Whitening has turned into a billion dollar market in less than five years and its popularity crosses both sexes.  It’s that feeling one has when one is showing off the “bells and whistles” of their new car. It is fashionable, they feel and look great, so why not show off that bright, celebrity smile.

Bonding more commonly known as tooth-colored fillings can alter the shape or close spaces between teeth. 

Porcelain veneer is probably the talk of the young and restless. This thin coat of enamel-like porcelain bonded directly to the surface of front teeth. The finished product can dramatically change the shape, size, color and position of one’s teeth. 

Crowns somewhat less pricy, also referred to as caps are an alternative to veneers when a tooth’s structure is missing. 

Implants are now on the continuing education budget of most dentists as they develop the skill of replacing missing teeth but without having to reduce adjacent teeth.  This gives you an overview of how the practice of dentistry has transitioned from the days of drill and fill to highly clinically skilled surgeons who practice on the one part of our anatomy that is firstly seen by our family and friends.   

However these standards do not come cheaply. Which reminds me of the lyrics attributed to George Wiedner…“when an irresistible force meets an immoveable object”, in dentistry this is called “burn out”. This leads me into my segue. By far, the subject of anesthesiology attracts the largest audience of readers to websites and blogs on a world wide basis. Pain is still by a long shot (no pun intended) the main concern associated with any visit to a dental office. In spite of every aspect of the new décor and facilities that have been intentionally designed to reflect a much more relaxed, serene and contemporary environment, the nemesis of fear still ligers. Dentists (GP’s) are rushed to maintain the high standards associated with the main revenue generators of their practices while staying as close as possible to their schedule.

It is just not humanly possible to maintain all areas. Ironically it is the delivery of the local anesthetics that pays the price. I will credit my lay readers with the following terminologies because their comments make for interesting conversation at cocktail parties. Let me be the first to admit that my brother also practices dentistry and I would not in any way be discourteous to these dedicated and skilled clinicians. I hope my observations will be taken it in the way it was intended. However I am hearing terms like haematoma, swelling of the venous plexus, trismus, necrosis, facial paralysis, and even more recently terms like unexplained paresthesia occurring after a non invasive procedure.  Questions and blogs relating to local anesthesia, out number other problems in dentistry by as least three to one.  Ironically  it remains the main reason why most people do not look forward to a visit with the dentist. 

According to Malamed’s Handbook on Local anesthesia, the rate of delivery should be at 1ml per minute. In other words the injection should take about 1.5 minutes to be properly given. The latest survey of dentists across North America is between 19 and 25 seconds and mostly as a bolus. My notes on Pharmacodynamics  would seem to lend credibility to  George Wiedner’s lyrics where “an irresistible force meets an immoveable object”. The end result is a clash between the pH of the tissue (7.4) and the pH of the local at (3.5) mostly delivered as a bolus after bone has been touched. Most of the RN base molecules are destroyed extracellularly (outside of the myelin sheath) resulting in too few base molecules crossing the sheath to effect or block sodium transport.   

The situation is compounded when there is an extra layer of fatty tissue around the sheath or a build up of lactic acid as in the case of bruxism or grinders. Getting back to the classic reasons for local anesthesia failure, the thiophene is dynamic to the benzene molecule which superceded it by some thirty five years in Canada. It is just one of these developments whereby a forward thinking company decided to invest some venture capital; I am the first to admit that pharmaceutical companies have not come up with much since 1947 when Lidocaine was introduced. Some academics strongly feel that the addition of the more lipophilic molecule, the  thiophene, may slightly increase the aromatic moity due to its spherical shape.

It has been observed Malamed 3^rd Ed that the anesthesia produced by a standard dose of  any local anesthesia will vary to a great extent between different persons…(more to follow on these five classic reason for failure.) The duration of action may vary between a few minuits to up to an hour. Thinking “within the box’, here are the five basic reasons for failure:

From anecdotal reports, it would appears that once the classic litmus test has been performed and failure to achieve the expected quality of anesthesia is still less than adequate to the patient or you,  the onus is then shifted to other excuses. In my 25 years of investigating complaints, I would be hard pressed to count on the fingers of one hand the numbers of truly defective products which were as a result of the manufacturer). 

The manufacturing process is so regulated that a total batch of local anesthetics would suffer the same biological analysis and would involve a total recall and subsequent disposal.  Both FDA and Canada will not ship fine pharmaceticals (or finished produced) if they have not met North Amreican standards. To support this check list, it is standard procedure for companies to donate goodwill products to be used by dentists who willingly give of their time, to work long hours in condition that are less than adequate and often not safe. These dentists must be commended.  There are numerous files of “thank you” letters and a willingness to revisit to see the fruits of their labor and the beautiful smiles of these young people. There has never been a mention of quality control deficits or any special requests for products not in standard production in the North American market. You may well say “never look a gift horse in the mouth”. These are all North American trained and practicing clinicians who have a strong desire to share their expertise with less fortunate people.

