with epinephrine 1:200,000 Septocaine with epinephrine 1:200,000 Articadent with epinephrine 1:200,000 Orabloc (articaine hydrochloride 4% and epinephrine 1:200,000) An epinephrine-free (adrenaline-free) version is available in Europe under the brand name Ultracain D. However, version with epinephrine (adrenaline) is available in Europe under the brand name Supracain 4% with epinephrine concentration of 1:200,000. Structure and metabolism The amide structure of articaine is similar to that of other local anesthetics, but its molecular structure differs through the presence of a thiophene ring instead of a benzene ring. Articaine is exceptional because it contains an additional ester group that is metabolized by esterases in blood and tissue. The elimination of articaine is exponential with a half-life of 20 minutes. Since articaine is hydrolized very quickly in the blood, the risk of systemic intoxication seems to be lower than with other anesthetics, especially if repeated injection is performed. Clinical use Articaine is used for pain control. Like other local anesthetic drugs, articaine causes a transient and completely reversible state of anesthesia (loss of sensation) during (dental) procedures. In dentistry, articaine is used mainly for infiltration injections. Articaine, while not proven, has been associated with higher risk of nerve damage when used as a block technique. However, articaine is able to penetrate dense cortical bone — as found in the lower jaw (mandible) — more than most other local anaesthetics. In people with hypokalemic sensory overstimulation, lidocaine is not very effective, but articaine works well. Studies comparing lidocaine and articaine found that articaine is more effective than lidocaine in anaesthetising the posterior first molar region. Articaine has been found to be 3.81 times more likely than lidocaine to produce successful anaesthesia when used for infiltration injections. However, there is no evidence to support the use of articaine over lidocaine for inferior alveolar nerve blocks. Furthermore, articaine has been demonstrated to be superior to lidocaine for use of supplementary infiltration following persistent pain despite a successful inferior dental nerve block with lidocaine. Contraindications Allergy to amide-type anesthetics Allergy to metabisulfites Idiopathic or congenital methemoglobinemia (not a concern in dental practice due to the small volumes of articaine used) Hemoglobinopathy, such as sickle cell disease Articaine is not contraindicated in patients with sulfa allergies, as there is no cross-allergenicity between articaine's sulphur-bearing thiophene ring and sulfonamides. Methylparaben is no longer present in any dental local anesthetic formula available in North America. Paresthesia controversy Paresthesia, a short-to-long-term numbness