By: Dr. Brent Harris

Ceramic veneers have for years been a long term, highly esthetic, conservative treatment option for improving cosmetics in the anterior dentition. When fabricating single or multiple veneers that are individually spaced with natural teeth to the mesial and distal, the provisional veneers cannot achieve stability through their connection to each other. Therefore, one challenge that faces many practitioners is creating provisional restorations for these individual veneers that will predictably maintain their position throughout the transitional period while the final restorations are being created. Using Planmeca’s Planscan system in conjunction with Ivoclar Empress Multi-block CAD/CAM ceramics, this problem can be avoided and highly esthetic ceramic veneer restorations can be fabricated in one visit, eliminating the need for provisionalization.

 

1-preop4 Image 1

 

A 26 year old female patient presented for a consultation and complained that her lateral incisors were, “Darker and less prominent than her other teeth”. She was also unhappy with an excessive show of gingiva apical to her right lateral incisor. During this initial visit, digital preoperative photos were taken, alginate was used to impress the patients teeth and poured up in dental stone, and a base shade based on teeth 6,8,9, and 11 was recorded. While the maxillary central incisors and canines were closest to shade A1, the central incisors had some areas that were brighter and fell into the shade range of Ivoclar’s Empress BL3 ceramic. BL3 was chosen as the ceramic block shade since it is relatively easy to add warmth and color to the ceramic, but more difficult to increase the brightness through characterization. The patient was then appointed to return for a same-visit veneer procedure for teeth 7 and 10. Between appointments a basic wax up was done on the stone model to create a fuller facial form and more pleasing gingival height for teeth 7 and 10. The Planscan was then used to scan this wax-up as a preoperative digital ‘clone’ model (Image 2). Based on the thickness of wax used to create the ideal facial contours, it was determined that minimal enamel would need to be removed during the preparation process. Since a model of the lower teeth had been fabricated to guide in building proper incisal position for the maxillary wax-up, this model was scanned in to the patient’s digital file and saved as the opposing dentition.

Image 2
Image 2 

The patient returned for the single-visit veneer procedure. Local anesthetic was delivered by infiltration to numb the gingiva apical to #7 and #10 prior to gingivoplasty. A diode laser was used to conservatively re-contour the gingival margins to create symmetry in height and architecture. Had the gingivoplasty not been necessary, the following single visit veneer procedure could have been performed without any anesthetic. Using a highspeed diamond, a minimally invasive 0.5 mm chamfer margin was placed along the gingival margin. As this finish line blended interproximally, the depth was increased to just under 1mm. By increasing the depth and going slightly interproximally, the risk of visualizing the junction of lighter ceramic and darker tooth structure was minimized. The anterior maxillary dentition was then scanned intraorally (Image 3), along with a “bucal bite” scan (patient in maximum intercuspation).

Image 3
Image 3 

A virtual stone model of the intraoral scan was fabricated and the margins marked on the computer (image 4). Using Planmeca’s intuitive Romexis software, the preoperative scan of the wax-up and the intraoral prep scan were superimposed (Image 5) and used to generate a restorative design based on the preoperative digitally‘cloned’ wax-up. This restorative design can be easily manipulated in the software and altered in a myriad of ways. It is often ideal to very slightly overbulk the restoration facially (Image6) in order to plan for post-milling chair-side adjustments to develop the most accurate facial texture, line angles, and symmetrical reflection of light with the adjacent teeth. 

Image 4
Image 4 
Image 5
Image 5 
Image 6
Image 6 

While very subtle textures and contours can be visualized on the computer screen, even the most detailed milling systems are still limited by their cutting instruments tip size. While large scale primary anatomical details such as mamelons, concavities, and minor incisal edge discrepancies can be accurately milled, secondary and tertiary anatomical characterizations such as subtle horizontal growth lines, vertical striations, and surface imperfections to reflect light are better facilitated by hand. Once the digital design was completed, the restorations position in the Empress Multi-Block was chosen (Image 7). By dropping or raising the restoration in the graded-translucency block of ceramic, the level of incisal translucency or opacity can be altered.

