANB) in patients presenting with symptomatic irreversible pulpitis in the mandibular first molar tooth. Methods. One hundred patients with symptomatic irreversible pulpitis in the mandibular first molar tooth were selected and randomly divided into two groups based on the injection method. The first group underwent an IANB technique with 1.8 mL of articaine, whereas the second group received 2.9 mL of a formulation, consisting of 1.8 mL of articaine plus 1.1 mL of 0.5 mol/L of mannitol. Fifteen minutes after injections and anesthesia of the lip, the access cavity was prepared. According to the visual analog scale (VAS) criteria, no pain or mild pain for caries removal, pulp exposure and canal instrumentation were regarded as success. Chi-squared test was used for the analysis of data. The level of significance was set at 0.05. Results. The success rate in the group with articaine/epinephrine anesthesia plus mannitol was higher than that in the group with articaine/epinephrine anesthesia, with no significant difference between the two groups (P>0.05). Conclusion. It was concluded, under the limitations of this study, that adding mannitol to articaine/epinephrine anesthesia did not increase the success of IANB in mandibular posterior teeth with symptomatic irreversible pulpitis.

Prevalence of Failed Inferior Alveolar Nerve Block (IANB) in Achieving Pulpal Anaesthesia in Mandibular Molars with Symptomatic Irreversible Pulpitis

Introduction: Patient comfort during root canal treatment is immense for patient cooperation and endodontist efficiency. Establishing the high prevalence of failure of IANB injections in providing pulpal anaesthesia, will most likely support the investigation of supplemental techniques to ensure patient comfort. Objectives: The study aimed to evaluate the prevalence of failed Inferior Alveolar Nerve Block (IANB) injections in achieving pulpal anaesthesia in mandibular molars diagnosed with symptomatic irreversible pulpitis when administered alone. Methods: This study involved fifty patients, diagnosed with symptomatic irreversible pulpitis in their mandibular first and second molars. IANB injection using 2% lidocaine with 1:100,000 epinephrine was administered to anesthetize the acutely inflamed teeth before commencing root canal treatment. Lip and tongue numbness was checked subjectively after injection to ensure successful IANB injection. Objectively, cold test was performed after 15 minutes and pain level was recorded using Visual Analogue Scale (VAS). Success was defined as no pain response by (VAS) during cavity preparation, endodontic access, or initial instrumentation. Results: Although, majority of patient (96%) expressed surrounding soft tissue numbness, only 73% did not feel any pain during initiating root canal treatment. Conclusions: IANB injection alone is not enough to provide profound pulpal anaesthesia in acutely inflamed mandibular molars; therefore, supplemental injections are required to achieve patients comfort during treatment.

Measurement of mandibular lingula location using cone-beam computed tomography and internal oblique ridge-guided inferior alveolar nerve block.

ObjectivesInferior alveolar nerve block (IANB) is the most frequently used treatment for mandibular molars. Successful IANB requires insertion of the dental needle near the mandibular foramen. In this study, we aimed to analyze the anatomic location of the mandibular lingula and evaluate the effects of internal oblique ridge (IOR)-guided IANB.Materials and MethodsThe location of the mandibular lingula was measured using cone-beam computed tomography images of the mandibles obtained from 125 patients. We measured the distances from the occlusal plane to the lingula and from the IOR to the lingula in 250 mandibular rami. Based on the mean of these distances, alternative anesthesia was carried out on 300 patients, and the success rate of the technique was evaluated.ResultsThe mean vertical distance was 8.85±2.59 mm, and the mean horizontal distance was 14.68±1.44 mm. The vertical (P<0.001) and the horizontal (P<0.05) distances showed significant differences between the sex groups. The success rate of the IOR-guided technique was 97.3%.ConclusionIANB-based location of mandibular lingula showed a high success rate. From this study, we concluded that analysis of the anatomic locations for mandibular lingula and IOR-guided IANB are useful for restorative and surgical dental procedures of the mandibular molars.

Anatomy of successful inferior alveolar nerve block

Anatomy of successful inferior alveolar nerve block

Oral Ketorolac with Inferior Alveolar Nerve Block for Irreversible Pulpitis: A Systematic Review and Meta-analysis.

