The truth can be hard to face: Something is wrong with the design of these provisionals … We may be working on a broken provisional and feel the deep frustration that comes with knowing something went awry.

I challenge you, in these moments, to reframe the ‘problem’ as a mystery to be solved. You are the clinical detective who needs to work backwards a la Sherlock Holmes to figure out ‘whodunit.’

Mystery of the Broken Anterior Provisional

Remaking and adjusting an anterior provisional from the upper right to the upper left canine (for the second time) is a horror story in the making. Before you allow that narrative to take over and call the lab to have them rush the case back, remember to rely on your intuition and technical expertise.

You may not be able to call the lab because you haven’t taken final impressions. Either way, let the provisionals tell you what the flaw in the design is, rather than believe you can run the solution show.

A good first place to look and listen for answers is the occlusion. For example, if the patient reports that they wake up with headaches after you’ve placed the provisionals, you would want to look closely at envelope of fucntion. Is the patient heavy on the centrals and laterals? If so, you can begin the process of adjusting.

Methods of the Dental Detective

As you examine the issue, you may find other clues, such as that the patient is catching on the incisal edge in their return stroke from protrusive. You continue to adjust, beveling edges for a smoother transition. You leave the guidance shared between the canines and centrals, keep it smooth, but even this doesn’t stop the patient from breaking the provisional.

If you’ve ever seen or read a good detective story, you know this isn’t the time to quit. When things seem most opaque, the detective is usually at a breaking point where the parts might finally start to fit together. Once they do this, the flood gates open and they rush toward the explanation.

You will reach this point while adjusting again. In response to what you’ve learned, you begin to shallow the patient’s guidance and share protrusive with the premolars. You decide to shorten lower anteriors and increase overjet by proclining the restoration. Here, you’ve come to the solution. You need to work it out on an articulator perhaps and then go back to the mouth.

The main lesson is that we have the most to learn from cases that don’t go perfectly. Plus, it would get pretty boring if there were no dental mysteries left to solve …

We have a remarkable heritage at Pankey. Around the 1950’s and 1960’s, four innovations converged to permanently change the dental profession worldwide. Pankey dentists were part of the creation of all of them.

In my last post, I talked about the invention of the sit-down chair. Now, I’ll dive into time and motion studies, high speed air-driven rotary handpieces, and the “washed-field’ evacuation technique. These innovations had a significant impact on the future of dentistry.

Pankey Innovators of Modern Dentistry

Time and Motion Studies

These studies evaluated and changed how dentistry was delivered, e.g. four-handed dentistry, ergonomics, efficiency, etc. My father, Dr. John Anderson was a large part of that along with men from the east coast. Don Coburn from Canada was also a major time and motion researcher and later became a strong supporter of the Institute. My dad wrote several articles in the Dental Clinics of North America about office design related to time/motion principles.

High Speed Air-Driven Rotary Handpieces

Before the 1960’s, belt driven handpieces were the norm. Dr. Henry Tanner was at Bethesda at that time working with engineers designing this new high-speed technology. This too was reluctantly received by the profession at first but now one can’t imagine doing dentistry without it. Dr. Tanner was on the faculty at the Institute and you can find his portrait in Master’s Hall.

“Washed-field” Evacuation Technique

This is the type of high volume vacuum system we use each and every day today. It replaced the workhorse cuspidors used by everyone in the 50’s and early 60’s. The new water-cooled high-speeds needed this innovation for pulpal health and prepping efficiency. To my surprise, there are still cuspidors being used in operatories to this day. Elbert Thompson of Salt Lake City, Utah was the dentist that created a consumer friendly system of high volume evacuation. He was a friend of Dr. Pankey and an integral associate of these other innovators.

What Pankey history do you admire? We’d love to hear from you in the comments! 

Click Here for When Ceramic Debonds: Part 1

A Methodical Process for Examining the Frustrating Reasons Behind Why

One of the most disheartening and emotionally upsetting situations is when a ceramic restoration debonds. Our ability to act constructively in the moment is key to our future case success.

In Part 1 of this series, I explained why it’s important to acknowledge your frustration without letting it control you. I also outlined the beginning of a methodical thought process that will help you figure out why ceramic debonds.

The following steps assume you’ve already looked at the resin and determined if the ceramic was prepared, cleaned, or conditioned properly.

Completing Your Investigative Process When Ceramic Debonds

You have a different set of explanations for what happened if all of the resin cement is on the ceramic and the tooth is clean.

Clean the tooth thoroughly to remove all trace of the temporary cement. The issue may have occurred when the enamel and dentin were etched, regardless of whether you used a total etch or a self etch technique.

Next, ask yourself about the amount of enamel you have versus the amount of dentin. This involves taking a second look at the prep, because secondary dentin can be quite problematic when bonding.

Another area you may need to reconsider is your technique for dentin adhesive. Did you accurately follow the steps? Could poor isolation have led to a contaminated tooth during the process?