Image 7
Image 7 

One of the advantages of using Empress Multi Block ceramic is that upon milling and prior to crystallization, the block carries its full color characteristics. This is in comparison to IPS Emax ceramic that maintains a violet coloration until crystallized. Following milling, the veneers were tried in to the patient’s mouth. The electric high speed hand piece speed was lowered to approximately 15000 rpms and a rounded shoulder diamond bur used to slightly contour the facial aspect of the restoration to match its adjacent dentition. These adjustments were made with the restoration in hand, then the veneer was placed back intraorally to check any changes. This post milling adjustment step is imperative to creating a life-light ceramic restoration that does not stand out as being too reflective or too flat when light hits it. It is seldom that these adjustments will take more than a couple minutes per tooth. A small smear of water or glycerin can be wiped over the facials of the veneers and their appearance next to the adjacent teeth compared under direct and indirect light. Once the final detailed shape and texture was achieved, the restorations were cleaned with water, dried, and stain and glaze applied chair-side. By staining the veneers next to the patient, it allows the dentist, assistant, or in-office technician to visualize additional translucencies, chalkiness, striations, and areas of increased warmth on the adjacent teeth. Adding these very fine details with stain, will create a camouflage effect and create a more life-like polychromatic final result. Too often clinicians and lab technicians alike, will create a restoration that is ideal in shape and correct in its base color, but have it still fall short cosmetically due to a lack of characterizations around the incisal edge, cervical, and line angles. In this patient’s case, white stain was used to create a slight incisal chalky halo, and a small amount of violet mixed with blue stain was laid in a few random spots just apical to the white halo to create a very subtle contrast. This same violet-blue mix was used very sparingly on the disto-incisal corners and running up the mesial and distal line angles of the laterals to create depth. An endodontic file serves as an outstanding instrument for delivering minute amounts of stain and muddling it into chalky or stained appearing areas or drawing it into striations and craze lines. Finally, a very light amount of “A” shade body color was added near the gingival region and blended into the cervical 1/3 of the restoration.

The stained and glazed restorations were attached to firing pins with Object Fix, and fired in the programat cs Crystalization oven on the Empress setting. After crystallization, the veneers were cleaned with water and tried in the mouth for final esthetics. At this stage digital photography is a great tool to ensure ideal match of color, texture, and light reflection. Many times after visualizing a tooth over a long span of time, subtle discrepancies will present themselves more readily in a photo. Often it is important to look at the restoration under fluorescent as well as natural light. If the restoration looks good under fluorescent light, flash photography, and in natural sunlight, then it’s a sure bet that the patient will be pleased once they leave the office. Variolink Veneer try-in pastes were utilized to visualize the most ideal cement color. In this case high value +1 shade was selected. The teeth and restorations were prepared following the variolink veneer cementation protocol and thin, white, plumbers tape was tightly wrapped around the mesial and distal surfaces of the adjacent teeth. The restorations were seated, tack-cured with an LED curing light, the contacts cleared with floss, and then the restorations final cured with the light. The plumbers tape was then removed and a thin, yellow stripe flame, diamond, high-speed, finishing bur was used with copious water to smooth the margins. Super fine interproximal strips were used to ensure smooth floss transition interproximally. The margins were then polished with a rubber point and diamond polishing paste. The patient’s occlusion was verified through maximum intercuspation as well as functional movements. Due to the precision of Planmeca’s Romexis PlanCAD software, no occlusal adjustments were necessary.

The resulting ceramic veneers filled out the under contoured laterals, brightened the smile, and created a more confident and mature smile for the patient (Image 8). The patient returned after a week for a follow up to ensure the gingiva had healed ideally following the gingivoplasty procedure. The patient was very pleased with the changes and her resulting new smile (Image 9).

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