In the pharmaceutical world there is a constant evolution of drugs and their indications. Many of you may not have been around when Metronidazole was first introduced for vaginal infections, back in the sixties. Since then it has been used successfully as an antabuse-like drug for alcoholism. Today it is probably one of the most frequently prescribed compounds by peridontists.

Nothing is constant. As Albert Einstein said…E=mc2.

The object is to leave you with a solution and possible and update to the age old reasons for anesthetics failure. Obviously our population is growing and the numbers of patients visiting dentist are on the increase; it therefore stands to reason that untoward incidents will follow. However I do strongly feel that pharmacodynamics needs to factored in. Delivered at the rate of 1ml/ml, if per chance a muscle or artery is slightly nicked the response from the patient would give you ample corrective time measures to avoid a dirty trismus or some other situation that eats into your time and a patient that is not too happy. So the question is whether the saving 50 seconds is worth it? 

For any dentist(s) who are willing to take this challenge, (must be timed), I will visit an Eastern location (say NY) without an honararium. I will also demonstrate a didactic on never having to give a traditional nasopalatine injection. Finally, as a bonus I will demonstrate the techniques for bone (pulpal) anesthesia known as Mandibular Infiltration.(Drs. Aaron Dudkiewicz and Stephhane Sshwartz Journal of Canada Dent Association No.1 1987). I am sure any dealer would be be eager to grab an opportunty like this. the lecture is about 3 hours.    

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Haynes Darlington M.Sc. PharmD.

Then there is the experimental phase of drugs, whereby longitudinal studies do reveal new indication for drugs that never existed when they were first investigated. Aspirin is the obvious one that keeps going and going and going.

This article is limited to dental procedures and the drugs, which may be necessary to complete a procedure. If per chance the local anesthetic is deposited as little as one MM off the intended target, The response can produce results that are as equally scary for the patient as it is for the dentist. The fundamental response can be traced to the base or foundation of one’s every day management of stress. The “flight or fight” response, originally discovered by Harvard physiologist Walter Cannon in (1915) where the hormone adrenaline or epinephrine is secreted endogenously to produce the physiologically normal response to cope with any potentially stressful situation.

 What are the saber tooth tigers of today and why are they so dangerous?Fortunately,

in our modern world we are not exposed to foraging for our daily sustenance, as did the cave man. However our hormones cannot determine the origin of stress and do respond in exactly the same way as did our fore parents.When we experience excessive stress, whether from internal worry or perceived external discomfort, bodily reaction can be triggered and can be organic or psychogenic.Nerve cells firing will activate the well known chemicals adrenaline (epinephrine). Sympathetic Nervous System (SNS) is a branch of our autonomic nervous system. It is always active at a basal level called sympathetic tone and becomes more active during times of stress. In other words, stress is the condition that results when our environment transactions lead us to perceive a variance, whether real or not, between the demands of a situation and the resources available to us, whether they be real (biological or psychological).

Today, however, most of the saber tooth (no pun intended) tigers we encounter are not a threat to our physical survival. Today’s saber tooth tigers consist of rush hour traffic, single parent management, missing a deadline, bouncing a check or having an argument with our spouse. Nonetheless, these modern day episodes trigger the same adrenaline release. Road rage, is relatively new, but is a classic example of how powerful and alive is our autonomic nervous system. Homeostasis must be maintained at all times and our autononic nervous system will go to all extent to see that perfect condition is mainained and stable.When one has not been keeping regular visits with their dentist, there is a basic guilt that is inscribed in one’s brain. For most of us, it started during childhood. It was that nightly ritual…“have you brushed your teeth?. This question has attained, some degree of noterity status in western society. For example the book, The fairy tooth godmother where an exchange for something that has lost its usefulness (such as a tooth) for something of everlasting value carries significant personal values and  stays with one, even after one has flown the coup.

The body’s defences start to produce more endogenous epinephrine to balance the perceived threat of pain and the personal guilt that accompanies these situations.Ironicly, the drug (local anesthetic) which the dentist most likely will be using contains epinephrine. My earlier example of how therapeutic substances can produce more than one effect; dependant of how and where that drug is administered could not be relevant  than as in this scenario. The dentist needs to deposit the local anesthetic to bathe the nerve in such a way that it restricts or blocks any sensory impulses. This is called vasoconstriction. It restricts the flow of blood in that specific area allowing the patient to be comfortable and without sensation of pain.

