Clinical Insights with Dr. Lee Ann Brady

The incidence of pulpal death following an indirect restorative procedure is approximately 13%. This number goes up to near 18% if the same tooth also had a buildup done as part of the process.

Over the years we have talked to patients about the repetitive trauma to the tooth from years of caries and dental procedures combined with the tooth’s limited ability to heal itself.

The research is clear that the largest insult to the pulpal tissue is bacteria, whether from caries introduced into the tubules during preparation, or present from a leaking temporary restoration.

Patient education, homecare and in-office recall are our best defense against caries. Gluma^® is our best defense against the bacteria we introduce into the tubules during procedures, and well fitting margins are the solution to leakage during temporization.

Evaluating the leakage is easy. When you remove the provisional to place the permanent restoration take a moment and evaluate the remaining temporary cement. If the intaglio of the temp is stained and discolored or the cement is moist and wet, leakage has occurred.

Well-fitting margins are the result of the addition of flowable to the bisacryl shell in the mouth. None of our matrices are accurate enough to hold the bisacryl against the margin during initial formation of the temp. In addition our trimming process will result in openings at the margin.

Over the years this has been a challenging technique due to the color mismatch between the temporary material and possible incompatibility. The new Venus^® Temp 2 was formulated to work with Venus Diamond^® Flow and Venus^® Flow so that margins can be sealed and temporaries repaired seamlessly.

After trimming and shaping your provisional use 50 micron aluminum oxide air abrasion around the margins. The next step is to coat the margin with iBond^® to act as an adhesive between the two layers. Leave this layer uncured. Dry the tooth thoroughly and run a ring of Venus Flow around the margins on the tooth. Seat the temporary restoration. Using a brush, blend the flowable up over the surface of the temporary and cure.

It should come as no surprise to anyone reading this article that patients want whiter teeth. I haven’t kept track of how often I hear from new patients that they would like whiter teeth when we discuss esthetics.

Even the popular press hears this when they poll readers and ask what they would like to change about their smile. So are you leveraging the power of whitening in your practice?

In a previous 360 article I talked about the power whitening has to help patients become involved in their smile and the health of their teeth. I think one of the things we forget is that most of our patients do not look forward to coming to the dentist. They are worried that they will have cavities or perio issues, wonder if they have done all they “should” have to take care of their teeth since the last visit, and then for many it is uncomfortable or anxiety producing.

Whitening is one of the few procedures we do in our office that our patients truly look forward to. If you haven’t done so already, I suggest you use the Venus White Max in-office system as a team and see for yourself the benefits. Our patients experience very little sensitivity, get incredible whitening results and love their smile after a simple hour at the office.

We are a pro whitening office. Our hygiene team takes a shade and records it in the patient chart at every hygiene visit as well as with new patients. This is an incredible way to open a conversation about whitening. We also have whitening priced so our patients can take advantage of the process, and we tell them that.

Another great idea is to offer a syringe of Venus White Pro whitening gel for patients who have taken advantage of doing in office or tray bleaching when they keep a regular recall appointment. Why not reward patients for healthy habits with a brighter whiter smile?

For many of us composite is the first and only choice as a direct restorative material today. Although realistically we all know that no restoration lasts forever, we strive for the greatest longevity and durability we can achieve. Clinical and research data support that the two most common reasons we replace a composite restoration are recurrent decay and marginal leakage.

So why should you care about the polymerization shrinkage of your composite? Simple, there is a direct linkage between the shrinkage stress of the composite and the longevity of the restoration. We have many great researchers looking at polymerization shrinkage and shrinkage stress of composite restorative materials and the impact on clinical performance. The results across these studies are consistent.

Higher shrinkage stress is associated with:

All of these factors are working against our goals and accelerate failure of the restoration clinically. There are many factors that contribute to shrinkage stress, some we have no control over, like the preparation “C” factor, which is dictated by the condition of the tooth.

Stated simply, the “C” factor is the ratio of bonded surfaces to unbounded surfaces. The greater the number of walls of the prep the composite will be bonded to in comparison to the number of unbounded surfaces the bigger a challenge polymerization shrinkage imposes. In our practices we experience this as post-operative sensitivity and marginal breakdown on Class One restorations more frequently.