Background:Ketorolac has advantages over other analgesics as a pre-anaesthetic medication. Considering this in mind, the present meta-analysis aims to identify the effect of oral ketorolac premedication on the anaesthetic efficacy of Inferior Alveolar Nerve Block (IANB) in patients with irreversible pulpitis.Methods:Full-texts of eligible studies were obtained from electronic databases. The extracted data was analysed using non-Cochrane mode in RevMan 5.0 software. Relative risk [95% CI] was calculated for the success of IANB.Results:Four studies were included for the final review. The success rate of IANB on 221 patients with relative risk of 1.87 [1.36, 2.56] was statistically significant favouring ketorolac. The mean difference for VAS in 171 patients was not statistically significant {-13.55 [-33.91, 6.82]}.Conclusion:Oral ketorolac can be successfully administered as a premedication before conventional inferior alveolar nerve block for endodontic treatment for irreversible pulpitis.

Effect of oral premedication on the anaesthetic efficacy of inferior alveolar nerve block in patients with irreversible pulpitis - A systematic review and network meta-analysis of randomized controlled trials.

This systematic review (SR; PROSPERO database: CRD42017075160) and network meta-analysis (NMA) identified the most effective oral premedication for anaesthetic success of inferior alveolar nerve blocks (IANB) in cases of irreversible pulpitis. Medline and Ebscohost databases were searched up until 10/2017. Randomized controlled trials (RCT) studying the effect of oral premedication, alone or in combination, on the success of IANB for cases of irreversible pulpitis, compared to placebo or other oral premedications, were included. Quality of the included studies was appraised by the revised Cochrane risk of bias tool for randomized trials. Pairwise analysis, NMA and quality of evidence assessment using GRADE criteria were performed. Nineteen studies (n=1654 participants) were included. NMA demonstrated that compared to placebo, dexamethasone was most effective in increasing anaesthetic success (RR, 2.92 [95% CI 1.74,4.91]; SUCRA=0.96), followed by NSAIDs (RR, 1.92 [95% CI 1.63,2.27], SUCRA=0.738) and Tramadol (RR, 2.03 [95% CI 1.18,3.49], SUCRA=0.737). Premedication with acetaminophen added to NSAIDs demonstrated similar efficacy as NSAIDs alone (RR, 1.06 [95% CI 0.79,1.43]). Sensitivity analyses proved the superiority of dexamethasone or NSAIDs over any other premedications. Subgroup analyses of specific dosages in comparison with placebo demonstrated that dexamethasone 0.5mg was most effective, followed by ketorolac 10mg, piroxicam 20mg, ibuprofen 400mg+ acetaminophen 500mg and Tramadol 50mg. Ibuprofen 400mg, 600mg and 800mg had a significantly improved IANB success, while Ibuprofen 300mg had no effect. Oral premedication with dexamethasone, NSAIDs or Tramadol significantly increased anaesthetic success. More trials are needed to evaluate the premedication effects of dexamethasone or Tramadol for improved anaesthetic success of IANB when treating irreversible pulpitis.

Efficacy of Articaine versus Lidocaine in Supplemental Infiltration for Mandibular First versus Second Molars with Irreversible Pulpitis: A Prospective, Randomized, Double-blind Clinical Trial

IntroductionProfound pulpal anesthesia is difficult to achieve in mandibular molars with irreversible pulpitis (IP). However, there are no published randomized controlled clinical trials comparing the success of supplemental buccal infiltration (BI) in mandibular first versus second molars with IP. The purpose of this prospective, randomized, double-blind study was to compare the efficacy of 4% articaine with 2% lidocaine for supplemental BIs in mandibular first versus second molars with IP after a failed inferior alveolar nerve block (IANB). This study's sample was combined with data from a previous trial. MethodsOne hundred ninety-nine emergency subjects diagnosed with IP of a mandibular molar were selected and received an IANB with 4% articaine. Subjects who failed to achieve profound pulpal anesthesia, determined by a positive response to cold or pain upon access, randomly received 4% articaine or 2% lidocaine as a supplemental BI. Endodontic access was begun 5 minutes after infiltration. Success was defined as less than mild pain during endodontic access and instrumentation on the Heft-Parker visual analog scale. ResultsThere was a 25% IANB success rate with 4% articaine. The success rate for articaine supplemental BI in first molars was 61% versus 63% for second molars (P > .05). The success of lidocaine in first molars was 66%, but for second molars it was 32% (P = .004). ConclusionsThe success rate for IANB with 4% articaine was 25%. Articaine and lidocaine had similar success rates for supplemental infiltration in first molars, whereas articaine was significantly more successful for second molars. However, because BI often did not provide profound pulpal anesthesia, additional techniques including intraosseous anesthesia may still be required.

