By Lee Ann Brady, DMD 

When a crown comes off and we are going to put it back in the mouth, we need to remove the old resin cement that is inside the crown. What is the best way to go about this? 

First, we need to know if the crown is made of zirconia or lithium disilicate. If you have a radiograph of that restoration, you can tell immediately which one of those two things it is. If you don’t, you can always attempt to X-ray it. (That’s what I do.) Alternatively, you can assume the crown is made of lithium disilicate, which is the more technique-sensitive material when it comes to removing cement. 

For crowns confirmed to be zirconia, employing 30-micron aluminum oxide air abrasion effectively clears out the old resin cement. Subsequently, re-etching the inside of the zirconia prepares it for reseating. For crowns presumed to be lithium disilicate, this approach should be avoided to prevent crack propagation. 

In the case of lithium disilicate crowns, two alternative methods can be employed: 

1. The crown can be placed in a porcelain oven to liquefy and evaporate the old resin. However, caution must be exercised to avoid rapid heating of the hydrated ceramic that has been in the oral environment. Rapid dehydration will introduce cracks and lead to crown fracturing. 

1. An alternative method involves using a brown silicone point in a high-speed handpiece, adjusted to lowest speed. A brown silicone point at slow speed effectively removes resin without damaging ceramic. 

How will you know when all the resin has been removed? When etching lithium disilicate, whether using red 5% hydrofluoric acid or Monobond Etch & Prime from Ivoclar Vivadent, any remaining resin will be evident because the dye sticks to it after the etching solution is rinsed off.  

By Lee Ann Brady, DMD 

For addressing the access hole of a screw-retained implant crown, my preferred method involves applying Teflon tape over the hole followed by temporary filling material, such as Telio Inlay from Ivoclar Vivadent. 

I emphasize to patients the importance of maintaining accessibility to the screw for potential adjustments without jeopardizing the integrity of the ceramic crown. Hence, immediately after seating the crown, I ensure no adjustments are needed before doing the filling. 

Patients are scheduled for a final post-op appointment with the surgeon after the restoration is in place. If there are no issues requiring crown removal, the Teflon tape and Telio Inlay may remain indefinitely, monitored during hygiene recall appointments. As long as the temporary filling remains intact, replacement is unnecessary. 

In cases where the Telio Inlay dislodges but the Teflon tape remains intact, I inform the patient of our plan to reapply the temporary filling. However, if repeated dislodgment occurs, leading to inconvenience, we consider transitioning to a permanent filling. In such instances, fresh Teflon tape is applied, and the access hole is filled with composite that precisely matches the crown’s color. 

Even if years pass and the Telio Inlay needs replacement, I opt for a temporary filling for ease of identification if removal is necessary. Only if frequent filling replacements prove bothersome do I consider switching to a permanent filling because I prioritize easy retrievability of the screw. 

Gary M. DeWood, DDS, MS 

Many dentists believe that provisional restorations don’t really matter. After all, they are not really a stand-in for the final restoration. I would respectfully disagree. I am a proponent of creating functional, durable, and highly esthetic provisional restorations, every time. They have the potential to impact your dental practice a lot more than you might think. Whether you print them, form them, or free-hand them, a GREAT temporary is a great billboard for your practice. 

1. Make the provisional as Esthetic as the final restoration.

I contend that the more your provisionals look like what you are hoping for when you seat the final restorations, the more people will talk about them, AND you. 

I was able to build a referral restorative practice by creating provisionals that made patients want to come to my practice and specialists want to send people. For much of our career, almost the entire team of the oral surgery office we worked with, and many of the team members from the other specialty practices we worked with, were our patients in Pemberville, Ohio. 

Front teeth or back teeth, when you make them look like teeth, people will like it and they will show and tell other people. “This is just the temporary?!” was not an uncommon question or exclamation from our patients.  

