Thursday, March 29, 2012

Episode 324/500: Endodontic Irrigation

Let's change things up and place the literature at the beginning.  Compliments of endoexperience.com

Comparison of the EndoVac System to Needle Irrigation of Root Canals
Effect of Apical Preparation Size and Preparation Taper on Irrigant Volume Delivered by Using Negative Pressure Irrigation System
Interaction between Sodium Hypochlorite and Chlorhexidine Gluconate

Endodontic Irrigation.  Things have changed for the better since I graduated dental school. I'm sure that irrigation tips were available long before I started dental school, but I fondly remember irrigating with one of these:



I also remember wondering if I was actually cleansing the canal system at all.  Yes, it definitely prevented a sodium hypochlorite accident (out the apex anyways).  I'm sure it didn't remove any apical filings, debris, etc. Hmmm...


Now, there are a number of irrigation needles available - and - some literature to aid in making a decision.


Essentially, there are 2 types:  Positive pressure (using a syringe), and Negative pressure (Endovac).


In the Positive pressure group, we have a classic 25-30 gauge needle w/ no side porting - something similar to this:



Then, there was a move to develop a side ported type of needle in an effort, above all things, decrease the likelihood of a sodium hypochlorite accident -  those include products such as maxiprobe and a monoject side ported needle






Finally, at the top of the food chain, there is the negative pressure (vacuum) group includes the likes of Endovac. 








Wednesday, March 28, 2012

Episode 323/500: Attached Gingiva Determination

I really didn't have an appreciation for attached gingiva before I joined the residency.  I'm really trying to remember if I ever really thought about it at all.  Oh wait (I had to go and get groceries and had some time to think about it while I listened to Wheat Belly - my brother suggested I listen to this audiobook when I was talking w/ him last night).  I did think about AG for mandibular anteriors and mainly during post orthodontic treatment and preventing increased recession.  Honestly, I didn't really understand what I was taught regarding attached gingiva.  I'm not sure I know all the answers, but, I"m a little closer.


  1. Thinking about root coverage (mucogingival surgery). AG is highly prized possession aid successful root coverage - and if you don't have it, you can gain it through a few methods. MTF (more to follow)
  2. Instead of restoring Class V Buccal lesions - why not use a connective tissue graft and a coronally placed flap?  (Root coverage) Why monkey around with a class V buccal restoration that will eventually end up leaking and possibly cause recurrent decay and increased loss of attached gingiva? MTF
Before attempting root coverage - a determination of the amount of attached gingiva is required - and -
if there is any interproximal bone loss

  1. Implant restorations - there are 2 schools of thought:  Attached gingiva is needed for implants to prevent peri implantitis and attached gingiva is not required to prevent peri implantitis.
  2. Prevention of future recession (canines are a great example)

There are a few ways to determine how much attached, keratinized gingiva you have - you can use the roll test (video) and/or the iodine test:

(Blogger, why won't you let me left justify the above paragraph?)




Tuesday, March 27, 2012

Episode 322/500: Medical Emergencies-Dr. Malamed

Several weeks ago, a medical emergency occurred in our dental clinic during office hours.  It was a basic medical emergency (we were in lecture at the time), however, medical emergency protocols were not followed.  The question then arises - did the staff know what the procedures were?  


So, we residents, have been tasked to provide basic medical emergency training to the employees in the building (maybe 50 people?).  I am reviewing seizures, and happened to come across Dr. Malamed's own site.  He is fairly well know in North America as an expert in Medical Emergencies in the dental clinic and local anesthesia.






What is neat about his website is that you can download several of his and others' articles from his website.


Preparing dental office staff members for emergencies
Preparing for medical emergencies
Basic management of medical emergencies
Buffering Local Anesthetics in Dentistry
Reversing Local Anesthesia
Permanent Nerve Damage from Inferior Alveolar Nerve Blocks
Local Anesthetics: Dentistry's Most Important Drugs
Benadryl as Local Anesthetics

Monday, March 26, 2012

Episode 321/500: Dental Composite Marketing

Just like every other product out there - you never can believe the hype.  Often, there is a swirl of activity on the internet or amongst the discussion of friends regarding a new electronic thing (iPad), movie, etc - but - what or whom do you believe?


But - dental materials?  So many advertisements for new dental materials are all over the place - it's like it's never ending.  The problem I experienced (apart from apathy towards new products), was that I didn't know what I was supposed to be looking at when it comes to material properties - and - what the literature says about it.  However, take the literature idea with a grain of salt as most new materials won't have any solid, non biased literature associated with them until the material has been in use for several years - ie - randomized double blind clinical trials.



There are several things to look at when evaluating dental materials, including the basics of directions for use, composition, comparisons to other materials, etc.  This is a really large topic, so, like eating an elephant, I'll tackle this in bits.


Here is the first bite of that big, grey, elephant.


Cheers




Ok, I was about to finish this post, but then, I just had to check out the Dyract website.  I was guided to use this material in dental school (I was (sadly) never introduced to resin modified glass ionomers....sad.)  We used this compomer to restore Class V buccal lesions.  It was terrible in many ways - to place, to finish -but - that's my own opinion (and everyone I've be mentored by....less on that..)


Here's but one line from their one of their supplier websites:


http://www.dentsply-asia.com/forum/dyract.htm


"Numerous clinical studies on compomers have shown that they are superior substitutes for dental amalgams. "


Really?  Numerous studies?  Superior?  Let's see a couple of studies before I need to sleep.


The first study shows that there is no preventative benefit by placing compomers vs amalgams.  Yes, I realize that most of the world doesn't place amalgam in kids....
Does fluoride in compomers prevent future caries in children?

This study suggests that compomers are suitable alternatives to amalgams in class I and II restorations in primary teeth.  I didn't see superior in the text in this study.
Two-year clinical evaluation of three restorative materials in primary molars


Anyways, there's lots more to follow.


Cheers





Ashley







Sunday, March 25, 2012

Episode 320/500: Dental Papilla (and forced eruption/extrusion)

\

Let's walk briefly through this case:

25 YO female presents w/ a chief complaint of: "I don't like my teeth/smile and I have lots of cavities"
History of Present Illness:  Several years of basic Emergent dentistry with little followup.
Medical Hx: No medication, no medical conditions, no allergies, no past surgical history, -ve Tob, -ve ETOH
CE: High caries risk patient, non restorable implant (#12), several edentulous spaces
Plan:  Comprehensive Case (Endo, Ortho, Fixed)

Ok.  More action, less talk.  I extruded tooth #6 (FDI #13) which brings with it the periodontium (bone, PDL).  To restore #6 with proper function (ferrule, biologic width) and esthetics - it needed to be extruded.  Crown lengthening would have had the crown margin approximately 4mm apical to the gingival margin of the adjacent teeth.  Not cool.

Here is the series of images from approximately the start to provisionals.

Initial presentation of the patient.  #4,5,6 are endodontically treated
Reverse curve of spee anyone?

#4 & 5 were recently endodontically treated. I retreated #6 following extrusion.

I provisionalzied the bicsupids w/ Fuji II (RMGI) and then set to work on #6.
I crown lengthened this region to see what the extent of the damage was from caries - before we decided to
extrude.

2mm ferrule?  Negative.
One cat skinning method to forced eruption.

.014 Niti wire, powerchain, brackets.  Bam. Extrusion was fast.


3 weeks after the above photo.  Amazingly simple.




Crown lengthening fol forced eruption. 3mm from the finish line to the osseous crest is the goal.


Yikes.  No one move.  Where'd that papilla go?
Now you've seen the photos - here's the end result.  I crown lengthened after forced eruption - I aimed to obtain 3mm of root from the finish line to the osseous crest on #6 (FDI #13).  {aka Biologic Width}.  However, this came with a price.  I knew that I may loose the papilla btn #6 and #7 - but - I remembered this article from Tarnow et al (1992).


