Conditions: Pain
Keywords: mepivacaine lidocaine inferior alveolar nerve block pulpal anesthesia mepivacaine/lidocaine lidocaine/lidocaine
Allocation: RANDOMIZED | Intervention model: CROSSOVER
Enrollment: 100
Healthy volunteers: yes

Brief summary:
The inferior alveolar nerve block (shot) is the most frequently used injection technique for achieving local anesthesia (numbness) for the teeth in the lower jaw. However, this injection does not always result in successful pulpal (tooth) anesthesia (patient felt pain). No study has combined mepivacaine and lidocaine anesthetics (numbing solutions) for this type of injection (shot). The investigators propose to compare an injection of mepivacaine followed by lidocaine to an injection of lidocaine followed by lidocaine to determine if there is a difference in effectiveness.

Detailed description:
One hundred adult male and female subjects will randomly receive two sets of inferior alveolar block injections (shots) consisting of; 1.) an injection of 1.8 mL of 3% mepivacaine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine, and 2.) an injection of 1.8 mL of 2% lidocaine with 1:100,000 epinephrine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine, at two separate appointments spaced at least two weeks apart, in a crossover design. Whether the subject receives the mepivacaine or the lidocaine for the first injection will be determined randomly. The doctor will not know whether the subject receives mepivacaine or lidocaine for the first injection. The subject will not know which anesthetics he/she receives. A pulp tester will be used to test the lower jaw teeth (molars, premolars, and incisors) for anesthesia (numbness) in 4-minute time cycles for 60 minutes. The data will be statistically analyzed.

Arms:
arm 1: A repeated measures design utilizing a single group of subjects was employed with each subject serving as his/her own control. Each subject received two interventions: 1.) 1.8 cc 3% mepivacaine and 1.8 cc 2% lidocaine with 1:100,000 epinephrine (3% mepivacaine/2% lidocaine with epinephrine - combination 1) and 2.) 1.8 cc 2% lidocaine with 1:100,000 epinephrine followed by 1.8 cc 2% liocaine with 1:100,000 epinephrine at two seperate appointments spaced 2 weeks apart. arm 2: A repeated measures design utilizing a single group of subjects was employed with each subject serving as his/her own control. Each subject received two interventions: 1.) 1.8 cc 2% lidocaine with 1:100,000 epinephrine and 1.8 cc 2% lidocaine with 1:100,000 epinephrine and 2.) 1.8 cc 3% mepivacaine and 1.8 cc 2% lidocaine with 1:100,000 epinephrine followed by 1.8 cc 2% liocaine with 1:100,000 epinephrine at two separate appointments spaced two weeks apart.

Interventions: intervention 1: mepivacaine + lidocaine followed by lidocaine +lidocaine intervention 2: lidocaine + lidocaine followed by mepivacaine + lidocaine
Intervention descriptions: intervention 1: 1.8 mL of 3% mepivacaine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine intervention 2: 1.8 mL of 2% lidocaine with 1:100,000 epinephrine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine followed by 1.8 mL of 3% mepivacaine followed by 1.8 mL of 2% lidocaine with 1:100,000 epinephrine

Protocol document: