Bite Point

Corrosion Explosion

In "Amalgam, Politicians and all the Pink Trees" I briefly reviewed the historical and scientific history of dental amalgam, the ever-controversial restorative material that contains silver, copper and mercury in its modern formulations.  At the present time the science indicates that, since a person's mercury exposure in the course of a day from silver amalgam fillings is between 1/10 and 1/100 of the total we receive from air, water and certain foods, then there are no serious concerns about mercury toxicity.  (And that's if you have a lot of them in your mouth.)  Keep in mind the crowded, industrialized society that many of us live in; mercury is given off in various forms from diverse industries, particularly in power generation from coal.

(It's all a trade-off, isn't it?  I mean, I'm glad that this computer is running for me whenever I want it...)

Anyway as I sign and have patients sign these ridiculous forms from the City of Philadelphia, forms that explain "choice" in dental restorative materials and are really an anti-amalgam crusaders' Machiavellian tactic, I get to thinking on a daily basis how we need to talk about the other aspects of these metal nettles.  You see, we don't place them in our office anymore for other, more enlightened reasons.  Meaning: technology has provided us with better alternatives.  For one, gold foil preceded dental amalgam, at least in the U.S.  I understand that Paul Revere placed gold foil restorations during the time that he dabbled in dentistry.  Composite resins had initial challenges but among us Composite Cognoscenti it's well known that these materials were refined into excellence in the late 1980's, and with the latest "self-etching primers" we can treat teeth in ways that remind us of Arthur C. Clarke's line that "Any sufficiently advanced technology is indistinguishable from magic."

Yet so many insist that amalgam lasts longer than composite resin, all things being nearly-equal.  Well, I removed an old amalgam today, most recent in a long line of these little beasties, one with decay under it.  Statistics are more important than anecdotal observations of course, but photos are so very visceral...  So I took a shot of an amalgam in one of my staff (which we will be replacing shortly), then of the piece of material that I removed from my patient.

Amalgam does not bond to a tooth per se, but it seals- and it does this by corrosion.  Little by little the corrosion occurs.  It reaches the optimal point in about 2 years after placement.  After that, it's all downhill.  Yes, composite resins have their issues too.  There's incomplete hybridization and collapse of the collagen net and transudation...  But we can control all of that to an astonishing degree these days and it's only going to get better.  Amalgam hasn't gotten significantly better since the manufacturers took the tin out and replaced it with copper in the 1970's.  Anyway have a go at the corroded margins, or edges:

But this is my fav- like some kind of CSI-Amalgam officer, I removed a large piece en masse, polished the outer layer for comparison to clean metal, and photographed the inside of the material, the part that was up against the (decayed) inside of our patient's tooth:

 

The silver turns pretty thoroughly black, doesn't it?  Yah, it's time for these things to go by the wayside.  Recall- it's technology from 1833, with an eight, and that's being generous.  We have better now.  Yet- there's no dental or medical reason to remove dental amalgam restorations that are relatively new and functioning well, with no breakdown.  It all depends on how they're doing. 

Watch Out! Washout!

There are many reasons to replace a missing tooth. Function, appearance, comfortable chewing, stability of the rest of your teeth... There are two main ways to replace a tooth without having anything removable- bridges and dental implants.

Bridges involve placing crowns on the teeth adjacent to the missing one and building a series of connected crowns together:

(These are presumably the teeth of a vegetarian.)

The teeth that have the gold insides are "abutments", the ones that are cemented onto the patient's actual teeeth. The teeth that are all smooth porcelain are "pontics", the ones that bridge the gap between the patient's real teeth.  (This is the same root word as in "pontiff" and "pontoon".)

Implants on the other hand are titanium structures that are designed to replace the very roots of teeth; here's an X-ray of one of my favorite successes:

And the finished case;  It's astonishing considering how much damage there was to his jawbone beforehand:

The list of pros and cons that arises in choosing implants versus bridges is a long one indeed.  Individualized discussion bewteen you and your dentist is a must.  In this post though, I wish to point out what I perceive as the most serious drawback of a dental bridge: cement washout and recurrent cavities.  Here's the progression of events:

-The human jaw and particularly the lower jaw flexes as we chew.  Much like those skyscrapers that sway a few feet at the top in the wind, the bone flexes as our muscles act on it. 

