I recently received an e-mail from a Dentist in Canada after he read the post I did on October 20, 2011 entitled “Inferior Alveolar Nerve Block”. What prompted the original post was a wave of missing this block in my office. I went back and did some research on how the block works, how often it is effective (or not), and shared some technique tips for increasing how often it works the first time. I will say that incorporating the things from the post made a huge difference for me, and I have not had a “spell” of missed blocks since, just the usual one here and there that doesn’t work.
When I first read Andrew’s E-mail I have to confess in my head I said “Actually I haven’t noticed this.” Of course one of the things that I know about learning is that once I learn something it seems to show up all the time and I wonder how often in the past I simply didn’t see the signs before. Andrew’s e-mail worked the same way. I started observing the tension in the muscles, the feel of the needle penetration, and sure enough it seemed to correlate to the times I had to go in and block a second time. With a week or two of observational data, I decided to try it out, and the results have me committed to continuing the technique. I have used a similar process for years prior to taking a Centric Relation bite record, so it shouldn’t surprise me that it is successful. I ask my patients to uncross their ankles, take three deep breaths through their diaphragm and relax their shoulders. Here is the original e-mail:
Any dentist who has administered a mandibular block will note that there are times when the needle will “float” to its’ mark, and other times when it requires effort, even force, to insert. The latter scenario often results in discomfort and a lower rate of success in achieving profound anesthesia. The difference is all about the state of the buccinator muscle as it spans ahead of the ascending ramus and attaches to the pterygomandibular ligament. If the buccinator is relaxed, the needle floats, allowing the clinician to proceed effortlessly, and to feel the subtleties of the anatomy with the tip of the needle. If, instead, the muscle is constricted, the patient is frowning and shifting with discomfort, and all sense of touch is lost to the practitioner as he or she “pushes” the needle through the taut curtain.
Wouldn’t life be grand if every buccinator was a relaxed buccinator? Well, it’s possible…. and simple too!
A few years ago I was sitting in a Yoga class, and it suddenly occurred to me that I could not relax my shoulders without also relaxing my neck, and that when the shoulders are relaxed, all of those pharyngeal and lower facial muscles are flacid as well. So I took this revelation back to work with me the next day.
We’ve all learned how to let the tension out of our shoulders, even if briefly. So I began coaching every patient, young and old, to let their shoulders “melt” just before, and during, the injection. The results were astounding, with a much higher rate of painless, and successful, mandibular blocks.
It has been my experience that seasoned practitioners as well as students learning dental anesthesia benefit from this simple modification of technique.
I am hoping that it will become an integral step in the delivery of the mandibular block, to the benefit of both our profession and the public it serves.
Dr Andrew Nette
Wolfville, Nova Scotia
Dr. Nette also teaches part-time at Dalhousie University School of Dentistry in Halifax, Nova Scotia, where the second year dental students are now learning this technique. Thanks Andrew for this great information.