Let us for the sake of comparison, see the effect of what would have been the result if the same drug had been administered into the vessel. The same drug would have affected vasodilatation  or the opposite desired effect. The experienced dentist has anatomical landmarks which more or less reduces any accidental error. The indent here is not to enter clinical diagnosis, but rather to raise the profile of pharmacodynamics in a world of ever changing medications.

 As clinicians have found it necessary to specialize, I for see the day for specialized pharmacists. The complexity of structural algorithm of compounds is already exceeding our capacity.Comments to

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Have you ever been told by your dentist, “Gee! I seem to be off today! I cannot get you fully frozen”. There are many techniques to deposit local anesthetic into the oral cavity (tissue of the mouth) however, for this discussion; I will only deal with two basic modes, namely infiltration and complete nerve block.

Infiltration allows the dentist to freeze one or two teeth at one sitting, whereas the nerve block freezes a complete quadrant. For dental purposes the mouth is divided into four quadrants, to facilitate the numbering (of the teeth) process. Whether one is given an infiltration or a block, the desired expectation for the dentist is the same. He/she needs to be able to complete the procedure without the patient feeling no more than the initial gloved fingers of the dentist. In other words, that area of the patient’s mouth should feel like a piece of log. It is referred to as the “wooden effect” and dentists call this “class A” anesthesia.

However, according to all textbooks on dental anesthesia, failure is generally accepted to be around 15%. There are some 15 to 18 people out of 100 who will still have residual sensation, or in other words, will experience some discomfort and or pain. When this situation occurs, dentists will chat among themselves as to the reason(s) why. Discussion of marijuana comes later in the text.There are many reasons listed, ranging from a bad batch of anesthetic solution to persons who may be classified as having accessory innervations. There could also be patients with anatomical variations, such as a wide flaring mandible and furthermore, the explanations could be an infection within the gum tissue. There are several more reasons, for example too rapid a delivery of the solution, or even an over anxious patient. These all add up to give us that 15% failure.

However, our changing lifestyles and habits are beginning to become a thorn in the sides of dentists. The growing use of cannabis…known on the street as marijuana, is being associated with the inability to achieve local anesthesia in some patients. The duration of action of local anesthetics depends primarily on the redistribution of the drug away from the site of action. This redistribution can be altered by several factors, some of which also influence onset. These considerations include diffusion away from the site, concentration, lipid solubility and protein binding qualities. This recreational habit is no longer an experimental phase of a growing youngster. It is now widespread among all walks of society.

Dentists have never had to deal with this variable factor back in the sixties and seventies. However, before he/she starts the “marinating” process, this is when the dentist deposits several different brands of anesthetic solution in numerousareas of the mouth, hoping to strike luck. But this luck is seldom achievable.

There is a small window with which the dentist has to play. If anesthesia is not apparent within that time, then the tissue has become too acidic and another attempt can be made later when the pH of the tissue has settled down somewhat. Contrary to popular beliefs, the administration of a “cocktail” anesthetic concoction offers very little, if at all any pharmacological advantages.   Patients using cocaine should allow at lease twenty four hours, if a dental visit would involve the use of epinephrine (present in anesthetic solutions). The interaction of these two substances can cause a rise in blood pressure as well as a change in heart rhythm.

The explanation of this phenomenon (marijuana) can be answered pharmacologically. Smokers of marijuana trigger high liver enzyme activity, which is known to hasten the breakdown (metabolism) of the local anesthetics. This results in a situation of not being able to sustain profound anesthesia.

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Suggested References
Haas DA. Localized complications from local anaesthesia. Journal of the California Dental Association 1998 26:677-81.
Haas DA. Drugs in dentistry. In: Canadian Pharmacists Association. Compendium of pharmaceuticals and specialties. Ottawa: CPA, 2002, L51-54.

I was entering my sophomore year of engineering. This transition year would be taking me from broad-based general education to a more highly-focused mechanical engineering course through advanced studies in mathematics, science and systems. By all measurements, I was well positioned with my peers and my grades were above average. My freshman year was now over and I was literally pacing myself for the complexity of projects which eventually would see my skills put into practice. At this stage in my studies, I was like a sponge in the ocean soaking up all and every lecture I attended. Being pulled and pushed with every movement of the tide around me. No clear route was calculated on my internal GPS; however there was a steady wind which seemed to be pushing me on a definite course. Or so it appeared to me.