-This has a far-reaching implication.  We dentists are always aiming to create the perfect margin (fit at the edge), trying to buy the perfect cement, striving to create the ideal occlusion- but in spite of all our efforts, the very foundation is slippin' and slidin' right underneath our treatment.

-Usually the cement in the tooth farther back gets affected first and cracks and dissolves out:

 
See the cement in the one, and the bare metal in the other?

-In our sugar-laden society, cavities usually ensue.  The whole shebang might need to be redone, although we often can rebuild the tooth underneath and save the (expensive) bridge.

-Worst for me on an emotional level is that since the cement is often still strong on the for'ard tooth, to use the nautical term, we have to tap out the bridge.  Even with the best auto-tapper on the planet, a kosher one designed by a couple of Israeli dentist brothers now residing in New York City, this is waay stressful on our patients.  I'm not even going to show a picture of the device.  And there's a very significant risk of breaking said innocent for'ard tooth.  No, I don't like tapping on people, not one little bit.

The upshot is, in the decision matrix between these two restorative choices, bridges can suffer decay in spite of the excellence that we dentists strive for.  And: one A-list candidate for the inscription on my tombstone is: "Titanium doesn't get cavities".

  

Angela Lussier's "The Anti-Resume Revolution"

More on topics that are not in the molar section of the Venn diagram, but my friend Angela Lussier has written an important book.  The value in social connectivity is well demonstrated by the very fact that I know Angela in the first place, and also by the manner in which any patient of ours here in Philly could benefit from her work in tangible ways.  In pre-Internet times none of these valuable connections between us would have occurred- at least not without a lot more effort and searching.

Here then is the cover:

 

And here Angela introduces her work:

The saying goes that necessity is the mother of invention. I say frustration is the mother of inspiration, especially for people who know they aren’t getting all that they want out of their lives. The Anti-Résumé Revolution is leading the shift in the way people apply for jobs, start businesses, view their futures, and create what they want in their life.

Are you tuning out of your life in order to get through each day? Or, are you living an authentic life? Do you even know the difference? Are you facing a changing world that no longer looks and sounds like the one you once knew? Now that you’ve come up for air and graduated, come back to the workforce after raising your kids, or received the dreaded pink slip, what do you see in your future?

If you know you deserve to be happy and have the job you dreamed of as a kid, you are ready to become part of the revolution. Within the pages of this book, you’ll learn how to create a personal brand for yourself online and in the face to face marketplace. Find out the most common mistakes made by job seekers and how to avoid them to get what you want, faster. Learn the #1 way to be remembered by anyone you meet and read inspiring stories from the people who created the life they want and are currently doing what they love. If you’re looking for a meaningful change in your life, this book is for you.

By purchasing this book, you are committing to be part of the shift from mindlessness to meaningfulness. Are you ready to restart your life on purpose?

If not today, when?

 
As we close let's have a look at a review:

“If you are looking for a refreshingly down-to-earth, practical, yet highly inspirational guide to managing your career, look no further than ‘The Anti-Resume Revolution.’ Angela Lussier knows her stuff, shares her hard-won knowledge, and shows you how to take control of your career and your life. Not for the lazy or timid, her ideas require more than passive online job searching but promise enormous rewards: a satisfying life doing work you love and a strong support system wherever your career takes you.” -Louise Kursmark, Master Resume Writer, President of Best Impression Career Services, and author of 20+ books on resume writing and career management

Tom Bentley on Commas

Quite possibly I shouldn't stray too far from topics related to oral health. Quite possibly I should strive for tight focus, nothing irrelevant.

But there are no Blog Police. And until there are, let's let writer extraordinaire Tom Bentley riff on commas:

"Ahh, yes, commas let you roll the flavor of a sentence around your tongue, preventing the sentence juices from being swallowed before their time. They are like genial traffic cops, corralling conflicts with clauses, preventing squabbles between jostling nouns, pointing out an opening in a sentence that was being squeezed. Commas believe in justice."

