Primescan Biocopy - A Valuable Resource

Thomas Monahan Anthony Ramirez
3 years ago

e.max has been the main restorative material in my practice for in office CEREC® restorations for a decade. This report documents a mandibular anterior veneer case that illustrates the superior quality of fit, esthetics and ease of use with this material. Even though I am constantly solicited with new materials, I find myself maintaining at least a 75 % use of e.max for crowns, onlays, veneers, 2–3-unit fixed bridges and implant restorations. My first experience with CEREC was creating a single unit crown during a CEREC ACCEPT program. Having no technical nor clinical experience with the digital production of in office restorations I fabricated a crown that I glazed in Scottsdale and cemented onto my patients’ first premolar the very next Monday at my Brooklyn N. Y. office. This crown was designed and milled after scanning a stone die that my local lab had poured and used to fabricate a PFM crown. The esthetics, marginal fit and the ability to have control of the process sold me immediately and was the impetus for my transition into a fully integrated digital practice. I was able to compare this crown against the lab fabricated PFM and found that there were many advantages to being able to produce in office restorations. I was able to control the morphology, occlusion and esthetics with increased proficiency, all while speeding up production and improving the quality of my restorations.  No longer dependent upon a lab to create all my restorations saved me the turnaround time, reduced lab fees and the cost of impression materials immeasurably.

What began as mostly single unit restorations has expanded into producing Implant crowns, bridges and multiple unit cases. Having control of occlusion, contour and esthetics elevated my ability to produce high quality restorations in a timely manner that satisfies or exceeds patient expectations in an extremely high percentage of my cases. Over the years these restorations have performed exceptionally well in function with a nearly 100% success rate.

A Valuable Design Option-BIOCOPY

Having restorations replaced multiple times due to porcelain fracture, recurrent decay and endodontic failures led this patient on a multi-year treatment plan. Porcelain fractures occurred because of inadequate occlusal clearance and clenching. I diagnosed and presented him with a full mouth rehabilitation years ago, but he declined because he had his dentition restored more than once prior to becoming our patient. Many of his existing restorations have since failed and were replaced with crowns. Multiple teeth became hopeless and required implant tooth replacements.  For more than a year lower anterior veneers would de-bond and be re-bonded during emergency visits. Porcelain incisal wear throughout the mandibular anterior segment, marginal ledging and recession of the gingival tissues exposed tooth structure, creating triangular spaces that became food traps. While travelling out of the state on a business trip the # 25 veneer popped off again. This incident convinced him to have teeth # 22-26 treated along with # 28. It took this embarrassing occurrence for him to finally agree to their replacement. (fig. 1)

Figure 1: Pre-operative condtion of lower veneers #s 22-26 and crown # 29.

The case was challenging due to his occlusion and the narrow mesial distal incisor widths. I planned to utilize the Biocopy Design Mode feature in Chairside software as the blueprint and basis for the final design albeit with modifications to enhance the outcome. I captured a digital impression with Primescan of the existing dentition in a Biocopy folder. I selected e.max as the material to manufacture his veneers because these restorations in my experience are esthetic, strong in function and produce a superior marginal fit that seal the underlying tooth structure and prevent recurrent decay. (fig. 2-3)

​Figure 2: Digital impression of existing mandibular dentition (Biocopy) for use in design of new restoration morphology and occlusion.​

​Figure 3: Intraoral photo of prepared teeth 22-26.

I sectioned the existing porcelain veneers and modified the preparations. The first modification made was to provide 1.5mm of incisal reduction and the second was to extend the mesial and distal preparations inter-proximally towards the lingual of each tooth. Tooth # 22 was already prepared for a crown, so this preparation was extended apically to gain additional coverage of the cervical margins. Retraction paste was injected into each sulcus and left on the teeth for about 90 seconds rinsed off to adequately expose each margin. Primescan captured these margins quickly with incredible detail. The opposing arch and bite were optically impressed completing all the necessary information needed to design and manufacture the case. Temporization was quickly accomplished with a putty matrix and Luxatemp bisacrylic in a B1 shade, bonded onto the preps in one piece. I use ExciTE F which is a light-curing, fluoride releasing, single-component total-etch adhesive. One difference is I do not etch the teeth and rely on the primer to retain these provisionals along with wrapping the material inter-proximally to provide mechanical retention. I rarely have provisionals detach between the impression and the insertion visit when using this technique. This shade was lighter than adjacent teeth but would only remain in place for about 1-2 weeks.

The scans moved from the Acquisition Phase to the Model Phase where each preparation was marginated. The Biocopy model was then used to outline any usable information in the preoperative morphology that could be helpful in the initial design phase of the newly proposed restorations. I made use of the grid feature to create an even incisal plane and improve the occlusion. I sent my scans to a digital lab to print dies and mount upper and lower models for me to make any necessary final adjustments of the milled restorations prior to their crystallization and insertion. (figs. 4-7)

​Figure 4: ​Model phase of digital impression being marginated.

​Figure 5: Margination Completed 22-26, 28.

Figure 6: Margination completed and checking clearance after design.

​Figure 7: Occlusal Clearance.

This case is a good example of how using the Biocopy feature can make the fabrication and insertion of CADCAM restorations effortless, requiring little to no adjustments during the insertion phase. Providing enough interocclusal space was an important factor in developing fracture resistant restorations. The provisionals remained in place without any issue and once removed I was able to bond in the five anterior restorations using Ivoclar’s Variolink esthetic light plus resin material. The restorations were etched with 9.5% hydrofluoric acid for 15 seconds then silanated. The teeth were treated with a total etch technique prior to luting each e.max restoration. This is a permanent light curing or dual curing luting composite that is easy to use and maintains shade stability over time. The shade selected for these restorations was MT B1. This displays a higher value, with a medium transluscency, which blended in well with the existing dentition. This case documents how these monolithic ceramic blocks can be processed in office with efficiency and high quality to satisfy even demanding restorative situations. (figs. 8-15)

​Figure 8: Copy line # 26​.

​Figure 9: Using Biocopy as a Reference for Designing Restorations.

​Figure 10: Designing restorations using grid (controlG), ready for mill.

​Figure 11: e.max blue phase restorations milled and fitted on printed model.

​Figure 12: Final Design of Restorations Ready to Mill.

​Figure 13: Milled e.max on model, checking occlusion prior to crystallization phase.

​Figure 14: Glazed and finished e.max restorations ready for insertion.

A 9-month recare visit documented no change in the appearance of these veneers and a favorable the tissue response to the new ceramic material as compared to the original presentation. I have total confidence that these restorations will remain esthetic and function for years to come. (figs. 16-18)

​Figure 16: Veneers #s 22-26 Bonded with variolink esthetic high value before separation.​

Figure 17: Occlusion immediately after cementation of 22-26 and 28 e.max restorations.

​Figure 18: 9 month recare visit 22-26, 28 e.max restorations.

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