2. A GREAT guide makes a GREAT provisional restoration.

Your wax-up** cast/model serves as your vision, as your preparation guide fabrication device, and as your provisional former. When the preparation is appropriately reduced for the material selected, the temporary can mimic the restoration. 

** The wax-up might be created with wax then duplicated with impression material and stone to create a cast, or it might be scanned to be duplicated with resin and printed or milled to create a model. 

3. 3. Use that provisional to highlight the talents of your team members.

You might LOVE to make those provisionals, but if your assistant is equally excited when it comes to recreating nature for the patient to appreciate, then it could be an opportunity for patients to see that your assistant does much more than set-up, clean up, and hand you an instrument. My dental partner, Cheryl, (who is also my wife) and I actively sought out things that could help our patients experience our team as much more than our helpers. 

As we all know, dental assistants are an integral and vital part of what the practice is and are a powerful force in how and why patients ask for dentistry. Assistants who fabricate provisionals have an opportunity to be seen differently, and we were always looking for ways to create partnership with them in our treatment. 

4. 4. Take pictures of them.

Photographs of the temporary will make it easier for the lab to design the outcome. They will be able to see what you are thinking, able to visualize what you want, AND maybe even more importantly, see what you do not want. With anterior provisionals, I have frequently noted to my ceramist, “Please put the incisal edge in exactly this position vertically and horizontally in the face, then use your artistry to create the tooth that belongs in the face you see in the photographs of the patient before, prepared, and temporized.” 

There were many times when the technician was able to see and create effects that I might have not recognized as being “just the thing that would make these teeth extraordinary.” And don’t forget to show the patient the photograph. 

5. 5. Love the material you make the temporary with.

The better the provisional material is at holding tooth position and functional contact, the less adjustment we’re going to have, so using a high-quality material is important. There are a lot of them out there. I like bis-acryl materials that polymerize with a hard surface, have little or no oxygen inhibited layer, and can be polished easily. The polish is more about feeling smooth than about the shine. Ask you patients how their provisional tooth “feels” when you are done, so they sing your praises. 

6. 6. Use high-quality core material.

When you use a good core material the prep will be smoother, making it easier to fabricate nice provisionals. Ideal prep form goes a long way toward better provisionals. 

7. ASK your patient to tell people.

As noted above, when you can elicit an emotional response about the awesomeness of your provisional, ask the patient to tell other people, “….and this is just the TEMPORARY!” 

Trying to match the color of the cement between the abutment and the dental implant crown in the anterior can be very frustrating. Here’s a trick that works well for me. 

A while back I was struggling to match the color of the cement between the abutment and an anterior implant crown. I always try-in the abutment and the crown and try to confirm the shade before they are put together. We do this because the laboratory can’t redo the shade once they’ve bonded the crown and the abutment for screw retention without trying to separate the cement, which is difficult. 

Over the years, it was a challenge to replicate the opacity of the cement used to connect the titanium abutment and ceramic crown. I’ve tried using some of the opaquest try-in paste on the market. 

In the case I referred to above, we thought we had it. My lab cemented it together and I put it in. I could see the opacity of the cement through the restoration. So, we had to take it apart and try again. My laboratory technician shared with me a trick that he had learned from one of his other dentist clients. And that was to simply go to CVS, Costco, or Target and buy good old fashioned liquid white out.  

Now, I put a very tiny amount of whiteout on a micro brush and paint it on the inside of the labial surface of the crown on the intaglio surface. Then, I use a bit of translucent try-in paste to seat the crown. 

The whiteout works well because it is basically titanium dioxide and water with preservatives—the same white compound that is in super white sunscreens. In my opinion, it is relatively safe to use, and I can see what the implant will look like when the pieces are cemented together. 

How Ivoclean Works 

Lee Ann Brady, DMD 

Saliva on the inside of restoration surfaces greatly reduces the bond strength between the porcelain and the cement but during the intraoral try-in process, it is inevitable that there will be saliva contamination. 

