Buccal infiltration versus inferior alveolar nerve block in mandibular 2nd premolars with irreversible pulpitis.

PURPOSE: The purpose of this study is to compare the success rates of inferior alveolar nerve block (IANB) and buccal infiltration anesthesia of mandibular second premolar with irreversible pulpitis and to evaluate the level of patient discomfort with these methods. MATHERIALS AND METHODS: Forty patients, who had irreversible pulpitis in the mandibular 2nd premolar teeth, were included in the study. Patients were randomly distributed in two groups. In one group IANB, in the other group buccal infiltration anesthesia were performed. The efficacy of these two different anesthesia techniques on the related teeth was investigated with the Heft-Parker visual analog scale. In addition, with a pulse oximetry device, the changes in the patients' heart rates were compared between the groups. The obtained data were evaluated statistically. RESULTS: Both anesthesia techniques reduced the pain significantly in patients before the administration (P < 0.05), but there was no significant difference among the groups regarding the pain control and success rates of anesthesia (P > 0.05). Both of the anesthesia techniques increased the heart rate (P < 0.05). The increase in the heart rate of the patients was significantly higher in the buccal infiltration anesthesia group than the other anesthesia group (P < 0.05). CONCLUSION: Within the limitation of this in vivo study, there was no difference between the efficacies of the buccal infiltration anesthesia and IANB anesthesia in the mandibular 2nd premolar teeth with irreversible pulpitis. Buccal infiltration anesthesia caused more discomfort in the patients compared with the IANB during the administration.

Efficacy of Ketorolac Buccal Infiltrations and Inferior Alveolar Nerve Blocks in Patients with Irreversible Pulpitis: A Prospective, Double-blind, Randomized Clinical Trial.

INTRODUCTION: The purpose of this prospective, randomized, double-blind, placebo-controlled study was to determine whether ketorolac buccal infiltrations (BIs) helped to improve the success of inferior alveolar nerve blocks (IANBs) in patients with acute irreversible pulpitis (AIP). METHODS: Forty adult volunteers with AIP in a mandibular molar were included in this study. Patients were instructed to evaluate their pain by using a Heft-Parker visual analog scale. They were randomly divided into 2 groups (n = 20). All patients received standard IANB injection and after that a BI of 4% articaine with 1:100,000 epinephrine. After 5 minutes, 20 patients received a BI of 30 mg/mL ketorolac, and the other received a BI of normal saline (control group). Endodontic access cavity preparation (ACP) was initiated 15 minutes after the IANB when the patient reported lip numbness and had 2 electric pulp tests with no responses. The patient's pain during caries and dentin removal, ACP, and canal length measurements (CLM) was recorded by using Heft-Parker visual analog scale. Successful anesthesia was defined as no or mild pain during any of these steps, without the need for additional injection. Data were statistically analyzed by using Mann-Whitney U and χ(2) tests. RESULTS: Successful anesthesia after an IANB plus BI of articaine was obtained in 15% of patients in the control group at the end of CLM. Adding BI of ketorolac significantly increased the success rate to 40% (P < .05). Patient's pain during ACP and CLM was significantly lower in the ketorolac group (P < .05). CONCLUSIONS: Ketorolac BI can increase the success rate of anesthesia after IANB and BI with articaine in patients with AIP.

Anesthetic Success of an Inferior Alveolar Nerve Block and Supplemental Articaine Buccal Infiltration for Molars and Premolars in Patients with Symptomatic Irreversible Pulpitis.

INTRODUCTION: The purpose of this retrospective study was to determine the anesthetic success of the inferior alveolar nerve (IAN) block, and supplemental articaine buccal infiltration after a failed IAN block, in first and second molars and premolars in patients presenting with symptomatic irreversible pulpitis. METHODS: As part of 6 studies, 375 emergency patients presenting with symptomatic irreversible pulpitis received 2% lidocaine with 1:100,000 epinephrine via an IAN block. After profound lip numbness, endodontic access and instrumentation were initiated. If the patient felt moderate to severe pain, a supplemental buccal infiltration of a cartridge of 4% articaine with 1:100,000 epinephrine was administered (204 patients), and endodontic treatment continued. Success was defined as the ability to access and instrument the tooth without pain (visual analogue scale rating of 0) or mild pain (visual analogue scale rating less than or equal to 54 mm). RESULTS: IAN block success was 28% for the first molars, 25% for the second molars, and 39% for the premolars. There were no significant differences when comparing molars with premolars. For the supplemental articaine buccal infiltration, success was 42% for the first molars, 48% for the second molars, and 73% for the premolars. There were no significant differences when comparing the molars, but there was a significant difference when comparing the premolars with the molars. CONCLUSIONS: For patients presenting with symptomatic irreversible pulpitis, the success rates for the IAN block and supplemental buccal infiltration of articaine of the molars and premolars would not be high enough to ensure profound pulpal anesthesia.