Over the course of 6 weeks, I would re-evaluate the area (......quiet time.......the dots are for a reason), and one day, it reappeared!  I was absolutely thrilled!  I had approximately 5mm from the osseous crest to the apical portion of the interproximal contact.  According to the article above, I should have 100% papilla fill.

So, according to Tarnow and friends, with respect to the distance from the osseous crest - (aka Bone) to the interproximal contact, the papilla will be present in the following situations:

5mm: 100%
6mm: 56%
7mm: 27%

Don't forget to factor in the gingival health, tobacco use, periodontitis, etc - these will play a factor in tissue response.

The papilla is inflamed, but I'll take it.




Saturday, March 24, 2012

Episode 319/500: Composite Fiber Posts

Ah.  The fibre reinforced composite post. Let's not talk about the mechanical properties of the post itself, but about claims of their translucency and your ability to cure right to the apical tip of that post w/ your light gun - oh wait - curing light.


There are many, many, many different composite posts - all made of different materials, fibres, matrices, etc.  A great study to read regarding the ability of light to be transmitted through the post is by these folks: Goracci C, et al. Light-transmitting ability of marketed fiber posts. J dent re. 2008;s87(12)-1122:

"The concern that light intensity at the deepest level of the root canal may be insufficient to induce proper polymerization of the adhesive cement. Such a limitation would definitely affect the properties of light-cured composites, but could also influence the outcome of dual-cure cements relying mainly on light activation for curing"
 
Now, not to point anyone out, however, claims regarding optimal light transmission through their products are still out there.  


http://www.gcamerica.com/products/operatory/GC_Gradia_Core/GCA_GRADIA_CORE_Bro.pdf


In the above advertisement, these folks cite the study by Goracci et al, stating that their Gradia Core Post has  "optimal light transmission through post and core for light-curing"


But - in the study, the researchers measured the light transmission  w/ a spectrophotometer versus a radiometer.  The researchers indicated that spectrophotometry measures the amount of photons reaching different post levels were taken versus the energy of those photons at different post levels.


"Ashley, I"m going to put you in a dark room and I want you to describe the light that you will you see when I hit this button @ 2 different times"


1st time: "Yes, I can faintly see the light" 
2nd time: "Yes, now, please turn that light off, it's burning my eyes!"


Hence - yes - there was light being emitted from the apical portion of the post (GC America - check) - but - whether or not those photons had sufficient energy (or, were of the correct wavelength..) to initiate polymerization - that's another study.


Phew.  What's the point of this?  Be cautious of someone trying to sell you things - they want to sell you things and make money.


Cheers






Episode 318/500: Home Dental Lab

As I was trimming dies this afternoon in the garage, I thought to myself, "Self, why not round out the home dental lab video material w/ the lab bench".


So, that's what I did.  Here is how I am able to complete approximately 64.63% of dental lab work, at home - essentially - basic lab work that doesn't require special instruments (model trimmer, vacuum former, etc)


Cheers


Ashley






Tuesday, March 20, 2012

Episode 317/500: Greater Palatine Analgesia

A viewer was wondering how we fabricated the ice sticks for the Greater Palatine Anesthesia Technique.  


You can see the video here discussing the greater palatine ice stick "take the pain away" technique:  Greater Palatine Ice Technique

As with many things, fabrication is simple once you see it done. 
Here is the syringe:




Here is fabrication:



Sunday, March 18, 2012

Episode 316/500: Analgesics

We were given a nice little task to complete over spring break.  "Fill in this chart and hand it in"  I completed my chart, but it's a mess.  One of my fellow residents did a sweet job at inputting the required information (D McT), including dose, mechanism of action, site of metabolism, etc etc.  Thanks Dave.  I'll have this table ready for action at a moment's notice

The pill bottle from In.Saini's desk after a morning in what he calls
Prosthetics.



While I'm at it, I might was well mention a few hints regarding analgesics that Dr. Hargreaves mentioned to us a few months ago.  He is a pain researcher (and showed us his peer reviewed literature to support his claims) - therefore - I'm willing to take a shot that what he is talking about is literature supported - for the moment.  Remember, it may change.  More to follow on most of these points - each point is a post or 2.