The effect of preoperative submucosal administration of tramadol on the success rate of inferior alveolar nerve block on mandibular molars with symptomatic irreversible pulpitis: a randomized, double-blind placebo-controlled clinical trial.

This randomized, double-blind, placebo-controlled, clinical trial was designed to improve the success of inferior alveolar nerve blocks (IANB) in mandibular molars with symptomatic irreversible pulpitis (SIP) by means of preoperative submucosal administration of 50mg tramadol. Forty-two patients with a mandibular molar diagnosed with SIP took part in the trial. Patients were assigned randomly to one of two groups: tramadol group (n=21), who received 50mg tramadol in 1mL by mandibular infiltration, and a placebo group (n=21), who received 1mL of normal saline administered to the affected tooth by the same means. Ten minutes later, all patients received an IANB with 4% articaine with epinephrine 1:100 000. A 10-min waiting time was established after local anaesthetic (LA) administration before carrying out three consecutive tests to assess anaesthesia of the pulp, that is two consecutive negative responses to an electric pulp test, positive or negative response to a cold test and no pain during access cavity preparation. IANB was considered successful only if the patient did not experience pain arising from these tests. Data were analysed by the Chi-squared frequency test and the Fisher's exact test, for qualitative variables, Mann-Whitney U-test for independent samples and two-way anova for more than two independent samples. In the tramadol group IANB was achieved successfully in 57% of the sample, whilst the placebo group obtained 29%. The difference between groups was not significant (P=0.06). When performing endodontic access, the anaesthetic success rate was significantly in favour of tramadol (P=0.03). Preoperative submucosal administration of 50mg tramadol in mandibular molars with SIP significantly improved the success of IANB using 4% articaine with 1:100000 epinephrine during access cavity preparation in comparison with a placebo.

Successful pulpal anesthesia for symptomatic irreversible pulpitis

Background and OverviewProfound pulpal anesthesia after a successful inferior alveolar nerve block can be difficult to achieve when the clinical condition is a pulpal diagnosis of symptomatic irreversible pulpitis. The authors reviewed the literature as it relates to the anesthesia necessary for endodontic therapy of patients with painful, vital, mandibular teeth diagnosed with symptomatic irreversible pulpitis. ConclusionsSupplemental anesthetic techniques and medications are available that can be used to improve pulpal anesthesia for patients with the clinical condition of symptomatic irreversible pulpitis. Practical ImplicationsThe authors identified treatment recommendations for anesthesia in the case of symptomatic irreversible pulpitis based on a review of the available evidence.

Inferior alveolar nerve block for the treatment of teeth presenting with irreversible pulpitis: A systematic review of the literature and meta-analysis.

The objective of the present systematic review was to evaluate, in patients with irreversible pulpitis affecting mandibular posterior teeth, if premedication with nonsteroidal anti-inflammatory drugs can increase the efficacy of inferior alveolar nerve block (IANB) if compared to placebo administration; if one anesthetic agent is more effective than another; if 1.8 mL injection is more effective than 3.6 mL injection to increase the efficacy of IANB; and if supplementary buccal injection is able to increase the efficacy of IANB as compared to a negative control/placebo group. Randomized controlled clinical trials investigating different aspects (technique, premedication with anti-inflammatory drugs, different anesthetic agents) were searched. Success of IANB, as defined in the studies, was considered as the primary outcome. A meta-analysis was performed evaluating relative risks (RRs). Electronic databases (Medline, Embase, Cochrane Central) were searched after preparation of an appropriate search string. After application of selection criteria, a total of 37 studies were included; 19 of them were considered in the meta-analysis. There was evidence of a difference in favor of the use of premedication with anti-inflammatory drugs (RR, 1.80; CI 95%, 1.50-2.14; P < .0001). There was no evidence of a difference between articaine and lidocaine (RR, 1.05; CI 95%, 0.91-1.21; P = .94). With regard to the volume of anesthetic infiltrated, the computed RR was 1.17 (CI, 0.73-1.88) without any significant difference between the use of one or two cartridges (P = .52). The estimated RR for a supplementary buccal infiltration was 1.56 (CI, 1.00-2.42; P = .05). The use of premedication with anti-inflammatory drugs before IANB can increase the efficacy of the IANB. The type of anesthetic agent, the volume of anesthetic, and the use of a supplemental buccal infiltration do not seem to affect the efficacy of anesthesia.