We can manage the stress through utilization of placement techniques, resilient liners and light application. Most of us have learned to place composite incrementally. The science behind this is to minimize the bulk of composite, as it shrinks to the center of the mass, and overcome the “C” factor by placing increments that have the same surface area touching the prep as not.

Maybe most importantly we have control over the composite we use, and at the top of the list for how we compare materials should be an understanding of its “Shrinkage Stress.” Venus Diamond^® consistently shows low shrinkage stress in scientific evaluation. Using a material that has low shrinkage stress in combination with great technique is a sure recipe for improved clinical results.

Offering our patients options for whitening their teeth provides a high value service and opens conversations about esthetic dentistry that can ultimately lead to additional treatment. When I think back, many of my patients who have completed orthodontic treatment, veneers or replaced posterior restorations with tooth colored materials began treatment with whitening.

I want patients to see my office as a resource for whitening, whether they need information or help with at-home systems or are interested in pursuing professional treatment. I thought I’d share a few of the things we do to keep whitening top of mind in our office.

1. Energize Your Whitening Program. We make a point of displaying promotional material about Venus White Teeth Whitening Systems that we customized for our office on the Heraeus website. Move promotional materials around the office and keep them fresh. We create whitening campaigns throughout the year; celebrating special occasions can be one way to do this, such as a “brighten your smile for the holidays” campaign. This month we are letting patients know that when they whiten their teeth with Venus White, Heraeus makes a donation to support breast cancer research.

2. Offer Different Whitening Protocols. Clinically there is no difference in the efficacy of in-office whitening versus custom tray bleaching. The difference is only in the way the active ingredient is delivered and the length of time necessary to get the same results. I want to make sure I have a whitening option that meets the lifestyle and objectives of all of my patients.

3. Promote the Positive Benefits. We all have many patients who have great success stories about how whitening boosted their self-confidence. So we compile these testimonials, add before and after photos and create a whitening photo book for our waiting room. You can also create a before and after whitening gallery on your practice website.

4. Whitening as an Adjunct to Health. Carbamide Peroxide, the active ingredient in Venus White Pro, was originally used as a therapeutic treatment for patients with gingivitis. Current research supports that it reduces the bacteria in the mouth that cause caries. We discuss tray whitening with our patients as a positive adjunct to their home care regimen.

Adhesive dentistry is the mainstay of what we do, and two of the most common questions I get are about how to improve the predictability and durability of bonded procedures.

The first thing I think about when asked this question is going back to the basics to see where we can maximize bond strengths and success.

1. Are you properly storing your dentin adhesive materials? Take a look at the manufacturer’s recommendations for your dentin adhesive. Does it say “refrigeration required”? Most offices store their dentin adhesives in procedure tubs in order to make room set-up efficient, but many of these products are temperature sensitive.

2. Keep a close eye on expiration dates. We always check expiration dates when we receive product, and then make sure we use it in the order of the expiration. I have been in offices where the new product is put away in front of the old, and then when they need that older stock, it turns out it is well beyond the expiration.

3. When are you dispensing the dentin adhesive? All adhesive products contain a solvent. These solvents evaporate in the presence of air, altering the viscosity of the material. Most dental assistants I watch in the name of efficiency set out all of the materials in advance, including the dentin adhesive. Dentin adhesives should only be dispensed as they are about to be used, and discarded once they have been out in the air.

The single use systems are fabulous for this, just twist it open when you are ready to apply to the tooth. For bottles, I have my assistant take the lid off and dispense a drop directly onto the micro brush as she hands it to me.

4. Each dentin adhesive system is unique and has different instructions. Things to know about the product you use include: whether it should be shaken prior to dispensing, the recommended time the material should be applied to the tooth and the number of coats recommended.

