Buffered Versus Non-Buffered Lidocaine With Epinephrine for Mandibular Nerve Block: Clinical Outcomes

Outcomes for peak blood levels were assessed for buffered 2% lidocaine with 1:100,000 epinephrine compared with non-buffered 2% lidocaine with 1:100,000 epinephrine. In this institutional review board-approved prospective, randomized, double-blinded, crossover trial, the clinical impact of buffered 2% lidocaine with 1:100,000 epinephrine (Anutra Medical, Research Triangle Park, Cary, NC) was compared with the non-buffered drug. Venous blood samples for lidocaine were obtained 30 minutes after a mandibular nerve block with 80 mg of the buffered or unbuffered drug. Two weeks later, the same subjects were tested with the alternate drug combinations. Subjects also reported on pain on injection with a 10-point Likert-type scale and time to lower lip numbness. The explanatory variable was the drug formulation. Outcome variables were subjects' peak blood lidocaine levels, subjective responses to pain on injection, and time to lower lip numbness. Serum lidocaine levels were analyzed with liquid chromatography-mass spectrometry. Statistical analyses were performed using Proc TTEST (SAS 9.3; SAS Institute, Cary, NC), with the crossover option for a 2-period crossover design, to analyze the normally distributed outcome for pain. For non-normally distributed outcomes of blood lidocaine levels and time to lower lip numbness, an assessment of treatment difference was performed using Wilcoxon rank-sum tests with Proc NPAR1WAY (SAS 9.3). Statistical significance was set at a P value less than .05 for all outcomes. Forty-eight percent of subjects were women, half were Caucasian, 22% were African American, and 13% were Asian. Median age was 21 years (interquartile range [IQR], 20-22 yr), and median body weight was 147 lb (IQR, 130-170 lb). Median blood levels (44 blood samples) at 30 minutes were 1.19 μg/L per kilogram of body weight. Mean blood level differences of lidocaine for each patient were significantly lower after nerve block with the buffered drug compared with the non-buffered agent (P < .01). Mean score for pain on injection for nerve block (n = 46 scores) was 3.3 (standard deviation, 0.9). Seventy-eight percent of subjects reported lower or the same pain scores with the buffered drug; 61% of subjects reported a shorter time to lower lip numbness with the buffered drug. Buffering 2% lidocaine with epinephrine can produce clinical outcomes favorable for subjects and clinicians without clinically detrimental peak blood lidocaine levels

Buffered 1% Lidocaine With Epinephrine Can Be as Effective as Nonbuffered 2% Lidocaine With Epinephrine for Maxillary Field Block

Buffering local anesthetics with epinephrine (Epi) offers clinicians options not often considered. This study assessed outcomes for pulpal anesthesia, pain on injection, and time to midface numbness for buffered 1% lidocaine with 1:100,000 Epi versus nonbuffered 2% lidocaine with 1:100,000 Epi. In this trial with a randomized, crossover design, buffered 1% lidocaine was compared with nonbuffered 2% lidocaine. Subjects were adult volunteers who served as their own controls. The predictor variables were alternate drug formulations. The outcome variables were subjects' responses to cold and electric pulp testing (EPT) stimulation of the maxillary first molar and canine, pain levels during the injection, and time to midface numbness. After maxillary field blocks with 40 mg of buffered lidocaine or 80 mg of nonbuffered lidocaine, subjects reported pain on injection and responses of the maxillary first molar and canine after cold and EPT stimulation. Teeth were tested before field block and at 30-minute intervals until a positive response was detected. Two weeks later, subjects were tested with the alternate drug combinations. For all outcome variables, assessment of treatment difference, calculated as 1% buffered minus 2% nonbuffered, was performed with the Wilcoxon rank sum test with significance at P < .05. More of the 24 subjects were women and Caucasian. The median age was 23.5 years (interquartile range, 21, 25 years), and the median body weight was 155 lb (interquartile range, 128.5, 176.5 lb). Pain levels during the injection were significantly lower for 1% buffered lidocaine, with P = .04. Times to response after injection were not significantly different between the 2 drug formulations for the cold test on a molar, with P = .08, or the cold test on a canine, with P = .22. However, times to response were significantly longer for nonbuffered drugs for EPT on the molar and canine, both with P = .01. Buffering 1% lidocaine with 1:100,000 Epi reduces the pain on injection with a maxillary field block and results in similar lengths of pulpal anesthesia tested with a cold stimulus as compared with nonbuffered 2% lidocaine with 1:100,000 Epi

Management of Pain & Anxiety in the dental office

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Management of Pain and Anxiety in the Dental Office

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Initial Injection Pressure for Dental Local Anesthesia: Effects on Pain and Anxiety

This study quantitatively assessed injection pressure, pain, and anxiety at the start of injection of a local anesthetic into the oral mucosa, and confirmed the relationship between injection pressure and pain, as well as between injection pressure and anxiety. Twenty-eight healthy men were selected as subjects and a 0.5-inch (12 mm) 30-gauge disposable needle attached to a computer-controlled local anesthetic delivery system (the Wand) was used. A 0.5 mL volume of local anesthetic solution was injected submucosally at a speed of either 30 or 160 s/mL. Three seconds after the start of local anesthetic injection, injection pressure was measured and pain and anxiety were assessed. Injection pressure was measured continuously in real time by using an invasive sphygmomanometer and analytical software, and pain was assessed on the Visual Analogue Scale and anxiety on the Faces Anxiety Scale. A significant correlation was evident between injection pressure and pain (rs = .579, P = .00124) and between intensity of injection pressure and state anxiety (rs = .479, P = .00979). It is therefore recommended that local anesthetic be injected under low pressure (less than 306 mm Hg) to minimize pain and anxiety among dental patients