Buffered Lidocaine With Sodium Bicarbonate did not Increase Inferior Alveolar Nerve Block Success Rate in Patients Having Symptomatic Irreversible Pulpitis

Effect of buffered 4% lidocaine on the success of the inferior alveolar nerve block in patients with symptomatic irreversible pulpitis: a prospective, randomized, double-blind study. Schellenberg J, Drum M, Reader A, Nusstein J, Fowler S, Beck M. J Endod 2015;41(6):791-6. The study was supported by Meyers/Reader Graduate Endodontic Support Fund Double blinded randomized controlled trial.

Study of surgical landmarks of mandibular foramen for inferior alveolar nerve block: An Osteological study

Background: Local Anaesthesia to inferior alveolar nerve is one of the most common procedures done by surgeons for various treatments and to make it more effective the anaesthetic agent has to be infiltrated closer to mandibular foramen. Unluckily the success rate of inferior alveolar nerve block is very less due to inaccurate localization of the mandibular foramen leading to improper placement of the needle. Objective: The present study has been carried out on dry mandibles to determine the accurate position of mandibular foramen from various landmarks of mandible to provide with the suitable data to help the surgeons to locate the Mandibular foramen with more precision for successful Inferior Alveolar Nerve block. Materials and Methods: This study was carried out in department of anatomy, Yenepoya medical college. A total of 100 dry mandibles were studied on its both sides to locate the mandibular foramen using digital Vernier calipers. Results: The Mean and standard deviation values on right and left sides of the mandibles to locate the mandibular foramen from its anterior border are 17.69(±2.70), 17.94(±2.73), posterior border 11.39(±1.93), 11.40(±2.01), Mandibular notch 22.90(±3.57), 22.39(±3.18), angle of Mandible 23.87(±4.52), 23.66(±4.36) and 3M-third molar to mandibular foramen 17.9(±3.57), 17.6(±3.77) respectively. Conclusion: The comprehension of the Mandibular foramen is of a considerable importance for inferior alveolar nerve anesthesia, dento alveolar surgeries, endodontic treatments and lesions diagnosis. Its precise location enables a more effective anesthesia. Incorrect estimations of its location might be the reason for the unsuccessful anesthesia of the inferior alveolar nerve and damage of neurovascular structures passing through it. Keywords: Local anaesthesia, Inferior alveolar nerve, Mandibular foramen, localization, dentoalveolar surgeries

Effect of Local and Application of Amitriptyline and Imipramine on Teeth with Irreversible Pulpitis Failed Pulpal Anesthesia: A Randomized, Double-blind, Controlled Trial

Introduction: To evaluate the analgesic effect of amitriptyline and imipramine after local application on the dentine of “hot teeth” with failed pulpal anesthesia. Materials and Methods: This study was a randomized, double-blind clinical trial that was performed on 33 consenting adult patients who were referred to us and had mandibular molars diagnosed with symptomatic irreversible pulpitis and experienced pain during access cavity preparation after receiving successful inferior alveolar nerve block with lidocaine. Either amitriptyline, imipramine or placebo was administered locally on the exposed dentine of the teeth. Pre and post-application pain levels were evaluated by McGill visual analog scale. Results: Amitriptyline significantly reduced the pain experienced by patients (P = 0.032). Imipramine also reduced the experienced pain but the pain relief was not statistically significant when compared with the placebo. Conclusion: Local administration of amitriptyline on exposed dentine can reduce the pain experienced by patients with a “hot tooth.”

Changes in the location of the human mandibular foramen as a function of growth and vertical facial type