  1. Refer to the Oxford League Table of Analgesics.  This is an AMAZING resource regarding the most up to date information on the effectiveness of analgesics and acute pain.  It is based on systematic reviews of double blind, randomized, clinical trials.  Read this if you want to be entertained regarding study design.
  2. Herpes Zoster (non inflammatory pain) - NSAIDs are ineffective.
  3. Gastric Emptying Reflex - 8oz of water - Rapid acting Motrin (gel caps) - 18 mins of onset compared to the regular onset of 2 hrs.  More to follow on this excellent tip.
  4. 30 mg of codeine is useless (see Oxford League).  The minimal useful amount is 60mg codeine = 2 x Tyl #3
  5. Pre-emptive analgesia: Prostaglandins increase the level of TTX resistant sodium channels, therefore, use NSAIDs to decrease the possible levels of TTX resistant sodium channels and aid local anesthetics for symptomatic irreversible pulpitis.



Episode 315/500: The Residency

What do the facilities look like where all this excitement takes place?  I figured I'd take some video during a quick walk around the building to show you folks what it looks like.


The building is fairly old (but it works), and consists of 2 levels.  Most of the residency treatment occurs upstairs on the second floor.  Residents slither downstairs to get beat by our OMFS mentor for one - two weeks at a time.  The beatings change depending on who the mentor is....less on that.


Upstairs, we provide treatment in bays that can occupy up to 6 residents at a time - however - there are only 9 residents in the program @ this time.  Our schedule is according to discipline - it used to be like one week of endo, one week of prostho, one week of hospital rotation - but - it varies depending on the emotional status of our assistant director (now the REAL director!).


Honestly - it's been amazing.  Our mentors have unleashed all their secrets and I feel like I've taken my professional knowledge higher than expected.


This video was taken during spring break when I had to pick up a few things to take video throughout the week.  The quietness is almost eerie - especially @ night.  Past residents roam the building, looking for an exit out of the program!


....here it is....



Friday, March 16, 2012

Episode 313/500: Suturing

Imagine:

You just finished extracting an endodontically treated 1st molar - and - you haven't extracted teeth for over 3 months.  Sweat was pouring as you tried to weasel one of those damned little roots tips out of the socket...."Don't worry ma'am, we're all done, you can uncurl your now spasming hand off the armrest".  "We just have to suture - we'll be done in 4 minutes".  You know what you're thinking...

What a liar you are.  This patient's mucosa is like tissue paper (thin biotype), and, you haven't sutured for 4 months.  The patient can't open b/c her muscles are spasming as well - and - her local anesthesia is wearing off

Why is suturing so frustrating at times. Honestly - you're simply sewing/knitting tissue together to get some great healing.  Small suture material, tongue, blood, nerves, cheeks - it all adds to the excitement of adding a few to several to many minutes to your surgical procedure.  Here are my thoughts on "almost" throwing the needle drivers to the curb when tying your throws.  It is just easier when you're out of practice.

If you're willing to try using your hands alone to tie a surgeon's square knot - skip to the second video.

If you're like the rest of us - check out the first one.

Let me know what you think.

Ashley




Wednesday, March 14, 2012

Episode 314/500: Dental Curing Lights - Maybe something you didn't know?

Curing lights....I remember listening to a new graduate 4 years ago talking about his research on curing lights.  I was like, "oh man, I'd better check that our curing light - it's like 10 years old..."


4 years and many discussions about curing lights later - I wanted to share what I have been shown over the past few years.  Main points:



  1. Check the power density (mW/cm2).  2 things that can decrease the output are: cured composite on the light table, scratched/old light guide (old school QTH).

  1. Type of photoinitiator in your composite.  If it doesn't fall within the range of light (nm) produced by your curing light (LEDs are narrow spectrum) - it's like trying to wash paint brushes coated in oil based paints with soap and water - it just isn't going to work.