It was difficult to conceal my identity; I was from a small Midwestern town and attended a private high school with my siblings where we enjoyed a comfortable life as children of parents who were both professionals. My mother was a restorative hygienist and my dad, Dr. Watson, owned a well established dental practice. I was now off campus and was fortunate to share a modest third story attic-like apartment with Steven, a student who was also in engineering, one year ahead of me. Our apartment was no more than 500 sq.ft. of living space but comfortable and spotlessly clean, with a clear view across town where one could see the familiar Golden arches and where many a university kid caught up on notes, while enjoying the special burger of the day. Steven was no exception. He loved to eat at the MacDonald’s; He was hooked on their Big Mac and ate there at least four or five tines a week. Our apartment consisted of a sitting area, a kitchen, a washroom and one bedroom with two single beds. I was beginning to feel more in charge of my life and free to come and go as I wanted. My room mate was friendly but somewhat quiet and deep within his thoughts, or so it appeared to me.

Our schedules were quite different, and we did not have a lot of time together other than the occasional small talk while having a coffee. We were not big on booze but enjoyed the odd beer. He had a part time job at a small computer repair store and would be home usually by midnight. The tempo and the anonymity of the North East were very fascinating and everyday I could feel maturity was seeping into every move I made. I was at ease with myself and happy, especially when I heard from my folks. Although it was never overtly pushed on me, the atmosphere at home during high school was subtlety an expectation of going on to undergraduate school in the East. I was the oldest of my siblings and now that I can reflect, both my parents were lovingly using me as their flagship.  “If Jim sets the pace, the others will follow”. I was fortunate in that I did not have to work during my semesters away from home. My mother saw to that. There were to be no excuses for failing grades. I lacked for nothing. However in no way was I pretentious. In fact I was often seen and not heard. Deep within me I knew I was popular albeit, shy. I was no “Brad Pitt”, but confident was I, or so it appeared to me.

It was during our second semester of my sophomore year that I started to have some concern about my room mate. He suffered from bruxism, commonly known as grinding of the teeth, typically accompanied by the clenching of the jaw. It is an oral Para functional activity which is common in many humans. Bruxism  (Wiki) is caused by the activation of reflex chewing activity; it is not a learned habit. Through osmosis, I had picked up many dental terminologies over the years from both of my parents. This condition (grinding) was not unknown to me; however the situation was causing me restless nights. I talked to my dad during one of our weekly “how are you” conversations and he suggested that Steven should see a local dentist, because of possibly damage to his teeth. It was not difficult to share my concern with Steven, because his girlfriend also thought he should see a dentist. We (Steven, his girlfriend Veronica and I) had now become much closer. Steven opened up a bit more and at times could be quite comical. I was seeing the other side of him. We started to hang out on a more regular basis. Steven had appreciated my father’s professional advice and did in fact go to see a dentist associated to our engineering faculty. The diagnosis was confirmed. There was some small initial damage which had started to erode the enamel of his molars.

Gloss phobia, more commonly called the fear of public speaking, is thought to be the most common of all phobias. As many as 75 percent of all people are afraid to speak in front of an audience. Without going in to all phobias and their rankings, my observation is that needle phobia in the dental office is by no means abnormal and ranks up there among the highest. Dentists still have to work around needle phobia. However, the future looks encouraging with the first FDA approved needle free anesthesia product for scaling and root planing.

This story is about my friend Sergio and his wife Lina. They were the perfect couple. Lina was a bit trendier, but by no means could one describe her as “the flavor of the day”. She had the smarts, and a solid head for business, probably groomed by her father who, like many Italians emigrated from Italy to find their fortune in the Western world, the land of opportunity. Sergio and Lina were comfortably set. They were off to a good start after their wedding, with the help of her dad and family, pretty well owned their first home sooner than most of their friends.

Lina had been pressuring Sergio to get some cosmetic work done on his teeth. The daily espresso coffees and his mother’s blueberry pies were beginning to test the strength of a solid Roman Catholic marriage. Lina’s desire to pop an impromptu kiss on Sergio was starting to wane because of his discolored teeth. She wondered how can “I persuade him at least, to go for a dental check-up”? Her goal for Sergio was to have his teeth cosmetically improved to show off the fashionable celebrity white-teeth-smile and nothing was going to stop her.

The whitening of teeth has become a billion-dollar business and celebrities have had no small part in raising the bar for the perfect smile. Another cosmetic fashion statement which is showing its colors is the art of tattooing one’s body parts. I mentioned this purposely, because a visit to the tattooing studio is far more popular that a visit to the dentist, although, ironically there is a common factor, namely pain. Why is this?

