Joel M. Weaver

Anesthetic efficacy of articaine for inferior alveolar nerve blocks in patients with irreversible pulpitis.

The purpose of this prospective, randomized, double-blind study was to compare the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine to 2% lidocaine with 1:100,000 epinephrine for inferior alveolar nerve blocks in patients experiencing irreversible pulpitis in mandibular posterior teeth. Seventy-two emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a double-blind manner, 2.2 ml of 4% articaine with 1:100,000 epinephrine or 2.2 ml of 2% lidocaine with 1:100,000 epinephrine using a conventional inferior alveolar nerve block. Endodontic access was begun 15 min after solution deposition, and all patients were required to have profound lip numbness. Success was defined as none or mild pain (Visual Analogue Scale recordings) on endodontic access or initial instrumentation. The success rate for the inferior alveolar nerve block using articaine was 24% and for the lidocaine solution success was 23%. There was no significant difference (p = 0.89) between the articaine and lidocaine solutions. Neither solution resulted in an acceptable rate of anesthetic success in patients with irreversible pulpitis.

An evaluation of an electric pulp tester as a measure of analgesia in human vital teeth

The purpose of this study was to evaluate, with theAnalytic Technology electric pulp tester, clinical analgesia in normal, asymptomatic, and symptomatic human vital teeth. Group A consisted of 34 teeth that were classified as normal. Group B consisted of 33 asymptomatic teeth that had restorations, caries, or crown fracture. Group C consisted of 30 teeth with the clinical diagnosis of irreversible pulpitis. Two cartridges (3.6 ml) of 2% lidocaine with 1:100,000 epinephrine were administered by block and/or infiltration. The teeth were tested at various time intervals to determine if they responded to the maximum output (80/80) from the electric pulp tester. If the teeth responded, periodontal ligament injections were given until no response was recorded with the pulp tester. Clinical analgesia was then tested by performing endodontic procedures. The normal and asymptomatic groups had analgesia 100% of the time. In the teeth with irreversible pulpitis, 73% had clinical analgesia.

An evaluation of volumes and concentrations of lidocaine in human inferior alveolar nerve block

The purpose of this study was to evaluate, with the electric pulp tester, the anesthetic efficacy of 1.8 ml of 2% lidocaine with 1:100,000 epinephrine, 3.6 ml of 2% lidocaine with 1:200,000 epinephrine, and 1.8 ml of 4% lidocaine with 1:100,000 epinephrine in human inferior alveolar nerve block. Thirty subjects randomly received each of the solutions at three successive appointments. The first molar, canine, lateral incisor, and contralateral canine were tested with the pulp tester at various time intervals up to 55 min. Complete anesthesia was defined as an 80/80 reading with the pulp tester. No significant differences in anesthetic success or failure were found among the three solutions. Potential anesthetic problems (failure, noncontinuous anesthesia, slow onset, and short duration) occurred in 43 to 57% of the molars, in 43 to 60% of the canines, and in 57 to 80% of the lateral incisors. Complete anesthesia in the mandible is a meaningful clinical problem.

Anesthetic efficacy of the supplemental intraosseous injection of 3% mepivacaine in irreversible pulpitis

OBJECTIVE To determine the efficacy of a supplemental intraosseous injection of 3% mepivacaine in mandibular posterior teeth with irreversible pulpitis. Intraosseous injection pain, subjective heart rate increase, and pain ratings during endodontic treatment were also assessed. STUDY DESIGN Forty-eight patients with irreversible pulpitis received conventional inferior alveolar nerve blocks. Electric pulp testing was used to determine pulpal anesthesia. Patients who were positive to the pulp testing, or negative to pulp testing but felt pain during endodontic treatment, received an intraosseous injection of 1.8 ml of 3% mepivacaine. A second intraosseous injection of 3% mepivacaine (1.8 ml) was given if the first injection was unsuccessful. RESULTS Seventy-five percent of patients required an initial intraosseous injection because of failure to gain pulpal anesthesia. The inferior alveolar block was 25% successful; the first intraosseous injection increased success to 80%. A second intraosseous injection further increased success to 98%. These differences were significant (p < 0.05). Eight percent (4/48) of the initial intraosseous injections resulted in solution being expressed into the oral cavity: these were considered technique failures. CONCLUSIONS For mandibular posterior teeth with irreversible pulpitis, a supplemental intraosseous injection of 3% mepivacaine increased anesthetic success. A second intraosseous injection, when necessary, further improved success.