And:

"Rick, I can be comma happy myself, because I like to command (or fantasize command) over the rhythm of a sentence, and commas are little waves of the conductor's baton. You do have to watch those stray punctuation marks—like commas and periods—straying outside their quotation mark gates: they belong inside."

http://www.tombentley.com

 

And as if that weren't enough to think about:

"By the way, the semicolon is truly the formal gentleman of punctuation (top hat and all), but I'll go into that another time..."

Solidarity

Somehow, this picture taken in the Negev desert best captures the essence of my daughter Amanda's recent trip to Israel. 

Solidarity. Human beings standing together in the face of the awesome power that Nature (still) has over us.

Whether the challenge to be faced is a vast desert or a tiny germ- or a foolish government or an uncaring corporation- we do our best when we connect in the way that this picture teaches us.

NicVAX

Only 5% of smokers started when they were over 18 years of age.

Five percent.

Teens are encouraged to try smoking through peer pressure, other social pressures and Big Tobacco advertising.  The sad fact is that a high proportion of people who try cigarettes (or chewing tobacco) will become physically addicted to nicotine.  Malcolm X, 1965: "Cigarettes are more difficult to quit than heroin".

We've all heard the numbers, but just in case you need a refresher:

-On average- ignoring the outliers- if you smoke, you can take 22 years off your life.

-50% of cancers are attributable to smoking.

-84% of lung cancer is attributable to smoking.

-30% of heart disease is attributable to smoking.

-80% of bronchitis and emphysema are attributable to smoking.

-75% of oral cancer is attributable to smoking.

And these are all conservative estimates.  While there are a number of toxic substances in tobacco smoke that sound scary even to a non-chemist- hydrogen cyanide, carbon monoxide, nitrosamines, free radicals and oxidizing gases- it's the nicotine that's highly addictive.  It's a gestalt, really- the mythical power of holding fire in your hand, the social advantage of having something cool to do with your hands, and then the actual physical power that nicotine gains over the user.

And nicotine is such a simple molecule:

 

There is now a new strategy for smoking prevention and cessation.  Nabi pharmaceuticals have developed a vaccine against nicotine which is in FDA fast track trial phase. 

From their website:

Nicotine is a small molecule that upon inhalation into the body quickly passes into the bloodstream and subsequently reaches the brain by crossing the blood-brain barrier. Once in the brain, the nicotine binds to specific nicotine receptors, which results in the release of stimulants, such as dopamine, providing the smoker with a positive sensation, which causes addiction. NicVAX is designed to stimulate the immune system to produce antibodies that bind to nicotine in the bloodstream and prevent it from crossing the blood-brain barrier and entering the brain. Therefore, the brain does not produce the positive-sensation stimulants as a response to nicotine. Pre-clinical animal studies with NicVAX have shown that vaccination could prevent nicotine from reaching the brain blocking the effects of nicotine, including effects that can lead to addiction or can reinforce and maintain addiction.

Nicotine addiction is difficult to treat effectively. We believe NicVAX has advantages over existing treatment therapies because its effect is irreversible for potentially six to 12 months following vaccination as antibodies to nicotine continue to be produced by the body?s immune system. This is important due to the extremely high relapse rate that has been observed when a smoker attempts to quit smoking. Currently, smokers being treated for nicotine addiction can stop using their therapy and resume their addiction.

http://www.nabi.com/

This drug may turn out to be highly effective in helping smokers quit the habit.  NicVAX also has potential to reduce the catastrophe of teens who first try smoking to satisfy some fleeting need of the moment and end up getting brutally tricked by Big Tobacco into an addiction that's almost impossible to break.

 

 

Here is Nabi's informational pdf:

http://www.nabi.com/images/factsheets/fsNicVAX.pdf

And the Wikipedia article is updated periodically regarding approval status:

http://en.wikipedia.org/wiki/NicVAX