Lastly, sometimes there is some resin on the tooth and some on the ceramic. In this case when resin is in both places, you can benefit from rethinking the occlusal forces on the tooth and the functional design. Your patient may have higher functional risk or you might have lacked complete precision while adjusting the final occlusion. A good clue that you’ll find resin on the tooth and the ceramic is if it fails under load.

You can better target your problem solving and decrease the risk of the same technical issue recurring in the future by identifying where the resin is located. Follow the thought process in this series and you’re well on your way to smoother cases.

How do you respond when ceramic debonds? Please let us know your thoughts in the comments!

Methodical Process for Examining the Frustrating Causes

Dentistry is not solely a clinical, emotionless skillset that uses techniques to achieve outcomes. It’s also emotional, fraught with the normal human frustrations of mistakes and complications. One of the situations where I see this most frequently is when a ceramic restoration debonds.

Acknowledging and Embracing Our Emotions When Ceramic Debonds

On an average day at the dental practice, we experience the full range of human emotions: happiness, curiosity, boredom, excitement, frustration, etc. But sometimes, this is interrupted by a situation that becomes far more dramatic.

Ceramic that debonds creates a highly disconcerting scenario. It makes us feel powerless and consequently we find it difficult to resolve the issue with the full spectrum of our scientific learning.

Before we can return to ourselves and work toward a resolution, we have to acknowledge that it’s okay to be human! You cannot outrun trouble and messiness. When ceramic debonds, you’re upset and the patient is upset. The confluence of these factors leads to the struggle of regaining control over your brain’s analytic functions.

Having a plan for these types of situations, a methodical set of steps to take and questions to answer amidst the blinders of upset can help you carry out the task at hand.

Questions to Ask During a Methodical Ceramic Process

There are two initial queries in our method for sleuthing out the cause when ceramic debonds. First, we ask why the ceramic restoration came off and how we can minimize or eliminate the possibility of it occurring again.

We must also then ask: Where is the resin cement?

The process for discovering this involves examining the tooth and the internal surfaces of the ceramic through the lenses of our dental loupes. Attempting to visualize the resin is ineffective compared to scratching the surface using an explorer.

If we’ve completed this test, finding that all of the resin is attached to the tooth and a clean ceramic interface, we proceed to the next step. We must consider the process of bonding to the ceramic and whether or not the ceramic was adequately prepared.

Dental ceramics can have many different preparation requirements depending on the type. They can have different etching times, distinctive percentages of hydrofluoric acid, or can require preparation with air abrasion. Oil secreted from hands, in addition to blood, saliva, die stone, or try in paste, could have contaminated the ceramic. If it wasn’t cleaned properly, the result was marred. One step where problems are more likely is when ceramic is conditioned with silane or Monobond Plus…

You can learn about other causes in the upcoming second installment of Dr. Brady’s ‘Why Ceramic Debonds’ series. How do you feel when you face this problem? Please leave your thoughts in the comments!

How an Extra Dental Assistant Can Improve Your Protocol for Restorations

Restorations and adhesive dentistry have rapidly advanced over the past few decades. Changes in materials necessitate corresponding changes in protocol. Read on to learn the adjustment that drastically improved Dr. Mike Crete’s bonding process.

30 Years of Significant Advances in Clinical Dentistry

I have been practicing for a little over 30 years and often find myself looking back amazed at how many advances have occurred in clinical dentistry. Dental school requirements were focused on metal restorations that were either: (1) condensed into place (amalgam and gold foil) with “retention form” the key to success, or (2) cemented with the likes of zinc phosphate. Ah, the good ‘ol days of mixing on a cool glass slab!

My favorite general advancement over the years has been the concept of adhesive dentistry.  Not a day goes by in my practice where I don’t either bond a direct composite, bond a crown or two, or place an entire arch of bonded porcelain veneers.

Why 4-Handed Dentistry Fell Short for My Restorations

I must admit when I first started placing bonded restorations I was gun shy and felt like I would never be as adept as I was at carving amalgams or burnishing exquisite gold margins. I fumbled through bonded porcelain and composite like it was the same as metal restorations. I had mastered working with one chairside assistant. I could almost do dentistry blindfolded and 4-handed dentistry made me look great.

After about 3 years of really not liking treatment that involved bonding and finding myself justifying in my head how amalgam and gold were better, I finally had an aha moment when a mentor told me, ”You can’t do something new the old way.” I was a bit puzzled and asked, ”Why not?” My colleague then introduced me to the concept of 6-handed bonding.

6-Handed Dentistry Makes For a Better Bonding Protocol

Every time I do either a single unit or multiple indirect bonded restorations, I utilize both a chairside assistant and a “tray-side” or tertiary dental assistant. The tertiary assistant has the 5th and 6th hands.

The tertiary assistant helps by efficiently preparing the restorations for bonding (cleaning, silane, etch, prime, bond, resin adhesive, etc.) while the chairside assistant helps me keep the teeth isolated, etch the teeth, and place the restorations with precision and a very high level of accuracy. The chairside assistant can be totally focused on me and the patient, while the tertiary assistant prepares and hands me the indirect restorations.