Most dentists I know use Ivoclean from Ivoclar to clean their indirect restorations after try-in. It is an incredible material for removing saliva and other contaminants that the restoration is exposed to during the intraoral try-in process.  

We trust Ivoclean to fully remove resin or traditional cements, as well as saliva and red blood cells to produce a super pristine surface.  

Did you ever wonder how Ivoclean works to get rid of saliva and all the other debris that gets on the inside of a ceramic restoration or metal base?  

Intraoral contaminants contain lots of phosphates. Ivoclean contains suspended zirconia particles that have an affinity for phosphates. The zirconia particles pull towards them the phosphate-laden particles, so when you rinse off the Ivoclean, the intraoral debris is rinsed away leaving a clean surface. 

Note: We don’t want to expose zirconia restorations to something that contains phosphates or includes phosphoric on the label because there is a strong attraction at an elemental level between zirconia and phosphate particles. To neutralize the ionic bond between saliva phosphates and zirconia, we need an alkaline solution such as potassium hydroxide (KOH). This is the active ingredient in products such as ZirClean from BISCO. 

Why Use an Essix Retainer Versus a Flipper During Dental Implant Therapy 

Lee Ann Brady, DMD 

When it comes to choosing a provisional during implant therapy in the anterior aesthetic zone, we have two removable options. One is called a “flipper.” It’s an interim partial denture composed of an acrylic base and a denture tooth. The other is an Essix retainer.  

There is no question that both options are taxing for the patient for the three to five months that the patient is edentulous and must deal with having this removable device to replace the tooth. So, I always tell my patients that they are going to have to manage the provisional for that time, but it’s worth it because, in the end, they have replaced the tooth with an implant with all the benefits of an implant versus an alternative prosthetic solution. 

In my practice, I use Essix retainers in nearly 100% of the cases. Why? Because an Essix retainer is tooth-borne. The pressure is placed on the teeth and not on the surgical site. In the case of a flipper, the prosthesis is primarily tissue-borne with a little pressure placed on the adjacent teeth. We really don’t want any pressure on the surgical site while it is healing. Pressure can induce biological problems in bone grafts and connective tissue, which affect the long-term outcome. From an aesthetic perspective, the most challenging thing about anterior implant aesthetics is replicating the size, shape, and position of the tissues of the alveolar ridge and papilla. I want to do everything I can to eliminate pressure on the healing tissue. 

In my practice, we do Essix retainers that don’t have a full solid tooth in them. Instead, we simply paint flowable on the facial so that there’s zero pressure anywhere around that surgical site after extraction, after grafting, and after implant placement.  

In addition to explaining the improved outcomes associated with using an Essix retainer, I assure my patients that the retainer will be more comfortable to wear than a denture and be easily removed by them for eating, for drinking liquids other than water that are likely to stain the retainer, for teeth cleaning, and for cleaning the prosthesis. When out in public, such as in a restaurant, patients may carefully eat while wearing the Essix retainer.  

We use the words “multilayer” and “multilayered” to describe lots of different materials from different manufacturers. If your lab tells you they use multilayered zirconia on a restoration or abutment, do you know what you are getting?

One of the ways we use the word multilayered is to describe a puck of zirconia that has two different types of zirconia.

Some of the pucks are a layer of 3y (the strongest but least aesthetic zirconia) with a layer of 5y (the weakest but most aesthetic zirconia). The laboratory technician puts the restoration design in the puck so that the 5y is on the facial of the restoration where you can see it and the 3y is on the incisal edge and lingual.

There are also pucks that are 4y zirconia layered with 5y zirconia. The 4y zirconia is a middle grade of both strength and aesthetics. In this case, the 5y is on the facial and the 4y is on the incisal edge and lingual.

Thus, there are two different ways to mix strength and aesthetics in one puck of zirconia and both variations are called “multi-layered.”

Complicating this even more, we use “multi-layered” to describe layers of chroma gradient or translucency. The laboratory technician can put the design pattern in the puck to achieve different gradient effects, but the restoration is all of one strength (one type of zirconia).