Infiltration anesthesia for extraction of the mandibular molars.

PURPOSE: Profound anesthesia for mandibular molars by buccal infiltration has been tried in recent years, with promising results. This prospective, randomized, single-blinded, crossover study investigated the clinical anesthetic efficacy obtained with 1:100,000 epinephrine plus 4% articaine (A100) 1.8 versus 3.6 mL as mandibular first molar buccal infiltration during removal of impacted lower third molars. MATERIALS AND METHODS: Thirty adult patients underwent removal of symmetrically positioned impacted lower third molars in 2 separate appointments. The patients randomly received mandibular buccal first molar infiltration of A100 1.8 or 3.6 mL during surgery. For assessment of anesthetic efficacy, any pain during surgery was rated using the visual analog scale. Also, the onset, duration, and total amount of anesthetic used were recorded. RESULTS: Compared with the 1.8-mL volume of A100, the 3.6-mL volume showed a statistically higher success rate (93% vs 56%). CONCLUSIONS: Infiltration in the buccal vestibule opposite the mandibular first molar by A100 3.6 mL may be a good option for extraction of mandibular third molars, with supplemental lingual anesthesia.

Effect of massage on the efficacy of the mental and incisive nerve block.

The purpose of this trial was to assess the effect of soft tissue massage on the efficacy of the mental and incisive nerve block (MINB). Thirty-eight volunteers received MINB of 2.2 mL of 2% lidocaine with 1 : 80,000 epinephrine on 2 occasions. At one visit the soft tissue overlying the injection site was massaged for 60 seconds (active treatment). At the other visit the crowns of the mandibular premolar teeth were massaged (control treatment). Order of treatments was randomized. An electronic pulp tester was used to measure pulpal anesthesia in the ipsilateral mandibular first molar, a premolar, and lateral incisor teeth up to 45 minutes following the injection. The efficacy of pulp anesthesia was determined by 2 methods: (a) by quantifying the number of episodes with no response to maximal electronic pulp stimulation after each treatment, and (b) by quantifying the number of volunteers with no response to maximal pulp stimulation (80 reading) on 2 or more consecutive tests, termed anesthetic success. Data were analyzed by McNemar, Mann-Whitney, and paired-samples t tests. Anesthetic success was 52.6% for active and 42.1% for control treatment for lateral incisors, 89.5 and 86.8% respectively for premolars, and 50.0 and 42.1% respectively for first molars (P = .344, 1.0, and .508 respectively). There were no significant differences in the number of episodes of negative response to maximum pulp tester stimulation between active and control massage. A total of 131 episodes were recorded after both active and control massage in lateral incisors (McNemar test, P = 1.0), 329 (active) versus 316 (control) episodes in the premolars (McNemar test, P = .344), and 119 (active) versus 109 (control) episodes respectively for first molars (McNemar test, P = .444). Speed of anesthetic onset and discomfort did not differ between treatments. We concluded that soft tissue massage after MINB does not influence anesthetic efficacy.

Anaesthetic efficacy of supplemental lingual infiltration of mandibular molars after inferior alveolar nerve block plus buccal infiltration in patients with irreversible pulpitis.