  1. Depth of Cure:  The literature is replete with articles discussing the topic of depth of cure.  Marketeers are bringing back "deep curing" - 4mm or greater deep....I"ve been trained to not believe this - however - the world was flat at one time......I don't have any data - but - if you're unsure...try this, MTF (more to follow)



Fibre Reinforced Posts - Light curing through them.....or not.


Tuesday, March 13, 2012

Episode 312/500: Immediate Denture

Dr. Dray wanted to discuss briefly the management of Aaron, his immediate denture patient.  He finished waxing up the immediate provisional acrylic partial dentures on his lab bench and talks about the path forward.  (I swear that he's saying "from the spaceship" at the beginning, but it's not :(  )


http://www.allthingsdentistry.com/2012/03/immediate-dentures.html



This is a great case for learning as we can see how a prosthodontist tackles fairly difficult cases such as these, and more importantly, the thought processes involved.


I have included his lecture pdf here:





Sunday, March 11, 2012

Episode 311/500: Calcium Hydroxide

I remember when this was starting to become an intracanal medicament.  I was in 3rd dental school, and I had heard something about using it (from a colleague) between endodontic appointments.  I remember mixing CaOH powder from the bottle and trying to cram it into a canal.  That was painful.


CaOH in all its beauty




Now, we have all sorts of neat tips and things to aid placing this material.  Is it the best antimicrobial out there for inter appointment canal disenfection?  Who really knows.  The literature is replete with articles discussing the benefits, such as: (Properties and applications of calcium hydroxide in endodontics and dental traumatology) and the "it's not that good" (Antimicrobial effects of calcium hydroxide and chlorhexidine on Enterococcus faecalis)




http://www.theendoblog.com/2009/12/calcium-hydroxide-as-intercanal.html
A great point that a recently learned this past year was to take into consideration a few factors when reading literature articles discussing 1 or 2 micro-organisms.  For the past few years, e.faecalis has been the bad kid on the block with regards to a bacteria that is difficult to eliminate from the root canal system and is touted to be THE CAUSE of endodontic failures b/c it is found often in apical periodontitis Enterococcus faecalis – the root canal survivor and ‘star’ in posttreatment disease.  Think about this:






1.  What if 8/10 times, you attempted to give a mandibular block, you failed to achieve local anesthesia.  You couldn't understand, but you know, that generally speaking in the literature,it's normal to miss a block 8/10 times.  Ok, no big deal.  But, what if you have been doing this anesthesia technique entirely wrong - and - it's only by fluke that you've been achieving minimal block anesthesia?  Has anyone really watched you provide local anesthesia after your first few "successful" blocks in dental school?  Have you ever had a number of experienced clinicians critique you on a daily basis about your block technique. (if you have, stop reading now.)  Here's my point:




e.facaelis SEM


Maybe e.faecalis is a commensal bacteria, and has absolutely NOTHING to do with endodontic failures, post treatment disease, etc.  But, it is always there, hanging out and multiplying when the conditions for its growth are right - much like those kids at 7-11 when I was growing up (I'm from a really really small town).  This argument states that perhaps we haven't been able to cultivate the EXACT microoganism/viruses/ things, that are actually responsible flareups, endodontic failures, etc.  What if the organism(s) were a virus?  HIV is a virus and can cause some fairly awful side effects.....


2.  I compare this idea of e.faecalis to global warming.  We all know that something is causing climate change (if you don't believe, stop here.)  Most likely it's a myriad of reasons, but one exact reason is not it.  It's probably every single idea that people have come up with and more (CO2, Nitrogen, etc etc) or the fact that there are 7 billion humans on earth (imagine all the heat production from our bodies alone)....sorry for the rant.


e.faecalis Macro Photo?




3.  Imagine you have to bake cookies for your kids to take to school tomorrow - and - you don't have a recipe.  What do you do?  Go and buy some.  Exactly.  Now imagine, you have to publish, or complete some research, and have a deadline to meet (you haven't started yet).  What do you do?  Go buy some?  Not exactly, but if you can take the RECIPE to grow a known bad bacteria, do some quick invitro testing, and bam - get out of there - life is good.  Just imagine the hassle of trying to cultivate something you don't know is there and don't know what medium to grow it on (if it will survive on any of the media we have today).....Therefore, this argument is stating that a number of articles are leapfrogging on others (with good intentions), but, the real mystery bug(s) are still lurking...


