Using a CAD/CAM workflow gave the patient the opportunity to visualize the final restorative outcome.
The goal of cosmetic and restorative dentistry is to improve the health and integrity of the patient’s dentition as well as the patient’s self-image and confidence. I like to think of dentistry as a performance of sorts. In addition to my role as a cosmetic dentist, I also wear the hats of an artist and communicator, paying attention to every detail, beginning with the initial patient consultation through treatment planning, treatment, and follow-up care.
For this case, a wax up was created so the patient could see how the new teeth would look in his mouth. Giving the patient an opportunity to visualize the final restorative outcome helps with treatment acceptance and allows for discussion of any adjustments or fine-tuning prior to producing the restorations.
A 61-year-old healthy man presented with 20-year-old porcelain-fused-to-metal (PFM) crowns on both upper centrals with margin exposure (Figure 1). The shade of the PFMs was brighter than his surrounding natural dentition, and the patient also suffered from incisal and occlusal wear on the lateral incisors, canines, and bicuspids. Due to the incisal and occlusal wear, full-coverage crowns were recommended on teeth #4 through #13.
The patient was unhappy with the appearance of his teeth and reluctant to smile, so the treatment objective was foremost to protect the integrity of the patient’s dentition while also enhancing his confidence by changing the form, shape, and color of his teeth to result in a more esthetically pleasing smile.
Preoperative case photos and a full-mouth digital impression are taken with CEREC Primescan (Dentsply Sirona) (Figure 2). This information is important for better communication and understanding of the treatment plan and goals with the patient.
A 3D model of the digital impression is printed using a SprintRay Pro 55S (SprintRay Inc). The physical model is then used to create a wax up modifying the size, form, and shape of teeth as needed to visualize the treatment outcome and to produce a silicone key.
The silicone key (Figure 3a) is used to transfer the mock-up into the patient’s mouth (Figure 3b)—a very important step—because the patient will make his final decision to proceed with treatment at this appointment. Once the case is accepted and all financials are taken care of, we are ready to schedule “The Big Day,” which I refer to as “Same-Day Personalized Smile Transformation.”
On the big day, we start with tooth preparation using the biologically oriented preparation technique, referred to as BOPT, which is a vertical preparation or feather-edge technique. The goal of BOPT is to achieve high-quality and esthetic results in terms of soft-tissue stability and prosthetic/tissue interface. Next, a digital impression of the preparations is taken with CEREC Primescan (Figure 4), and the restorations are designed on screen using CEREC SW 5.2 (Figure 5).
After designing the restorations for teeth #4 through #13, the crowns are milled using both a CEREC MC XL and CEREC Primemill (Figure 6). Because this case requires 10 restorations, using 2 milling machines in tandem greatly reduces the amount of time needed to complete the treatment. The crowns are milled from blocks of VITA Suprinity® PC, a high-strength, partially crystalized zirconia-reinforced lithium silicate material with excellent esthetic attributes. Once milled, the sprues are removed, and each restoration is shaped and texturized with Meisinger’s Twist Polishers (green and blue) (Figure 7) on a low-speed analog electric handpiece to eliminate any scratches on the ceramic before the staining and glazing process. Following texturization, CERABIEN™ ZR stain and glaze (Kuraray Noritake Dental Inc) are applied to each restoration to impart a natural appearance with lifelike vitality.
A preoperative photo. Notice the metal exposure on the porcelain-fused-to-metal crowns (teeth #8 and #9).
PANAVIA V5 Cement is dispensed into the intaglio of each crown and seated individually. Excess cement is readily removed with a brush.
A 3D model of the preparations is produced by exporting an .stl file from the CEREC software to the SprintRay Pro 55S printer, allowing us to passively test the fit of each restoration on the model (Figure 8). This step ensures that the final restorations will fit perfectly before delivery.
“The Crowning Achievement”: We deliver the final restorations. Using a modified technique in isolation, a rubber dam is used for final cementation with PANAVIA™ V5 cement (Kuraray Noritake Dental Inc). First, PANAVIA V5 Tooth Primer is brushed onto all surfaces of each preparation (Figure 9). Next, each crown is prepared for final cementation by first applying CLEARFIL™ CERAMIC PRIMER PLUS (Kuraray Noritake Dental Inc) into the intaglio and allowing it to dry, followed by dispensing PANAVIA V5 cement into the intaglio and seating the restoration with uniform pressure, letting the paste flow evenly around the preparation (Figure 10). Excess cement is removed with a brush, followed by a tack-and-wave cure technique. Finally, floss is used to make sure we have solid interproximal contacts.
Upon seeing his new teeth in the mirror, the patient could not keep himself from smiling and admiring his new look (Figures 11 and 12).
Whether the procedure calls for a single crown or a full-smile restoration, CAD/CAM dentistry gives clinicians the power to provide fast, safe, and efficient same-day dentistry, delivering beautiful, individualized smiles that patients are proud to show off.
The last, but not least, piece of the puzzle is bonding. This step is crucial to achieving long-lasting restorative integrity. I prefer the Kuraray Noritake family of adhesives, cements, tooth primers, and ceramic primers because they have demonstrated exemplary outcomes in clinical practice over the years. The company is a pioneer in methacryloyloxydecyl dihydrogen phosphate, or MDP, adhesive technology, and in my experience, PANAVIA™ V5 cement provides great color stability and long-term bonding confidence.