As John F. Kennedy once said: “Things do not happen. Things are made to happen.”
This was the case for a seminar that HANSAmed had the privilege of sponsoring this past February.
There has been controversy regarding the safety of articaine for mandibular blocks. A philosophical line has been drawn in the sand of the dental arena separating the dentists for and against these claims. These two sides have been primarily spearheaded by the publications, comments and lectures of two well-known experts in the field of dental anesthesia: Dr. Stanley Malamed and Dr. Daniel Haas.
The event called “Local Anesthesia: What’s New and What’s Controversial” was presented by the University of Toronto and the Toronto Academy of Dentistry with an unrestricted educational grant from HANSAmed Limited.
The event was quickly sold out, and the quality of the discussion certainly turned out to be what the audience of around 200 dentists expected.
The morning portion of the session focused on the pharmacology, alternative techniques and developments in dental anesthesia. What followed was a friendly debate between Dr. Malamed and Haas.
Dr. Haas argued that, based on his studies, there was a correlation between articaine's higher concentration and paresthesia after mandibular blocks.
Dr. Malamed argued in turn that:
· If articaine is really neurotoxic, why is it that 95% of the reported cases are in the mandible when ½ of all dental care is in the upper arch?
· There are no reported cases when Gow-Gates or Vazirani-Akinosi block techniques are used since they bypass the lingual nerve.
· If articaine is used in other fields such as ophthalmology, orthopaedic and plastic surgery, why are there no reported paresthesia incidents in literature for these fields?
· He highlighted an article by MA Pogrel that estimated paresthesia incidents at 1:26,762… BEFORE the introduction of articaine to the USA, explaining that “the mechanisms are unknown and there is no prevention or treatment.”
· That in Germany, articaine was introduced in 1976 and has captured 90-95% of the market.
· That similar claims in Denmark had to do with the “Weber effect” which explains how the number of reported adverse reactions for a drug rises immediately after it is launched into a market. (Reports in Denmark have decreased dramatically since the Pharnacovigilance Committee of the European Union determined that there was no basis for strengthening the warnings for using articaine).
· He explained that, according to another article by MA Pogrel demonstrated that the proportion of paresthesia reports for articaine and lidocaine matched their usage. There was “no disproportionate nerve involvement from articaine”.
· Dr. Malamed also demonstrated how, even if the claims against articaine were accurate, the risk is as small (according to Dr Haas’ papers 1:400,000 in Ontario and 1:4,159,848 in the USA) as that for being struck by lightning (1:750,000 in the USA).
· He concluded that “IMHO… if it’s the lingual nerve… it’s MECHANICAL not CHEMICAL.”
The seminar came to an end with this understanding; articaine is safe. There is no concrete scientific proof that articaine causes paresthesias. However, if you as a dentist have concerns and do not feel comfortable using it then you don't have to.
All in all, it was a very successful seminar that brought a lot more clarity to the subject and certainly put many minds at ease. We want to thank everyone at U of T and the TAD who were involved in making this event happen, and Dr. Stanley Malamed and Dr. Daniel Haas for sharing their knowledge, and to all the attendees for taking the time off their busy schedules to be present.