4.  I could be entirely wrong.....


Let me know your thoughts.


http://www.dentistrylearningnetwork.com/discussion/17/is-e.faecalis-really-that-bads






Saturday, March 10, 2012

Episode 310/500: FAGD and ABGD

I need to really thank my wife.  She helped me prepare for the FAGD and ABGD written exams that I just completed yesterday.  Thanks Kath, I love you.


  I was hesitant to post about these board exams, but, if it clears up what exactly these things are for 1 person, it's worth it.


I'm in an Advanced Education in General Dentistry 2 year residency. What does that mean?  Good question.  I'm still not sure of the exact position that I'm supposed to be in, however, I can tell you that I have learned more now than I have ever learned.  In dental school, I was young and foolish - I just wanted to pass and get out.  14 years later (since the start of dental school), I feel that I can really start to get a handle on the even the basics of dentistry.  That is so damned cliche, but, it's true.  


Much of what we were taught in dental school, for good reason, is cook book. "Do it this way, don't stray out of these lanes, and you'll be safe".  I've half thrown the cookbook out and now look to the literature to see what evidence supports my clinical decisions - it's paid off in several ways - more on that later.


So, in an effort to show something for my 2 years of dealing with Dr. Saini,  we are guided to take the board examinations for the American Board of General Dentistry (ABGD).  I had no idea this existed before I entered into the residency.  There are 3 parts - a written examination, and upon passing the written examination, you are eligible to take oral boards and present 2 cases (complete treatment) to another board.  Damned, that's a lot of boards.


FAGD - Fellow of the American Board of General Dentistry.  In a similar theme, I had no idea what this was about before I started the residency - I'm hoping that my lack of knowledge of these 2 organizations is b/c I"m Canadian...?  It's a written examination, along with completion of CE.  I think we get 300hrs of CE for the residency. I"ll embed this next sentence in the middle of a paragraph that no-one will read!  The FAGD examination - honestly - I completed b/c I was studying for the ABGD exams and decided to hit 2 birds with one stone.  Bam.  I at least hit the FAGD exam bird, I won't know for a while about the ABGD exam.  It was.....tough.


Why did I choose this track?  I love being a Jack of all trades - can you not tell?  As well, I've spent the last 10 years of my career trying my best to hone other skills (leadership-if you know me, I know you're laughing at this point..., administration, AOC, plsc, etc etc)  It was time to fire up the professional education.  


This has been beyond my expectations.


Is it my intention to get you thinking about post graduate training.  Perhaps. What I really want is to build a community of folks that ask questions about materials, techniques - beyond what is learned in throwaway journals - and beyond what one expert says. I'm no expert - what I show can be null and void tomorrow.  Nothing is forever - and - everything is controversial - dental amalgam, composites, climate change, global warming, all on 4 dentures, is recycling useful, etc - See what the world is talking about and not just one person.  Did I just null and void myself?


Post comments here:


http://www.dentistrylearningnetwork.com/


Awesome.


Ashley

Thursday, March 8, 2012

Episode 309/500: Upcoming topics

During my study time, I've been thinking of some ideas to blog about.  I apologize that the content has been pretty slow over the past few weeks, but, I must pass my board exams...it's like they never end.  Here is a small collection of ideas that I have been mulling over while cramming my brain full of data to answer questions such as:


2. Glass ionomers consist of an ion-leachable aluminosilicate glass powder and a phosphoric acid liquid. Carboxylic acid groups (-COOH) chemically bond to calcium on exposed tooth surface.
a. Both statements are true.
b. Both statements are false.
c. The first statement is true and the second statement is false. 

d. The first statement is false and the second statement is true. 


The answer is d.  The acid is polyacrylic acid.