AIM: To investigate the effect of supplemental lingual infiltration (LI) of mandibular molars following an inferior alveolar nerve block (IANB) plus buccal infiltration (BI) in patients with irreversible pulpitis. METHODOLOGY: Eighty adult patients diagnosed with irreversible pulpitis participated in this prospective study. All patients received standard IANB via injection of 4 mL of 2% lidocaine with 1 : 100,000 epinephrine. Ten minutes after the IANB, patients with numbness of the lower lip were randomly divided into two groups. In the BI group, 40 patients received supplemental BI of 0.9 mL of 4% articaine with 1 : 100,000 epinephrine. In the buccal plus lingual infiltration (BLI) group, 40 patients received supplemental BI of 0.9 mL of 4% articaine with 1 : 100,000 epinephrine and, subsequently, LIs with the same anaesthetic solution and dose. Endodontic access cavity preparation began 15 min after the IANB. Pain during treatment was recorded using a Heft-Parker visual analogue scale. Success was defined when pain was 'none' or 'mild' on endodontic access and initial instrumentation. The pain was estimated and statistically analysed by the chi-squared test (α = 0.05). RESULTS: The success rates for the BI and BLI groups were 70% and 62.5%, respectively. No statistical difference was found between the two groups (P = 0.478). CONCLUSIONS: Supplemental LIs are not recommended for administration in mandibular molars with irreversible pulpitis, because they do not improve the anaesthetic success after IANB plus BI.

A prospective, randomized single-blind study of the anesthetic efficacy of frequency-dependent conduction blockade of the inferior alveolar nerve.

INTRODUCTION: The purpose of this prospective, randomized single-blind study was to evaluate the degree of pulpal anesthesia obtained with frequency-dependent conduction blockade of the inferior alveolar nerve (IAN). METHODS: Eighty adult volunteers randomly received two IAN blocks: an IAN block followed by continuous electrical stimulation for 3 minutes of the first molar or lateral incisor for six cycles over a time period of 64 minutes; an IAN block followed by mock electrical stimulation using the same cycles. The IAN blocks were administered at two separate appointments spaced at least 1 week apart in a crossover design. An electric pulp tester was used to test for anesthesia of the first molar and lateral incisor. Anesthesia was considered successful when two consecutive 80 readings were obtained within 15 minutes, and the 80 reading was recorded through the 60th minute. RESULTS: The anesthetic success rate for the stimulated IAN block was 35% and 48% for the lateral incisor and first molar, respectively. For the mock stimulated IAN, success was 18% for the lateral incisor and 62% for the first molar. There was no significant difference between the two IAN block techniques. CONCLUSIONS: We concluded that the stimulation of nerves in the presence of local anesthesia (frequency-dependent nerve block) did not statistically increase the success rate of pulpal anesthesia for an IAN block.

The role of N-methyl-D-aspartate receptor subunits in the rat thalamic mediodorsal nucleus during central sensitization.

We have identified tooth pulp-driven neurons (TPDNs) in the thalamic mediodorsal nucleus (MD) in rats and showed that the TPDNs' responsiveness in the MD is increased by chemical conditioning stimulation of allyl-isothiocyanate (mustard oil) to the molar tooth pulp. The aim of the present study was to address the role of N-methyl-d-aspartate receptors (NMDA receptors) in the sensitized central nervous system following the mustard oil application to the rat tooth pulp. Microinjection of MK-801, a noncompetitive NMDA receptor antagonist, to the thalamic MD nucleus reduced the TPDNs' responsiveness in the thalamic MD nucleus. Gene expression analysis showed that expression levels of NMDA receptor subunits NR2A and NR2D mRNAs in the thalamus were increased by the mustard oil application and that the increases were reduced by MK-801. When naloxone, an opioid receptor antagonist, was given systemically following the MK801 microinjection, the TPDNs' responsiveness was rekindled and expression levels of NR2D and NR2A mRNAs were increased. Moreover, lidocaine pretreatment abolished the mustard oil-induced upregulation of NR2D and NR2A mRNAs. These results suggest that, during central sensitization, interaction of NMDA receptors and endogeneous opioid-related inhibitory mechanisms plays critical role in the alteration of the TPDNs' responsiveness in the thalamic MD nucleus.

Neuron-immune interactions in the sensitized thalamus induced by mustard oil application to rat molar pulp.