Consider modifying your protocol to include a 3rd pair of hands and make 6-handed bonding part of your daily routine.

What is the most significant change in clinical dentistry you’ve noticed over the years? We’d love to hear from you in the comments!

One Easy Method That Will Increase Restoration Accuracy by Customizing An Articulator to the Actual Angle of the Eminence

When we rely too heavily on ‘assumptions’ to determine the angle of the eminence during a restoration, we risk creating a faulty end result for a significant amount of patients.

About 80-85% of patients will not present an issue. You can set the angle of the condylar path on the articulator, basing your efforts on a design assumption that most patients have an eminence with a steeper angle. The lab creates posterior disclusion on the articulator and there is equal or greater disclusion.

Problems arise when you end up with a patient who falls into one of two eminence categories.

Two Types of Patients Who Need Customization to the Angle of the Eminence

For 15-20% of the patients you treat, customization is necessary. These patients often fall into two categories:

1. Eminence is flatter than the assumption.

The restorations did not touch on the articulator, yet you’ll have to remove posterior differences chairside in these patients.

1. Eminence is steeper than the assumption.

These patients tend to experience less chewing efficiency. They complain that bits of snack food pack onto their restorations. This packing occurs on the occlusal table.

In both cases, a solution is needed. Creating posterior excursive disclusion or interferences relies on how well the angle of the eminence works with the angle of the anterior guidance. To achieve great results for patients outside the norm, there are two options.

How a Photograph Can Enable Restoration Customization

Accuracy is the ultimate goal for final restorations. Many dentists who find themselves dealing with a patient in the less common eminence percentile decide to take a protrusive bite record. My advice is to choose an alternative option that requires less effort.

The easier way also uses a semi-adjustable articulator. You still customize the articulator to match the patient’s actual angle of eminence. But instead of the protrusive bite record, send the lab an end-to-end retracted photograph.

For this image:

• The incisors should rest on the incisal edges.
• The second molars should be visible and in focus.

The lab can use this image to create posterior disclusion. They simply dial the condylar setting to match the photograph and use a sharpie to record it on the model.

What method do you prefer for customizing the articulator? We’d love to hear from you in the comments!

Why You Should Determine Value Before Chroma and Hue When Matching Shades for Composites

The true artistry of the dental profession tends to show itself in many of the more challenging requirements of cosmetic dentistry. One of these areas where we can express our esthetic skills is in shade matching for composites. The struggle arises in understanding the various properties of natural-looking teeth and determining what visual aspects to match first.

 Composites 101: Defining ‘Shades’ and Their Components

Before you can begin to choose which aspects of a natural ‘shade’ to preference, it’s integral to delve into the nature of these complex components.

Reflectiveness and translucence combined determine the appearance of a tooth. Reflective properties are especially important for shade matching because this is the true definition of ‘value.’ Value tends to be defined as the coloring on a range of white to grey, but it’s actually a measure of tooth reflectiveness.

Other esthetic qualities of dentin and enamel include ‘chroma’ and ‘hue.’ A classic numeric scale of 1 (lowest) to 4 (highest) is used to judge chroma, which simply refers to the intensity of a color. Hue, on the other hand, is generally deconstructed into the letters A, B, C, and D. These indicate the names of color.

‘Shade’ is simply the end result when all three parameters of value, intensity, and hue are viewed together. The key lesson here is that these parameters must be matched separately. To achieve the best case outcome, you must rank them according to importance.

Should You Shade Match for Value, Chroma, or Hue First?

This is where things get tricky and we start to juggle multiple considerations at once.

Layering is paramount because dentin shades and light properties differ in composites versus real dentin. This is also true for enamel shades. Added to these differences is the fact that dentin and enamel do not have the same amounts of reflectiveness and translucence. Basically, you have dentin and enamel discrepancies between composites and real teeth in addition to the discrepancies that exist between dentin and enamel.

Precision will impact the final appearance of the tooth, so it’s important that you layer composites to get around these discrepancies. The composite materials selected should match for value before chroma and chroma before hue. Because final value is a blend of the individual values of every composite layer, you must consider that each layer is not going to be representative of your intended value. They build on one another to create life-like reflectiveness and translucency.

A Method You Can Use for Determining Value in Composites

My favorite method for constructing an esthetically superior value is to start the appointment with layering. I plan what composite shades I want to combine ahead of time and work efficiently so that inevitable teeth dehydration doesn’t affect my results.

I layer the materials on the labial of the adjacent tooth in their final thicknesses and photograph the outcome. This allows me to see if my chosen combinations match my esthetic goals and troubleshoot if the composite doesn’t disappear against the tooth. When I’m not happy with the look, I easily pop the composite off the tooth and re-do the process. I only begin to contemplate chroma and hue once I’ve matched the value.

How do you troubleshoot shade matching issues in your esthetic cases? We’d love to hear your perspective in the comments!