1.  Restoring Class V's - Why restore when you can coronally position the gingiva?  CT graft or alloderm (or whatever you want) instead of placing that unesthetic restoration.  For carious lesions, abfractions, abrasions - place the gingiva coronally which is much more esthetic and easier to perform (for the most part) than those painful to isolate Class V restorations.  This is an absolutely great hint that was provided to us during a periodontal lecture - 2 days worth.




2.  Open Sandwich Technique - if you don't know what I'm talking about, don't fret - I had no idea 2 years ago either.  I've completed a fairly thorough lit review and opinion review and I'm excited to share this fairly important idea.  It involves class II composite restorations placed deep deep in a proximal box.  So deep, that the floor is in cementum.  Do Dentin Bonding Agents bond to cementum?






3.  How to review the literature - the basics. Looking at what is important when you read an article.  We spend a lot of time discussing current (and classic) literature.  In my previous life, I only truly read the free journals - you know - Dentistry Today, Oral Health, etc - these are also known as "throwaway journals".  Indeed there are some neat ideas in those articles (perhaps my blog is a throwaway blog?), however, often, these articles can't be compared to peer reviewed literature articles.....and even then...
..I'm definitely kicking the door in with this one.....I just pulled this article (I was trying to find some pictures), which is discussing composite placement.....bulk fill, flowable liner under composite?  We'll use this article to discuss what the literature actually says....basics...I'm not a rocket scientist.










4. Extractions.  We've watched and listened to Dr. Partridge talk about extractions.  I"ve thought about video recording extractions, but, usually, the handpiece is in the way, and it's an overall difficult to learn from experience.  Could there be a better way to convey his message? More to follow.


5.  So, you have an endodontically treated tooth and you want to place an adhesively retained post.  Ever thought about the sealer affecting the bond strength?  Eugenol is the liquid of Roth's.  "oh"  What about using NaOCl during cleaning and shaping and it's affect on bond strength?  NaOCl removed your collagen from the canal walls..."oh".  My fibre post can transmit the light of my curing light to the apex of the canal to cure the apical portion of my resin cement.  It can't effectively.."oh".  More on this topic.


If you have some ideas, please send them my way.
ashley@allthingsdentistry.com

Wednesday, March 7, 2012

Episode 308/500: Amalgam Repair

I'm still confused about posterior restorative materials.  Yes, the world is going towards composite restorations for almost everything.  However, it's not happening exactly at this moment. (I realize some countries have banned amalgam for decades)  Yes, amalgam is a bad word - however - it wasn't always.


But what about repairing those old amalgams (and composites for that matter)? I've OFTEN wondered about repairing those old amalgams that look like they should not be repairable, but, I fail to see any signs (clinically and radiographically) of decay.  Yes, I know there are many many more factors involved in repairing restorations (economic, dental school requirements, patient wishes). 


I'll be honest. I read over and over how patient's esthetic perceptions these days are higher than ever.  Really?  I'd have to agree that with respect to the maxillary anterior 6 teeth (maybe up to the first bicsupids), esthetic demands are high(er).  However, for 80% of folks, what they care most about is cost and not having to go back to the dentist every 2 years to have restorations replaced.  I dread having to be treated by my colleagues.  That's the reason I became a dentist - to try to make a small difference in treating folks.  I still dread treatment, however. 


Ok, no video (it will soon come), however, in light of studying for boards, I finally came across this interesting article that I read a few years ago and lost.  It's about amalgam repair - and - your eyes and perceptions.  Is it hard science - no.  But..just gives a perspective, like http://www.farnamstreetblog.com/


View more documents from Ashley Mark.



Tuesday, March 6, 2012

Episode 307/500: Endodontic Shift Shot


SLOB


It seems so easy to do. Just angle the xray head a little mesial and or distal and bam - there's your shift.  Oh really?


How many times have I had difficulty in getting a clear shift? Often enough. I am no means an expert in clinical radiography techniques and look to experts when in time of need.


I needed


He responded.  He = our resident endodontic mentor, Dr. "no refined carbs for 30 days"


I was having difficulty in obtaining a clear shift shot and he suggested using a hedstrom file in one of the canals to aid in determining which canal was what.


No way.


