John C. Walker, DDS

In the current market, communication between the 

 and dentist is more important than ever. Dentists keeping a watchful eye on their overhead are faced with a lab bill every month that’s reflective of the 

 and materials they’re selecting for their patients.

Close communication between the dentist and the lab about material science when selecting restorations is important, but it also can include discussion of different price points available from the lab for these products and materials.

A lab’s goal is to retain its clients, and a dentist who has to seek out and use multiple labs to obtain either higher quality work or lower priced restorations isn’t a viable path to this goal. Proper communication can lead to high quality restorations at an affordable price.

Much has been written about e.max Press from 

 and its ability to provide reliable strength and beautiful lifelike restorations. The lithium disilicate material can be waxed to full contour, pressed, stained and glazed, or be cut-back after pressing and porcelain layered on for increased translucency while providing a vast range of characterization and custom shade matching options.

The cut-back technique has become the standard when fabricating anterior restorations with e.max, but Ziemek Dental Lab has discovered that highly esthetic restorations can be produced with a simpler stain and glaze process. While still delivering esthetics, this technique allows dentists to place monolithic e.max restorations in the esthetic region at a lower cost.

With adequate prep reduction and custom abutment design, the Low Translucency (LT) ingots can mask dark stumps and even titanium custom abutments while still providing natural, lifelike translucency along with 400 MPa strength.

Matching a single anterior restoration to existing natural dentition is among the most challenging tasks a lab undertakes, and this is unchanged when going monolithic. What does change is the workflow in the lab, and this change can allow a lab to potentially offer these restorations as a lower priced alternative to layered ceramics in the challenging anterior region.

The strength of e.max Press, and the versatility provided by waxing and pressing it, allows a lab to design the restorations in virtually any style a PFM can be designed, such as guide planes, rests and undercuts in conjunction with Partial Dentures, which was done in the case presented here.

When using e.max Press monolithically, there is no incisal or effect porcelain layered on the buccal, and esthetics are achieved with only the e.max material and the e.max stain/glaze. Waxing, pressing and finishing anterior e.max Press monolithic restorations can be accomplished by lab technicians without porcelain layering experience, reducing the cost for the lab to produce them, and freeing up the more experienced technicians for cases requiring their specific skills and knowledge.

Fabricating e.max Press monolithic restorations for multiple unit anterior cases with straight-forward shades can allow labs of any size to offer lower priced anterior esthetic options on their menu.

Although the case featured in this article isn’t a basic anterior case, the shade matching was similarly simple because all the existing teeth were restored. The final cost incurred by the dentist on this case was drastically lower than if the restorations chosen were e.max Press layered with ceramics, or if the dentist had chosen PFMs with the price of gold what it is today.

A 74-year-old female patient presented in excellent health, but with multiple missing and decayed teeth, severe wear fractures and very dark discoloration, along with existing PFMs of varying shades, and a large diastema between tooth Nos. 8 and 9 

The dentist determined the need to open the patient’s bite to even out the plane of occlusion and provide room in the areas of super eruption for a mandibular removable prosthetic device (RPD). On the maxillary arch, the decision was made to restore the teeth and replace the existing crowns on tooth Nos. 3-13.

The restorations chosen were e.max Press monolithic, which accomplished a few important goals for the restorative team and the patient. It allowed the lab to mask the dark stumps adequately while still providing natural looking translucency, it allowed the lab to design the mandibular restorations in conjunction with the new RPD, and it allowed the lab to complete the entire case for about  25% less than if the same case was completed with layered e.max restorations, and about 40% less than PFMs. That’s a substantial savings on a case of this size, without sacrificing strength, esthetics or design options.

Pre-op impressions taken by the dentist were used to fabricate models and diagnostic wax-ups that followed the dentist’s prescription to open the bite approximately 3 mm. After the dentist and patient approved the wax-ups, they were used to fabricate temporaries, the teeth were prepped, stump shades recorded and the temporaries placed 

After seeing the stump shades, the technician and dentist decided LT (low translucency) ingots would be the best choice to mask the dark stumps while still creating a natural translucency. At the lab, an impression was made of the diagnostic wax-up and a wax injector was used to quickly duplicate the crowns on the working model 

. This technique not only saves the lab the time and labor of waxing, but also provides very accurately pressed crowns that require minimal time to finish.

The wax-ups were invested and pressed with e.max LT A1 ingots, de-vested, and finished on the model. e.max stains were applied at the gingival to enhance the chroma, on the line angles and to create a mammalon effect, as a basic translucent overlay, and the Empress Universal White for some highlights.

Next the maxillary crowns were seated, the dentist prepped the mandibular teeth 

, recorded the stump shades and sent the impression to the lab, again fabricating the temporary crowns from the original diagnostic wax-up. The lab repeated the wax injection procedure to create the mandibular wax-ups, this time using a light colored wax as the dentist requested a wax try-in to check the patient’s occlusion, and to aid the design of the mandibular RPD.

The temporaries were removed and the wax-ups tried in 

, and minor corrections for occlusion or esthetics were performed. The wax-ups were then sent back to the lab, invested and pressed (again, LT A1 ingots were used), and the same stain recipe used for the maxillary crowns was applied to the pressed mandibular restorations 

. The crowns were seated, and impressions were taken for fabrication of the RPD.

The RPD was fabricated and tried in for fit, with only very minor adjustments required. The authors and the patient agree the final result is a great success and a big improvement esthetically and in her overall quality of life 

This case presentation illustrates how a dental lab can be proactive in research and development as well as communication with its dentist clients, informing them about products and materials that are priced lower, while still providing the dentist and patient strong and esthetically pleasing restorations with flexible design possibilities. 

The authors would like to acknowledge and thank Sheryl Wolden, CDT, for her excellent work on the e.max Press restorations completed for this case.

; John C. Walker, DDS, can be reached at: 

Articles

In the current market, communication between the dental lab and dentist is more important than ever. Dentists keeping a watchful eye on their overhead are faced with a lab bill every month that’s reflective of the new dental products and materials they’re selecting for their patients.