Objective. A previous cross-sectional investigation showed that the mandibular foramen location depends on the age and the vertical facial pattern of growing individuals. The aim of the present longitudinal study was to explain how these factors influence the distance between the foramen and the occlusal plane. It is known that a certain distance is necessary for a successful inferior alveolar nerve block in clinical dentistry. Materials and methods. This distance, as well as another four cephalometric variables, were measured on both pre-treatment and 10-year post-treatment lateral cephalometric radiographs collected from 50 patients who underwent orthodontic treatment. The changes between these two sets of measurements were also calculated. Results. A multiple regression analysis was performed using the pre-treatment age, the pre-treatment inter-maxillary angle, the rotation of the occlusal plane and the change in mandibular ramus height as independent variables and the change of foramen-occlusal plane distance as a dependent variable. The independent variables under investigation were found to account for more than half of the variability of the foramen-occlusal plane distance (r = 0.732; p < 0.001). Conclusion. In very young individuals the mandibular foramen is located approximately at the level of the occlusal plane. With age it moves upwards relative to the occlusal plane and more so for those individuals with a low anterior facial height (short-face vertical facial type). These observations are, at least, partially explained by the differential growth of the various elements of the maxillo-mandibular complex and the change of the inclination of the occlusal plane.

Arched Needle Technique for Inferior Alveolar Mandibular Nerve Block

Although, needle breakage remains a rare complication during oral local anesthesia (LA) administration, there are ample reports mandating a careful technique and precautionary measures to prevent this complication [1–4]. Chakranarayan and Mukherjee [5] describe a method of inferior alveolar nerve block (IANB) by injecting a local anesthetic solution into the pterygomandibular space by arching the needle and changing the approach angle of the conventional technique. The authors describe arching the needle after the initial insertion and inserting it in a manner that it approaches the medial surface of the ramus at an angle almost perpendicular to it. Although Chakranarayan and Mukherjee highlight in their study that bending the needle was found safe in their study patients, advocating bending an advancing needle within the oral tissues may not be a safe surgical practice. The incidence of needle breakage is such a rare occurrence that studying a small group of patients can not endorse the safety of a technique. Pogrel has estimated the risk of needle breakage amongst Northern California dentists at 1 in 14 million inferior alveolar nerve blocks [2, 8]. If the needle was checked in vitro before using them in patients in their study [5], by theory, this practice further weakens the needle due to undue stress and strains on its material before use. In a review of cases by Malamed et al. [8] intentional bending of the needle by the doctor before injection is reported to be an important factor for needle breakage. The very concept of inferior alveolar nerve block is to deposit the solution in the pterygomandibular space. Depositing the solution near the mandibular foramen may have an advantage of an early onset of LA, but in this case it is at the cost of potential risk of needle breakage. It should be noted that IANB remains the most susceptible technique to have an incidence of a needle breakage. It is not a common occurrence, but when it occurs it may be a detrimental event both for the patient and the treating dental surgeon. The rare incidence of needle breakage will mandate a high radiation imaging study to localize the needle and a surgical exploration under general anesthesia for its retrieval [2]. Okamoto et al. [6, 7] studied the spread of local anesthetic solution in the inferior alveolar nerve block and found that local anesthetic solution spreads and rapidly fills nearly the entire pterygomandibular space by completion of the injection, emphasizing the fact that targeting the mandibular foramen to deposit the solution may not be necessary for the success of IANB.

Effect of Premedication with Ibuprofen and Dexamethasone on Success Rate of Inferior Alveolar Nerve Block for Teeth with Asymptomatic Irreversible Pulpitis: A Randomized Clinical Trial

IntroductionThe aim of this study was to compare 2 kinds of anti-inflammatory medicines (ie, dexamethasone and ibuprofen) with a placebo according to their effects on the success rates of an inferior alveolar nerve block (IANB) for the endodontic treatment of mandibular molars with irreversible pulpitis. MethodsA total of 165 patients were divided into 3 groups of 55 patients each and were given a capsule of the same color and size (ie, a placebo of lactose powder, 400 mg ibuprofen, or 0.5 mg dexamethasone). One hour after the oral administration of the capsules, all the patients received a standard IANB. In patients with a successful IANB, the teeth were examined with a cold pulp test. Patients were asked to assess their pain using the visual analog scale. Then, endodontic access cavity preparation was initiated. In case of pain during the treatment, the patients were asked to rate the pain on the visual analog scale. Success was defined as no or mild pain during treatment. The chi-square test and analysis of variance were used to compare qualitative and quantitative data among the groups. ResultsNo significant differences were found regarding the sex of the patients in the 3 groups (P > .05). The dexamethasone group showed significantly higher success rates compared with the placebo group (P = .001). There were no significant differences between the ibuprofen and placebo groups (P = .055) or the dexamethasone and ibuprofen groups (P = .34). ConclusionsPremedication with dexamethasone increased the success rate of an IANB in mandibular molars with asymptomatic irreversible pulpitis.