Why is it that people will pay huge sums of after-tax dollars to have a tattoo sculptured in sensitive parts of the anatomy and yet be hesitant to visit the dentist? Maybe vanity is more powerful than oral health! Or maybe the School of Body Art has out-marketed the college of dentistry?

How often have you seen a young woman/man flashing a tattoo, but in need of obvious orthodontic or other dental work?  We have to rely on anecdotal reports in the absence of a truly scientific study.

Back to my friends Sergio and Lina. Researchers have come to the rescue with a product that brings effective needle-free anesthesia for patients during scaling and/or root planing procedures. Oraqix fits the perfect scenario for a patient who is needle phobic. This product is the first FDA approved system for the above indications. Hopefully this addition to dental armamentarium will allay the fear of the dreaded needle.

Fear of finding other latent problems incurring a cost is an irrational decision. Why should one have two standards for maintaining perfect health?  Oral health is no less important that physical health. The diagnosis of oral cancer is by far more often seen by the dentist than by medical doctors. If for no other reason it makes good sense to keep the oral cavity healthy and free of possible terminal diseases.

Four out of five Americans claim a desire for whiter teeth. Never before have so many options been available. Nu-pro is a dentist prescribed take-home system that has been designed to address the patient’s tooth whitening requirements and offers two formulations with dramatic results in one to two weeks. Who are the best candidates for do-it-yourself whiteners?

Before you spend a dime on whitening your smile, your dentist will explain what is best for you and the reason why. Teeth should be healthy without cavities or recession of the gums thereby exposing sensitive root structure.  If whitening agents come in contact with an open area on a tooth with a clear path to the nerve center of your tooth, you won’t care what color your teeth are because they will have to peel you off the ceiling.

You need to have a proper evaluation by your dentist.   A talk to your dentist will determine if you do have tooth discoloration and what is the cause. There are two major ways teeth become discolored. Teeth naturally discolor as we age, and we all have lighter or darker teeth, just as we have different complexions. Everyday habits and food consumption penetrate the tooth’s enamel to cause extrinsic and intrinsic stains: There are as many reasons for tooth discoloration as there are solutions.

Over-the-counter whitening doesn’t work if the discoloration comes from an injury to a tooth, for example. Also, if you have teeth that have tooth-colored fillings or crowns that are dark or discolored, again, over-the-counter whiteners do not whiten porcelain or tooth colored filling materials.  Stains can be caused by foods such as coffee, tea, red wine, and nicotine. Rule of thumb, if it stains your carpet, it can stain your teeth.

What kind of results can we expect from an over-the-counter product? Today Over-the-counter whitening products work differently and better than ever before because the technology has changed so dramatically. Will your teeth look as different as if you had full mouth veneers? No. But if you have a pretty smile, that you want whiter and brighter, the newest over-the-counter options are very effective.

Here’s a look at some of the latest options.  Most people hate the messy trays you stick in your mouth. What are the alternatives? Crest White strips, night effects (liquid strip gel). Crest White strips continue to be the OTC gold standard in whitening — and a beauty secret for millions of Americans, (mostly women). When you look in dressing cabinets, you see them right next to the lipsticks.

Whiter teeth give women confidence and make them look younger and prettier. A great new whitening product is hitting store shelves now. It’s called Night Effects and it’s very exciting because it works while you sleep. The first generation products made to whiten teeth while we sleep included a tray and stuff oozing out of it. I dare you to sleep with that unit in your mouth and not destroy your bed linen. Bearing in mind that these are all Over-the-counter products.

Dental prescribed take-home products are still the most effective. So what has been improved for the OTC shopper? Night Effects is great for a couple of reasons: First, it’s good for people whom for whatever reason, cannot whiten during the day. Second, the coating sticks to your teeth. You’ve heard me say that for a product to work, the whitening agent has to stay in contact with the teeth. The problem with some of the other over-the-counter products is that they tend to quickly wash away when they come in contact with saliva, food or drink.

Night Effects appears to be the first paint-on product to address this problem. The patent process they use is as follows. Immediately after applying the gel, the product forms a liquid strip coating that stays on your teeth overnight. The liquid strip slowly releases the whitening ingredient into your teeth to remove stains and loosen stain-causing build-up. In the morning, you simply brush the liquid strip coating and stains away.

Researchers have overcome the overnight challenge by developing a silicon-based gel applied with a brush. Secondly, it is not water soluble like other paint-on products. Because of this new technology, the whitening gel stays on your teeth for hours while you sleep.  Over-the-counter whitening serves a selected market, however for the clinically accepted procedures, it is best to have your dentist involved.

Comments to author. mailto:localanesthetics@yahoo.ca“  M.Sc. PharmD. CCPE   Please visit WWW.AnestheticsNews.com