How collaborating with your lab can maximize the potential of the single-tooth restoration.

In a tough economy, it’s more important than ever that dentists work to meet and exceed each patient’s expectations. By performing to the best of one’s abilities at every appointment, a dentist can develop stronger relationships with existing patients, as well as gain new patients.

The single-tooth restoration provides a good example of the potential an everyday procedure can have for the office. If this treatment impresses the patient, the dentist likely will keep that patient for a long time. But to do the best work on a single-tooth restoration, a dentist needs both excellent clinical skills and an excellent relationship with the laboratory.

A side-by-side relationship
The authors work in a unique environment for laboratories and dentists, in that our offices are next door to one another. This provides a number of advantages for both the dental office and the laboratory. In many cases, the lab technician is invited into the dental office to consult on a case from the early stages.

For the technician, the opportunity to see the patient in person allows for a much more complete understanding of the patient’s wishes and expectations, as well as his or her complexion, age, existing tooth shades and other variables that cannot be conveyed as fully via photograph. For the dental office, this arrangement speaks volumes to patients about the level of care going into their restorations.

The technician also is given an opportunity to consult on appropriate materials and advise on preparations. In complicated cases, the ability to collaborate on a treatment plan helps both the dentist and the technician ensure there are no miscommunications. Even in relatively simple cases such as a single tooth, working side by side helps ensure optimal results and shows patients that each restoration is important to the dental team.

Managing patient expectations
An additional advantage to the lab technician’s presence in the operatory is his ability to consult directly with patients and assist the dentist in managing patient expectations about what’s possible to achieve in any given case.

Many of today’s dental patients have a much higher level of dental knowledge than in the past, thanks to factors like direct-to-consumer advertising by dental companies and patients’ own Internet research. As a result, many dentists have experience treating patients who ask for things like a “Julia Roberts smile,” or who want to be treated with a particular restorative material.

While the dentist can do his best to explain what’s realistically possible, having the technician on hand to offer the lab perspective adds weight to the dentist’s recommendation. The lab technician can advise patients on factors such as the limitations of a restorative material, or finding the right balance of function and esthetics.

Attention to detail
In any restorative case, attention to detail can mean the difference between an esthetic, well made restoration and one that looks unnatural and requires significant adjustments.

With the lab technician on hand to observe the preparation steps, the “two heads are better than one” adage applies very well. The technician guides the preparation process and gives input based on the dentist’s selected material. Sharp angles and underprepared areas can be corrected before they become an issue in the later stages of the case.

For the dentist’s part, the impression step is very important for single-tooth restorations. Dentists always should be vigilant about their material selection and careful adherence to recommended impression taking procedures.

Most dentists use several impression materials in practice, all of which have their individual nuances. Some dentists can feel like Goldilocks when searching for a material that has the combination of properties that is “just right.”

In many clinical situations, 3M

ESPE’s Imprint™3 VPS Impression Material has the combination of stiffness, flowability and the ability to capture fine detail that is just right.

Dentists who have practiced for some time may associate VPS materials with a lack of flowability, recalling when it was necessary to thoroughly desiccate an area before using the material to capture an impression. However, the technology used in these materials has evolved enough to allow greater hydrophilicity and improved flow properties.

Imprint 3 impression material, in particular, has been shown to be more hydrophilic than other VPS materials, which helps reduce the possibility of voids in wet conditions. But remember, even the most sophisticated material cannot counteract some of the common clinical errors that are made during impression taking (See Common impressing taking errors, p.64).

The following case demonstrates a single crown replacement, highlighting the proper impression taking procedure, as well as close communication with the laboratory.

Case report
The patient, a 39-year-old female, presented to the office with a primary complaint that she was unhappy with the appearance of an existing PFM crown on No. 7.

A cast post and core had been placed in the area nine years prior, and the crown appeared clunky and discolored next to the patient’s natural dentition, with unnatural contours and line angles (Fig. 1). The patient was especially self conscious of the appearance of the crown in light of her career as a dental sales representative. She was seeking a replacement or refinement of the crown to give it a more natural appearance so she could feel confident speaking with dental professionals on a daily basis.

During the initial visits, Orfan Dental Lab played an important role in answering her questions about the

materials and procedures recommended. After conferring with the patient, the dentist and technician recommended replacing the PFM with a 3M ESPE Lava™ Zirconia crown, which would appear more translucent but still opaque enough to mask the metal post. Although the patient was a sales rep for a competing manufacturer, she agreed with the assessment and consented to proceed with placement of a Lava crown.

At the next appointment, a matrix was made and a shade taken with the existing crown in place. A carbide bur was used to cut channels into the facial and lingual aspects of the crown, and it was cracked and removed from the cast post and core (Fig. 2). All margins were then redefined using magnification, with a two-plane reduction performed from the gingival to lingual aspect (Fig. 3). A shade was taken after the existing crown was removed.

A size 0 Ultradent (ultradent.com) cord soaked in a hemostatic agent was carefully placed around the tissue and left in place for 5 minutes. The retraction cord was removed and the area was thoroughly rinsed. Imprint™ 3 VPS Impression Material from 3M ESPE in a light body was syringed around the tooth, with care taken to push the material ahead of the syringe rather than dragging it behind. A tray prepared with adhesive was then loaded with heavy body material and placed into the mouth parallel to the long axis of the prep. Passive pressure was applied for 4 minutes and the tray was carefully removed (Fig. 4).  

A provisional was fabricated using 3M ESPE Protemp™ Plus Temporization Material (Fig. 5).

After placing the provisional the patient was excused and the case delivered to the lab next door. The crown was milled and the patient returned to the office two days later for a try-in. The provisional was removed and the crown was tried in at bisque bake to confirm the proper contour, length and phonetics (Fig. 6).

After determining no adjustments were necessary, the final firing, staining and

glazing were performed and the crown was cemented on the same day with 3M™ ESPE™ RelyX™ Unicem Self-Adhesive Resin Cement (Fig. 7).

The patient was pleased with the final appearance of the crown, which displayed much more natural contours and shading.

Discussion
This case exemplifies the kind of positive outcome that can be achieved with a single-tooth restoration, thanks to close collaboration and proper technique. The patient in this case was well educated about dental materials, and therefore had sophisticated questions for both the lab and the dentist about the procedure and their recommendations. The patient’s high expectations were met, and she was pleased with the level of attention she received from the dental team.

Most dentists, of course, do not have the luxury of working next door to a lab technician who can physically be in the room to consult with patients and advise them on treatments. But this does not mean they have no convenient way to communicate with the lab and make the technician an active part of the case.p.65).

Too often, dentists send a case to the lab with instructions along the lines of “PFM crown for tooth No. 7,” or “shade is B2 with a little bit of gray.” In these instances, unless the lab and dentist have worked together for a very long time, far too much is left open to interpretation, and the dentist is setting up the case for a poor outcome.

In any restorative case, the dental team’s ultimate goal is to deliver a quality product that makes the patient happy. By communicating more closely with their laboratory, dentists can deliver restorations that better meet patients’ expectations, as well as manage those expectations when they may be unrealistic.

For the dentist, an additional benefit of developing a close relationship with the lab technician is the ability to call on his expertise, whether in person or on the phone, when treating patients. The level of care and attention to detail this collaboration displays tells patients every effort is being made to help them attain the smile they most desire.