John Nusstein

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.

SEM Observations of Nickel-Titanium Rotary Endodontic Instruments that Fractured During Clinical Use

Numerous discarded ProFile GT, ProFile, and ProTaper nickel-titanium rotary instruments obtained from two graduate endodontic clinics were examined by scanning electron microscopy. These instruments had an unknown history of clinical use and had fractured or experienced considerable permanent torsional deformation without complete separation. The failure processes generally exhibited substantial ductile character, evidenced by a dimpled rupture fracture surface. Crack propagation at grain boundaries and cleavage surfaces indicative of transgranular fracture were observed for some specimens. It appeared that oxide particles from the manufacturing process served as nucleating sites for the microvoids, leading to dimpled rupture. A previously unreported fracture mode also was observed, in which crack propagation, approximately parallel to the local flute orientation, connected pitted regions on the surface. Combining present and previous scanning electron microscopy observations of clinically failed instruments, suggestions are offered for improving their fracture resistance.

Articaine for Supplemental Buccal Mandibular Infiltration Anesthesia in Patients with Irreversible Pulpitis When the Inferior Alveolar Nerve Block Fails

The purpose of this prospective study was to determine the anesthetic efficacy of the supplemental buccal infiltration injection of a cartridge of 4% articaine with 1:100,000 epinephrine in mandibular posterior teeth diagnosed with irreversible pulpitis when the conventional inferior alveolar nerve (IAN) block failed. Fifty-five emergency patients, diagnosed with irreversible pulpitis of a mandibular posterior tooth, received an IAN block and had moderate to severe pain on endodontic access. An infiltration of a cartridge of 4% articaine with 1:100,000 epinephrine was administered buccal to the tooth requiring endodontic treatment. Success of the infiltration injection was defined as no pain or mild pain on endodontic access or instrumentation. The results showed that anesthetic success was obtained in 58% of the mandibular posterior teeth. We can conclude that when the IAN block fails to provide profound pulpal anesthesia, the supplemental buccal infiltration injection of a cartridge of 4% articaine with 1:100,000 epinephrine would be successful 58% of the time for mandibular posterior teeth in patients presenting with irreversible pulpitis. Unfortunately, the modest success rate would not provide predictable pulpal anesthesia for all patients requiring profound anesthesia.

A Prospective, Randomized, Double-blind Comparison of Articaine and Lidocaine for Maxillary Infiltrations

The purpose of this prospective, randomized, double-blind crossover study was to evaluate the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine and 2% lidocaine with 1:100,000 epinephrine in maxillary lateral incisors and first molars. Eighty subjects randomly received, in a double-blind manner, maxillary lateral incisor and first molar infiltrations of one cartridge of 4% articaine with 1:100,000 epinephrine or 2% lidocaine with 1:100,000 epinephrine at two separate appointments spaced at least 1 week apart. In maxillary lateral incisors, articaine exhibited a significantly higher anesthetic success rate of 88% when compared with a 62% success rate with lidocaine. In maxillary first molars, articaine had a similar success rate to lidocaine (78% vs 73%), and there was no significant difference between the two solutions. In conclusion, a maxillary infiltration of 4% articaine with 1:100,000 epinephrine statistically improved anesthetic success when compared with 2% lidocaine with 1:100,000 epinephrine in the lateral incisor but not in the first molar.

Comparison of the Anesthetic Efficacy of the Conventional Inferior Alveolar, Gow-Gates, and Vazirani-Akinosi Techniques

The purpose of this prospective, randomized study was to compare the degree of pulpal anesthesia obtained with the conventional inferior alveolar, the Gow-Gates, and the Vazirani-Akinosi techniques in vital, asymptomatic teeth. With a crossover design, 40 subjects received all 3 techniques in a random manner by using 3.6 mL of 2% lidocaine with 1:100,000 epinephrine at 3 separate appointments. An electric pulp tester was used to test for anesthesia in 3-minute cycles for 60 minutes of the first molars, first premolars, and lateral incisors. Anesthesia was considered successful when 2 consecutive 80 readings were obtained within 15 minutes, and the 80 reading was continuously sustained through the 60th minute. The ranges of successful anesthesia were as follows: inferior alveolar technique, 25%-62%; Gow-Gates technique, 16%-44%; and for the Vazirani-Akinosi technique, 13%-50%. There was no significant difference (P > .05) in success among the 3 techniques. However, the Gow-Gates and Vazirani-Akinosi techniques resulted in a statistically slower onset of pulpal anesthesia than the inferior alveolar nerve block. We concluded that in vital, asymptomatic teeth and for the subjects who achieved lip numbness, the conventional inferior alveolar nerve block is similar to the Gow-Gates and Vazirani-Akinosi techniques regarding anesthetic success but has a faster onset of pulpal anesthesia.

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.

Effect of Preoperative Ibuprofen on the Success of the Inferior Alveolar Nerve Block in Patients with Irreversible Pulpitis

INTRODUCTION The purpose of this prospective, randomized, double-blind, placebo-controlled study was to determine the effect of the administration of preoperative ibuprofen on the success of the inferior alveolar nerve block (IAN) in patients with irreversible pulpitis. METHODS One hundred endodontic emergency patients diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a double-blind manner, identical capsules of either 800 mg ibuprofen or placebo 45 minutes before the administration of a conventional IAN block. Access was begun 15 minutes after completion of the IAN block, and all patients had profound lip numbness. Success was defined as no or mild pain (visual analogue scale recordings) on access or initial instrumentation. RESULTS AND CONCLUSIONS The success rate for the IAN block was 41% with ibuprofen and 35% with placebo, with no significant difference (P=.57) between the 2 groups. For mandibular posterior teeth, a dose of 800 mg of ibuprofen given 45 minutes before the administration of the IAN block did not result in a statistically significant increase in anesthetic success in patients with irreversible pulpitis.

Effect of combination of preoperative ibuprofen/acetaminophen on the success of the inferior alveolar nerve block in patients with symptomatic irreversible pulpitis.

INTRODUCTION The purpose of this prospective, randomized, double-blind, placebo-controlled study was to determine the effect of the administration of the combination of preoperative ibuprofen/acetaminophen on the success of the inferior alveolar nerve (IAN) block in patients with symptomatic irreversible pulpitis. METHODS One hundred endodontic emergency patients in moderate to severe pain diagnosed with irreversible pulpitis of a mandibular posterior tooth randomly received, in a double-blind manner, identical capsules of either a combination of 800 mg ibuprofen and 1000 mg acetaminophen or placebo 45 minutes before the administration of a conventional IAN block. Access was begun 15 minutes after completion of the IAN block, and all patients had profound lip numbness. Success was defined as no or mild pain (visual analog scale recordings) on access or initial instrumentation. RESULTS AND CONCLUSIONS The success rate for the IAN block was 32% for the combination ibuprofen/acetaminophen group and 24% for the placebo, with no significant difference (P = .37) between the 2 groups. For mandibular posterior teeth, a combination dose of 800 mg ibuprofen and 1000 mg acetaminophen given 45 minutes before administration of the IAN block did not result in a statistically significant increase in anesthetic success in patients with symptomatic irreversible pulpitis.

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.