Anesthetic Efficacy of the Supplemental X-tip Intraosseous Injection in Patients with Irreversible Pulpitis

The purpose of this study was to determine the anesthetic efficacy of the supplemental intraosseous injection, using the X-tip system in an apical location, in mandibular posterior teeth diagnosed with irreversible pulpitis when the conventional inferior alveolar nerve block failed. Thirty-three emergency patients, diagnosed with irreversible pulpitis of a mandibular posterior tooth, received an inferior alveolar nerve block and had moderate-to-severe pain on endodontic access. The X-tip system was used to administer 1.8 ml of 2% lidocaine with 1:100,000 epinephrine. The X-tip injection site was 3- to 7-mm apical to the mucogingival junction of the affected tooth. Success of the X-tip intraosseous injection was defined as none or mild pain on endodontic access or initial instrumentation. The results of this study demonstrated that 6 of 33 (18%) X-tip injections resulted in backflow of anesthetic solution into the oral cavity; none were successful in obtaining anesthesia. Twenty-seven of the remaining 33 X-tip injections (82%) were successful. We conclude that when the inferior alveolar nerve block fails to provide profound pulpal anesthesia, the X-tip system, when used in an apical location and when there was no backflow of the anesthetic solution into the oral cavity, was successful in achieving pulpal anesthesia in mandibular posterior teeth of patients presenting with irreversible pulpitis.

The significance of needle deflection in success of the inferior alveolar nerve block in patients with irreversible pulpitis.

The purpose of this prospective, randomized, blinded study was to compare the anesthetic efficacy of the conventional inferior alveolar nerve block, administered with the needle bevel oriented away from the mandibular ramus, to the bidirectional-needle-rotation technique, administered using the computer-assisted Wand II anesthesia system, in patients diagnosed with irreversible pulpitis. Sixty-four emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a blinded manner, 2.8 ml of 2% lidocaine with 1:100,000 epinephrine using either a conventional inferior alveolar nerve block or a bidirectional-needle-rotational technique using the Wand II injection system. The conventional inferior alveolar nerve block was administered with the needle bevel oriented away from the mandibular ramus so the needle would deflect inward toward the mandibular foramen. The bidirectional-needle-rotation technique was administered by rotating the Wand handpiece assembly in a clockwise-counterclockwise movement (like an endodontic hand file) to minimize needle deflection. Endodontic access was begun 17 min after solution deposition, and all patients were required to have profound lip numbness. Success was defined as none or mild pain (VAS recordings) on endodontic access or initial instrumentation. The results of this study showed no significant differences (p > 0.05) between the success rates of the two techniques. The conventional inferior alveolar nerve block, with the needle bevel oriented away from the mandibular ramus, had a 50% success rate. The bidirectional-needle-rotation technique with the Wand II had a 56% success rate. Neither technique resulted in an acceptable rate of anesthetic success in patients with irreversible pulpitis.

Anesthetic efficacy of the intraosseous injection of 2% lidocaine (1:100,000 epinephrine) and 3% mepivacaine in mandibular first molars

OBJECTIVES This study compared the anesthetic efficacy of a primary intraosseous injection of 2% lidocaine with 1:100,000 epinephrine and 3% mepivacaine in human mandibular first molars. Injection pain and healing postoperatively were also assessed for the intraosseous injection. STUDY DESIGN With the use of a repeated-measures design, 42 subjects randomly received intraosseous injections of 1.8 ml of 2% lidocaine with 1:100,000 epinephrine or 1.8 ml of 3% mepivacaine in a double-blind manner at two successive appointments. The first molar and adjacent teeth were blindly tested with an electric pulp tester at 2-minute cycles for 60 minutes. Anesthetic success was defined as no subject response to the maximum output of the pulp tester (80 reading) for two consecutive readings. RESULTS Anesthetic success occurred in 74% of the first molars with 2% lidocaine with 1:100,000 epinephrine and in 45% with 3% mepivacaine. The difference was statistically significant (p < 0.05). Overall, onset was rapid for the intraosseous injections, the duration of pulpal anesthesia steadily declined over the 60 minutes, the majority of the subjects had no pain or mild pain with perforation and solution deposition, and 5% of the subjects had delayed healing at the perforation sites. CONCLUSIONS The results of this study indicate that the primary intraosseous injection of 2% lidocaine with 1:100,000 epinephrine is more successful and results in a longer duration of pulpal anesthesia as compared with 3% mepivacaine in noninflamed mandibular first molars. Most subjects reported no or mild pain during perforation and injection.