Yes way - it's that simple.  No bending the file, moving the stopper, etc to change the appearance of one.  It worked and I was able to confirm WL before initiating cleaning and shaping (rotary endodontics).


Cheers


Ashley






k file, endo file, endodontic file, hedstrom, dental radiograph, k file radiograph
Pretend this is a bicuspid w/ a palatal and facial canal


k file, endo file, endodontic file, hedstrom, dental radiograph, k file radiograph
There's my shift, but sometimes, I have difficulty determining one
canal from the other (ie which canal is which?)

k file, endo file, endodontic file, hedstrom, dental radiograph, k file radiograph
Change one out for a different file (hedstrom)
and life is zenlike perhaps?

k file, endo file, endodontic file, hedstrom, dental radiograph, k file radiograph
A simple radiographic comparison (Kfile vs Hedstrom)


Episode 306/500: Oral Surgery Instrumentation (Exodontia)

More often than not, our training out of dental school is fairly....weak...regarding some of the basic clinical requirements.  Perhaps it has something to do with learning waay too many other things in such a short span of time - maybe not.  I"m not sure.


What I am sure, is that even for me today, simple discussions with other clinicians help significantly - including instrument names.  Oral surgery instruments can be confusing and overwhelming.  If you're not using them everyday, you will forget their names if you have little experience with them.  If you've never been introduced to other instruments, perhaps you'll never know that there are others available.


That was the #15 scaler for me in this setup.  That little guy really is a "6th finger" during exodontia procedures - allowing me to detect PDL, bone, cementum, dentin.  Dr. P really showed me this trick.









This is what the tip is supposed to look like

This is a well used example of a 15 scaler





For the my resident colleagues (non Canadian, it appears) - it's the 77R elevator.  It's dog legged (I'm still unsure what that really means..) and has serrations. A great instrument.


77 R Elevator




77 R Elevator




Ashley



Sunday, March 4, 2012

Episode 305/500: Thinning Bite Registration Material

9 times out of 10, we use Blue Mousse (or some addition silicone/elastomeric material) as the Interocclusal Record material of choice.  It's easy.  We use addition silicones (PVS/VPS) for "almost" anything requiring some sort of impression or record.


 Ask a seasoned dentist which "other" impression materials they have used, and it's like listening to the story of recorded audio.  "Remember, LPs? 8 tracks? cassette tapes? CDs?"  Yes, it's the old timers that natter on about polysulfide rubber base, condensation silicones, polyether, ZOE paste (wash in complete dentures) - and worse - it's the old timers that still write those damned exams that force me to remember those old materials......less on that another time.  We all remember the properties of materials once we use them - we don't use anything other than essentially addition silicone (PVS) - let the other stuff go.  
   Yes, polyether is great for some instances of multiple implant impressions and dentures - but - I compare  keeping those "one of's" materials to holding a complete kit of Panavia ready for use.....it expires before it's all used. (unless you use Panavia for everything, please disregard this comparison)


I apologize for my rant.  If it's not the High Noble gold content I'm memorizing, it's the eruption sequence and root formation timings of the permanent dentition - along with - the AAE recommendations for tooth trauma (luxations and avulsion). Here's a good one:




The absence of which layer of dentin predisposes it to internal resorption by cells present in the pulp?
A. Mantle dentin
B. Circumpulpaldentin 

C. Predentin
D. Secondary dentin
E. Tertiarydentin 




  Blue Mouse - It's an addition silicone, (PVS/VPS) and it can be found in the Classic set version (2 mins) or Super Fast - 45 seconds.  Nice.  According to this article in 1994 Differential accuracy of elastomeric recording materials and associated weight change., any of these elastomeric products have excellent dimensional stability.  This is nice b/e often a wafer of wax distorts, and, if you can't hand articulate the casts..your mounting will be off.


I was taught (and I just read in Schillingburg and Summit), that it's key to shave the interocclusal record down a point where you are able to verify your mounting.  Dr. Dray mentions here, that there is another reason why we need to shave these babies down.  I had no idea.


Cheers


Ashley