One of the challenges today with zirconia is that there is no place on a laboratory prescription to specify one of these varieties, and it needs to be clarified when communicating with your lab technician. Ask what your lab technician means by “multilayered zirconia,” and communicate clearly the multilayering you want used.

The search for temporary cements has been a long one over the last decade as my practice has moved away from porcelain fused to metal full coverage as the “go to” indirect restoration. The difference in mechanical retention, aesthetics and final placement protocols places different demands on our temporary cements. There are quite a number of criteria we want out of a temporary cement, and finding it all in one product was the challenge.

• Great Retention
• Easy to Remove
• Easy to Clean the Prep
• Eugenol Free
• Easy to Clean Excess During Cementation
• Esthetic/Translucent
• No Sensitivity
• Doesn’t grow black Scuz

Having played with many of the temporary cements on the market there are many that meet most of the criteria, but I hadn’t gotten everything I wanted until I started to use TempoCem ID from DMG America.

Why I am so pleased with TempoCem ID:

• It is a resin-based temporary cement that actually changes from slightly opaque to translucent when you move through the curing process.
• The initial opacity that remains — even at the gel phase, makes cleaning away the excess very easy.
• Once all the excess has been cleaned off, a final cure takes you to fantastic retention and a beautifully esthetic cement.
• The chemistry allows you to place the final restoration without worry of incompatibility with adhesive or traditional cement systems.

Whether for full or partial coverage TempoCem ID has become the temporary cement of preference in my office.

One of my goals with composite restorations is to do as much of the forming and shaping prior to picking up a curing light as I can.

The material is easy to sculpt before it is cured, and access to the surface of the tooth is easier with hand instruments. Once I have placed all the composite and have a dense fill, I remove as much of the excess sitting above the final occlusal surface as I can. With this step accomplished, I turn my attention to creating the occlusal anatomy.

My OptraSculpt handle and disposable tips from Ivoclar Vivadent are perfect for this. The various tip shapes allow me to create incline planes, occlusal grooves and the curve of the marginal ridges into the occlusal embrasures. This process often removes and shapes the composite. My assistant holds a two by two that has been moistened with rubbing alcohol to remove the excess off the end of the instrument. I can place a different shape on each end of the instrument, or I can interchange them as I need them.

Using a series of disposable tips enables me to work without the composite sticking. This has reduced the necessity for meticulous management of expensive instruments which frequently need replacement. And, I resist the desire to use dentin adhesive or an unfilled resin on the instrument to reduce sticking.

Most dentists think of zirconia as the highest strength, all-ceramic material that they can use to balance esthetics and durability.

It is the material we go to for patients with occlusal risk, for second molars at higher risk of fracture and for all-ceramic bridges.

You have likely heard of flexural strengths of 900-1,400 mPa being thrown around. While this is the flexural strength of a certain category of zirconia, you might not be aware there are different types.

Not all Zirconia has the same strength.

Because dentists have demanded manufacturers make versions that are more esthetic, some types are not as strong and durable as others. The general rule of thumb follows. The prettiest zirconia is the weakest. Conversely, the opaquest zirconia is the strongest. For example, the white opaque zirconia that visible as the substructure on the underside of a bridge is the highest strength and may have flexural strengths of 1,000-1,400 mPa. The other end of the spectrum is the highly esthetic materials we refer to as “translucent,” “crystal” or “esthetic” zirconia, and they may have flexural strength of 500-700 mPa. There is also a category of material with strengths in between.

Because there are many manufacturers and brands, you will want to be familiar with what your lab offers. Ask your lab what types of zirconia they can provide, and their specific strengths. Ask your lab how you should specify which zirconia to use for a given case. This, of course, will be determined by the esthetic and functional demands of the individual situation.

Some labs can note your preferences in their computer. For example, they can note that you always want the middle strength material for second molars, the highest strength for bridges and the prettiest material for premolars.