Comparison of the efficacy of esmolol and alfentanil to attenuate the hemodynamic responses to emergence and extubation

STUDY OBJECTIVE To define the ability of esmolol and alfentanil to control the hemodynamic changes associated with extubation and emergence. DESIGN Randomized, double-blind, placebo-controlled study. SETTING General surgery operating rooms at a university hospital. PATIENTS Forty-two ASA physical status I and II patients without history of cardiac or pulmonary disease undergoing surgery not involving the cranium or thorax. INTERVENTIONS Patients were given either a bolus dose of normal saline followed by an infusion of normal saline, a bolus dose of alfentanil 5 micrograms/kg followed by an infusion of normal saline, or a bolus dose of esmolol 500 micrograms/kg followed by an infusion of esmolol 300 micrograms/kg/min. MEASUREMENTS AND MAIN RESULTS Emergency and extubation resulted in significant increases in heart rate (HR) and blood pressure (BP) in the placebo group. Alfentanil controlled the responses to emergence but prolonged the time to extubation (p < 0.05). Esmolol significantly controlled the responses to emergence and extubation (p < 0.05). CONCLUSIONS Emergence and extubation after inhalation general anesthesia result in significant increases in BP and HR in healthy patients. An esmolol bolus dose and subsequent infusion significantly attenuated these responses. A small bolus dose of alfentanil minimized the responses to emergence but prolonged the time to extubation and was no longer protective at that point.

Anesthetic efficacy and heart rate effects of the supplemental intraosseous injection of 2% mepivacaine with 1:20,000 levonordefrin

OBJECTIVE The purpose of this study was to determine the anesthetic efficacy and heart rate effects of a supplemental intraosseous injection of 2% mepivacaine with 1:20,000 levonordefrin. STUDY DESIGN Through use of a repeated-measures design, 40 subjects randomly received 3 combinations of injections at 3 separate appointments. The combinations were as follows: inferior alveolar nerve (IAN) block (with 3% mepivacaine) + intraosseous injection of 1.8 mL of 2% mepivacaine with 1:20,000 levonordefrin; IAN block + intraosseous injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine (positive control); IAN block + mock intraosseous injection (negative control). Each first molar, second molar, and second premolar was blindly tested with a pulp tester at 2-minute cycles for 60 minutes after injection. Anesthesia was considered successful when 2 consecutive readings of 80 were obtained. Heart rate (pulse rate) was measured with a pulse oximeter. RESULTS One hundred percent of the subjects had lip numbness with the IAN block + intraosseous mock technique and IAN block + intraosseous techniques. The anesthetic success rates for IAN block + mock intraosseous injection, IAN block + intraosseous lidocaine, and IAN block + intraosseous mepivacaine, respectively, were as follows: 80%, 100%, and 100% for the first molar; 90%, 100%, and 100% for the second molar; 77%, 97%, and 97% for the second premolar. For the first molar and second premolar, the differences were significant (P< .05) when the intraosseous mepivacaine and lidocaine techniques were compared with the IAN block + mock intraosseous injection. There were no significant differences between the intraosseous mepivacaine and lidocaine techniques. Eighty percent of the subjects had a mean increase in heart rate of 23-24 beats per minute with the intraosseous injection of the mepivacaine and lidocaine solutions; there were no significant differences between results with the 2 solutions. CONCLUSIONS We concluded that intraosseous injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine or 2% mepivacaine with 1:20,000 levonordefrin, used to supplement an IAN block, significantly increased anesthetic success in first molars and second premolars. The 2 solutions were equivalent with regard to intraosseous anesthetic success rate, failure rate, and heart rate increase after IAN block.

Anesthetic Effectiveness of the Supplemental Intraligamentary Injection, Administered with a Computer-Controlled Local Anesthetic Delivery System, in Patients with Irreversible Pulpitis

The purpose of this study was to determine the anesthetic effectiveness of the supplemental intraligamentary injection, administered with a computer-controlled local anesthetic delivery system, in mandibular posterior teeth diagnosed with irreversible pulpitis when the conventional inferior alveolar nerve block failed. Fifty-four 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. A computer-controlled local anesthetic delivery system was then used to administer intraligamentary injections of 1.4 ml of 2% lidocaine with 1:100,000 epinephrine. Success of the intraligamentary injection was defined as none or mild pain upon endodontic access or initial instrumentation. The results demonstrated that anesthetic success was obtained in 56% (30 of 54) of the patients. We concluded that when the inferior alveolar nerve block failed to provide profound pulpal anesthesia in mandibular posterior teeth of patients presenting with irreversible pulpitis, the intraligamentary injection administered with a computer-controlled local anesthetic delivery system was successful approximately 56% of the time.