We have reported that mustard oil application to the rat dental pulp induces neuronal activation in the thalamus. To address the mechanisms involved in the thalamic changes, we performed neuronal responsiveness recording, immunohistochemistry, and molecular biological analysis. After mustard oil application, neuronal responsiveness was increased in the mediodorsal nucleus. When MK801 (an N-methyl-D-aspartate receptor antagonist) was applied to the mediodorsal nucleus, the enhanced responsiveness was decreased. N-methyl-D-aspartate receptor 2D, glial fibrillary acidic protein, and antigen-presenting cell-related gene mRNAs in the contralateral thalamus were up-regulated at 10 minutes after mustard oil application, but were down-regulated within 10 minutes after the antagonist application. OX6-expressing microglia and glial fibrillary acidic protein-expressing astrocytes did not increase until 60 minutes after mustard oil application. These results suggested that the thalamic neurons play some roles in regulating the glial cell activation in the mediodorsal nucleus via N-methyl-D-aspartate receptor 2D during pulp inflammation-induced central sensitization.

Assessment of the anesthetic effectiveness of anterior and middle superior alveolar injection using a computerized device versus traditional technique in children.

UNLABELLED: The study aims to evaluate the anesthetic effectiveness of the Anterior and Middle Superior Alveolar (AMSA) injection administered through a computer-controlled local anesthetic delivery system (CCLAD), and compare it with the traditional buccal and palatal injections used to anesthetize maxillary primary molars. MATERIALS AND METHODS: The sample included 80 primary maxillary molars, divided into 2 equal groups: Pulpotomy and extraction groups. Each group was divided equally into 4 subgroups: A. First molars anesthetized with the traditional technique, B. first molars anesthetized with the CCLAD, C. second molars anesthetized with the traditional technique, and D. second molars anesthetized with the CCLAD. The evaluation was done single blind using SEM scale. RESULTS: The AMSA injection with the CCLAD was found to be effective in anesthetizing maxillary primary molars in pulpotomy and extraction procedures. There was no significant difference between the two anesthetic techniques except in the step of gingival retraction buccally in, which the traditional injections were more effective than the CCLAD during extractions. No significant difference was found between first and second primary molars in the effectiveness of both techniques. CONCLUSION: The AMSA injection using CCLAD was found to be effective in children.

Articaine for supplemental intraosseous anesthesia in patients with irreversible pulpitis.

The purpose of this study was to determine the anesthetic efficacy and heart rate effect of 4% articaine with 1:100,000 epinephrine for supplemental intraosseous injection in mandibular posterior teeth diagnosed with irreversible pulpitis. Thirty-seven emergency patients, diagnosed with irreversible pulpitis of a mandibular posterior tooth, received an inferior alveolar nerve block and had moderate-to-severe pain upon endodontic access. The Stabident system was used to administer 1.8 ml of 4% articaine with 1:100,000 epinephrine. Success of the intraosseous injection was defined as none or mild pain upon endodontic access or initial instrumentation. The results demonstrated that anesthetic success was obtained in 86% (32 of 37) of the patients. Maximum mean heart rate was increased 32 beats/minute during the intraosseous injection. We can conclude that when the inferior alveolar nerve block fails to provide profound pulpal anesthesia, the intraosseous injection of 4% articaine with 1:100,000 epinephrine would be successful 86% of the time in achieving pulpal anesthesia in mandibular posterior teeth of patients presenting with irreversible pulpitis.

Proportion of unmyelinated axons in rat molar and incisor tooth pulps following neonatal capsaicin treatment and/or sympathectomy.

The occurrence of unmyelinated axons was examined ultrastructurally in rat molar and incisor root pulps of normal rats, of neonatally capsaicin-treated rats, of rats subjected to neonatal capsaicin treatment followed by resection of the superior cervical ganglion and of sympathectomized but otherwise normal rats. Following capsaicin treatment the occurrence of unmyelinated pulpal axons was slightly subnormal. Sympathectomy was largely without effect on the population of unmyelinated axons in tooth pulps of capsaicin-treated rats. In normal rats the proportion of unmyelinated axons in molar pulps was not altered by sympathectomy but it caused a slight decrease in the number of unmyelinated incisor pulpal axons. These findings support the view that most of the unmyelinated axons in rat molar and incisor pulps are sensory, that the parent neurons of these axons differ from nociceptive neurons at other sites by being largely resistant to neonatal capsaicin treatment and that very few unmyelinated tooth pulp axons represent postganglionic efferents.