In a recent article for the American Association of Endodontists entitled “Successful Local Anesthesia: What Endodontists Need to Know,” Dr. Al W. Reader, professor emeritus and program director of advanced endodontics at Ohio State University and former director of the American Board of Endodontics, discusses local anesthesia techniques for endodontists that can improve patient outcomes.

According to Reader, there is no “magical solution” for anesthetizing patients who are in pain and suffering from pulpitis. In other words, there isn’t a “technique for nerve block” that offers “predictive pulpal anesthesia” in patients. Instead, in most patients, supplemental techniques tend to be more predictably effective. Reader cites a text written by himself in collaboration with J. Nusstein and M. Drum, “Successful Local Anesthesia for Restorative Dentistry and Endodontics,” concluding that inferior alveolar nerve block (IANB) is successful less than half of the time in completely (or nearly completely) eliminating discomfort for patients during a procedure: 28 percent of the time for first molars, 25 percent for second molars and 39 percent for the premolars. Reader sums it up thusly: IANB won’t completely eliminate pain in all patients. But, it’s important to remember that this is not the fault of the endodontist.

Local Anesthesia Options for Endodontics

Fortunately, there are a number of options available to endodontists that will improve their ability to effectively anesthetize a patient prior to a procedure. Before examining local anesthesia techniques for endodontists that increase the success rate for eliminating patient discomfort, Reader first looks at techniques that either don’t work in and of themselves, or fail to augment the existing success rates associated with IANB.

Reader claims that conscious sedation is ineffective for pain reduction by its very nature, as patients will still be able to detect pain. Meanwhile, he cites a study conducted by himself in collaboration V. Click, M. Drum, J. Nusstein, and M. Beck which concludes that the Gow-Gates technique produces similar results to IANB: a success rate of 35 percent. Similarly, Reader mentions another study which determined that buffered lidocaine application fails to increase the rate of success, along with one that points to the ineffectiveness of supplemental buccal infiltration of articaine. Finally, Reader asserts that preemptive administration of medications such as ibuprofen, acetaminophen, hydrocodone and others have produced mixed results in terms of improving IANB success rates.

Local Anesthesia Techniques

Having eliminated these possibilities, Reader moves on to examine techniques that have proved successful in increasing a patient’s likelihood to experience little to no discomfort during a procedure.

According to Reader, the administration of a supplemental intraosseous injection has a success rate of 90 percent, with “immediate” onset and a “very good” duration. Similarly, a supplemental intraligamentary injection increases success rates significantly, but with a “fairly short” anesthetic duration. Nitrous oxide proves useful in patients who fail to respond to intraosseous or intraligamentary injections. Intrapulpal anesthesia can be used in patients who fail to experience pulpal anesthesia. Further, Reader cites a study which claims that buffered lidocaine fails to decrease the pain associated with incision and drainage procedures.

Additional Local Anesthesia Options

In closing, Reader examines a handful of new anesthetic formulations. Kovanaze, a combination of tetracaine topical anesthetic and oxymetazoline formulated as a nasal spray, has recently been approved for use in dental procedures. While Reader believes further research is necessary, it could present a viable option for patients who are particularly averse to needles. Exparel, or liposomal bupivacaine, applied as an infiltration failed to adequately control pain in patients; however, Reader suggests that it might work if applied as a nerve block. First, though, the FDA would need to approve it for said use. While Reader’s analysis makes it clear that local anesthesia techniques for endodontists is far from foolproof, significant strides have been made to increase the likelihood of effective pain management during a procedure. Reader speculates that the future will bring further such improvements.

Nima Dayani, D.D.S., M.S. –