5. What are the procedure and compatibility recommendations of the manufacturer? Not all dentin adhesives are compatible with all types of resin cements so confirm compatibility when you combine materials. The manufacturer has looked at the efficacy of the material in different clinical situations; know the procedures they recommend their product for.

iBOND Total Etch: No refrigeration required, shake or stir before using, apply 1 coat for 15 seconds, gently air dry. Surface should be visibly shiny after application, then cure for 20 seconds.

iBOND Self Etch: No refrigeration required. No shaking necessary, apply 1 coat for 20 seconds, gently air dry. Surface should be visibly shiny after application, then cure for 20 seconds.

One of the challenges of completing esthetic dental procedures is managing discolored preparations. I restore teeth on a daily basis that were at one time restored with amalgam, and have that classic greyish black color to the dentin.

In addition, managing the variety of dark brown colors that come with secondary dentin is an equal challenge. Most of our esthetic restorative materials, like composite and porcelain, tend to be translucent. The classic result when I combine a discolored prep with a translucent restorative material is a dark shadow where the underlying tooth is dark, or an entire restoration that is low in value and high in chroma.

The challenge of traditional opaque composites has been that they are high in value and don’t offer a range of chromas to match the existing dentin. With this in mind, when discolored dentin is present, I will prep away additional tooth structure to create space for the opaque layer and composite to mask it.

The final esthetics are obtained by managing the correct combination of composite shades over this layer, to get a fi nal result that matches the tooth in value, hue and chroma.

The new chromatic shades of Venus Diamond^® composite have overcome these challenges. Their masking ability in very thin layers is incredible and allows me to prepare the tooth more conservatively. The range of available chromas allows me to perfectly match the existing dentin in both value and shade.

I utilize the Venus Diamond^® chromatic shades to restore the tooth to an ideal prep shape and color. Once this layer is cured I no longer have any color issues to “manage,” and acquiring an exquisite fi nal result is as simple as if the prep were never discolored to begin with.

In addition to direct composite, this technique will allow you to achieve exquisite results when doing indirect porcelain restorations. Prior to taking final impressions mask the discolored dentin with a thin layer of the chromatic composite. At the seat appointment these small areas of composite need to be prepared with air abrasion, in addition to etching the natural tooth structure. This will ensure excellent bond strengths.

I have the good fortune to interact with dentists from around the world. We discuss the practice of dentistry, share experiences, and trade little tips that we can take back to our practices. Some of these “tips” made such a difference in what I do, they have stayed with me, and I love to share them with others. Here are five of my favorites:

1. Place a wedge interproximally as soon as the patient is numb, before beginning the prep. It can take several minutes for the PDL to be compressed and a wedge to overcome the dimension of the matrix band. This way you will see a space between the adjacent teeth, making prepping the box easier, and the contact tighter. You may have to place a larger wedge when you are ready to place the matrix.

2. Don’t dispense your dentin adhesive until you are ready to apply it. The solvent in the dentin adhesive will evaporate, changing the thickness of the material and also altering its properties, such as bond strength. If you are using a unit dose of iBOND Self Etch or Total Etch for example, don’t snap the cap until you are ready to apply.

3. Dog ear the corner of a sectional matrix to create a handle. Sectional matrix bands can be difficult to hold on to, and impossible to hold at the correct angle for placement. By bending down one corner, I create a handle that allows me not to contort my hand during placement.

4. Use Gluma Desensitizer routinely. A good friend of mine has a standard line whenever anyone mentions Gluma, “Every Prep, Every Time.” I am with him on this one, the near lack of post-op sensitivity in my practice gives me peace of mind and is an incredible internal marketing tool.

5. Take four photos on every hygiene patient that you print and give them one for their records. One of the most powerful tools for increasing case acceptance I have implemented is to have my hygienist take a full smile, retracted smile, and upper and lower occlusal photos. We take them at the beginning of the appointment, print them and give the patient a copy for their records. The hygienist instructs them that if they see anything in the photos they have a question about, to circle it and then they will ask me when I come in.

There are a few classic concerns I have when adhesively placing a composite restoration. For the first few days and weeks after the patient is in, I hope not to see their name on the schedule because they are having sensitivity.

When patients are in the office for their hygiene visits I worry about seeing discolored margins, gaps at the restoration margin, recurrent decay or fracture of the remaining tooth.

All of these “failures” are contributed to by the stress caused when composite materials shrink during polymerization. This stress causes cusps to flex and stress at the tooth/composite interface. For as long as I have been doing composites we have been talking about how to manage this clinically.

It is these clinical implications that are at the heart of my worries.

We have been striving to overcome shrinkage stress and its affects through clinical technique and material development for many years. On the technique side, we vary placement of the material, and light curing methodology in an attempt to reduce shrinkage stress. Which of these to utilize and how well they work is still being unraveled in the literature.

One theory is that we alter our clinical technique to manage the ratio between the bonded surface and unbounded surface of the material. Using this information, the technique of applying composite in thin layers became popular.

Recently we have come to understand that the mass of the material being polymerized also has an impact on micro-leakage.

Other approaches include altering the light exposure in an attempt to increase the amount of time for resin flow. Curing techniques like “soft start,” “pulse delay” and “wave” work from these theories.

Application of a layer of flowable in the base of the restoration, and newer concepts on pre-heating the composite material are also an attempt to manage shrinkage stress.

While we can continue to work from the technique side, what is clear is that working with composite materials that produce low shrinkage stress, due to their inherent chemical properties is the key to success. The inherent properties of the composite have been proven to be far more effective than any of the technique based solutions.

Class one restorations can be challenging when thinking about managing post op sensitivity and issues related to shrinkage stress. For this patient, I chose Venus Diamond composite. Following preparation, the tooth was etched, Gluma PowerGel was applied prior to the application of iBond Total Etch Dentin adhesive.

Recently following a presentation I gave on Esthetic Preparation Design, a new graduate approached me with a question. “Isn’t there a material that will let me prep conservatively and still get the esthetic results I want?” he asked. “I hate cutting off all that tooth structure.”

I knew he was hoping to hear about some great new restorative material. I had an answer he wasn’t expecting: “Absolutely. 38% Hydrogen Peroxide.”

That young dentist was asking the same question I had asked myself a few years ago before I incorporated in-office bleaching, such as Venus White Max, sometimes followed by trays at home, as part of my restorative treatment plans.

My goal is to satisfy the esthetic needs of my patients as conservatively as possible. The ideal clinical situation to meet these goals is when the teeth to be prepared are no more then two shades darker then the final restorations.

We utilize in-office bleaching as a restorative adjunct routinely. One of the first ways it brings beautiful esthetic results and being conservative together is by minimizing the number of teeth we have to prepare. A key piece of an esthetic evaluation is looking at smile zone, what teeth are visible during a full smile or natural laugh. Many patients show their premolars, and even molars in a full smile, and want to make changes to their front teeth.

If one of the patient’s goals is to brighten their smile and go lighter, and not all of the teeth need alterations in size, shape or contour, in-office bleaching goes on the treatment plan as a first step.

More complex restorative cases begin with in-office bleaching to move the existing shade of the teeth (ultimately the prep shade) as close as I can to the final restorative shade. This allows me the freedom to choose from a range of restorative materials, without being limited by their ability to mask underlying color.

Additionally it allows me to prepare the teeth conservatively with less reduction, as opaquing underlying color is often accomplished through thickness of restorative material. Lastly, it gives the ceramist immense freedom to meet our esthetic outcomes.

When I first started playing with bleaching as an adjunct to my restorative therapy, in-office was not my first line of defense. What I have found over the years is that treatment allows us to jump in and get started – and the patient sees immediate movement toward their esthetic goals.

That first appointment with the clinical assistant allows us to build our relationship and deepen the patient’s understanding of the treatment they have chosen. Also, because we need to allow 4 weeks minimum for rebound and rehydration following bleaching prior to shade selection, it streamlines the process and lets us get to the restorations efficiently.

Finally, in-office bleaching has become an incredible tool for extending the lifetime of existing conservative anterior restorations. Patients often request to have their veneers done again due to the alteration of color over time. This change is coming from the natural deepening of the dentin chroma with aging.

When we can continue to lighten that underlying color, we extend the lifespan of the dentistry and apply conservative principles over the patient’s lifetime.