During the last 2 decades, dentistry has experienced heightened patient demand for more aesthetic restorations when dental treatment is required. Fueled by easily accessible and widespread information about the capabilities of modern dental procedures, such demands challenge the dentist and dental laboratory team to identify and incorporate new restorative materials and to use innovative fabrication/processing techniques to enhance long-term function and aesthetics for their patients. By incorporating digital treatment planning and proven clinical techniques and materials into our practices, the restorative team can ensure success when restoring a smile to proper form, function, and health.1
This article will discuss the importance of a systematic approach to treatment planning, tooth preparation, and proper material selection for a patient’s full-mouth case.2
Diagnosis and Treatment Planning
A woman in her mid 50s was referred by her general dentist for aesthetic restorative treatment. She presented with recurrent decay, worn direct composite resin and full-coverage crown restorations in the maxillary arch, and abfractions with cervical decay (Figures 1 to 3). The patient also had some dental implants that replaced teeth that had been extracted due to vertical fractures. Although the primary concern for this patient was her dissatisfaction with the color and overall appearance of her smile, she also admitted suffering from tension headaches, grinding her teeth, and an inability to freely open and close her mouth.
|Figure 1. Preoperative facial view.|
|Figure 2. Pre-op retracted view.||Figure 3. Pre-op maxillary occlusal view.|
A thorough examination was performed, which included taking a full series of digital photos and radiographs, as well as obtaining impressions and pouring study models. In addition, a centric relation (CR) bite and face-bow transfer were done.
The clinical findings and mounted models were reviewed, ultimately indicating that the patient’s envelope of function was restricted, while continuous wear led to decreased vertical dimension of occlusion (VDO).3 Therefore, to determine if the VDO could be increased, a diagnostic wax-up (3D White Wax-Up [Arrowhead Dental Laboratory]) was requested and fabricated by the dental lab team. In the wax-up, the VDO was increased by 1.0 mm. Also, based on information gathered from the initial consultation and digital images, it was determined that the maxillary central incisors could be lengthened by 1.3 mm to improve the aesthetics. Additionally, the diagnostic wax-up also demonstrated that canine guidance in lateral excursions could be restored by lengthening the canines.4 There was some wear evident in the lower arch. In this case, the patient would be treated in 2 phases. The maxillary teeth would be prepared, provisionalized, and restored in the first phase. The mandibular teeth would also be prepared and provisionalized in this first phase of treatment and then fully restored at a later date. The clinical and lab protocol described below focuses on the first phase of treatment.
Based on the diagnostic wax-up (Figure 4), it was determined that restoring the entire maxillary arch would improve smile aesthetics and correct any functional issues. The final treatment plan would consist of crown restorations from teeth Nos. 2 to 15 in the upper arch; teeth Nos. 14 and 15 were implants and would also require custom abutments.
|Figure 4. Digital view of the wax-up.||Figure 5. Virtual design of the open bite in the 3Shape software.|
|Figure 6. The IPS e.max ZirCAD (Ivoclar Vivadent) monolithic zirconia restorations were tried on the model.||Figure 7. View of the custom abutments required for the implants for teeth Nos. 14 and 15.|
|Figure 8. Postoperative retracted view of the monolithic zirconia restorations.||Figure 9. Post-op maxillary occlusal view of the restorations following cementation.|
|Figure 10. Post-op facial view of the definitive restorations.|
The material of choice for these crown restorations was a zirconia material (IPS e.max ZirCAD [Ivoclar Vivadent]) that combines excellent flexural strength and fracture toughness with aesthetics that will meet the demands of a full-arch clinical case such as the one presented here.5 With full-contour IPS e.max ZirCAD restorations, 2 methods of achieving the desired shade are available: (1) the IPS e.max ZirCAD brush infiltration technique, and (2) the Zenostar staining technique. Six pre-shaded zirconia blanks (pure, light, medium, intense, sun, and sun chroma) form the basis for reproducing a patient’s natural dentition.
Clinical Treatment Begins
Treatment was initiated after obtaining informed consent from the patient. The patient was anesthetized, and then the existing crown restorations were removed. A single-component, light-cured universal adhesive for direct and indirect bonding procedures (Adhese Universal [Ivoclar Vivadent]) was applied according to the manufacturer’s protocol and cured using an LED curing light (Bluephase Style [Ivoclar Vivadent]). Then self-curing composite core build-up material with a light-curing option (MultiCore Flow Light [Ivoclar Vivadent]) was placed for the build-ups on any teeth requiring cores. To ensure adequate reduction for the full-coverage monolithic zirconia restorations, the entire maxillary arch (teeth Nos. 2 to 15) was prepared using a clear reduction guide (Arrowhead Dental Laboratory) and a coarse grit chamfer diamond bur (Komet). A full-arch impression was taken using PMMA custom trays (Instant Custom C&B Trays [Good Fit Technologies]). The proprietary polymethyl methacrylate material becomes adjustable when heated in boiling water, allowing the trays to provide an efficient way of capturing a dimensionally accurate impression with uniform impression-material thickness. After being shaped and fitted to the patient’s maxillary arch, the tray was loaded with heavy and light polyvinylsiloxane impression materials (Panasil [Kettenbach LP]), and a full-arch final impression was taken.
Next, a bite relations jig was first tried in the patient’s mouth, after which a medium-body impression material (Panasil) was placed into the relations jig and seated onto the preparations. The patient then bit into the relations jig until reaching the vertical stops, and the material was allowed to set.
Instructions for fabricating the definitive restorations (eg, size, shape, color), bite wax-up models, and other records taken were forwarded to the dental laboratory team. Also, a stump shade of the prepared teeth was taken to assist the lab team in creating natural-looking restorations.
To create the provisional restorations, Sil-Tech (Ivoclar Vivadent) impressions were taken of the 3D White Wax-Up. After setting up, the Sil-Tech stint was then loaded with a multifunctional acrylic composite temporary crown and bridge material (Visalys [Kettenbach LP]) (shade B1) and placed on the patient’s prepared teeth and allowed to set. Upon removal, trimming burs (Komet) were used to trim the provisionals. Next, a desensitizer (Telio CS Desensitizer [Ivoclar Vivadent]) was painted on the tooth preparations and dried; then a noneugenol cement (Temp-Bond Clear [Kerr]) was used for seating the provisionals. Home care instructions for maintaining the provisionals (including use in eating, speaking, and biting) were provided to the patient.
The provisional restorations were intended to provide the patient with an opportunity to preview the proposed size, shape, color, and position of the planned definitive restorations. (As previously mentioned, as a part of the first phase of treatment, the lower teeth were also prepared and provisionalized, but this is not shown in the photos accompanying this case report article.) After a few weeks, the patient returned to the office to share her assessment of the provisional, specifically regarding aesthetics, phonetics, and bite. She expressed excitement and confidence with the improved aesthetics of her smile and her overall younger and happier appearance. Additionally, she indicated that her TMJ and bite discomfort had resolved.
Because the provisionals did not require any adjustments or modifications, the laboratory was instructed to fabricate the definitive restorations based on the previously-returned wax-up.
The appointment for the delivery of the final restorations was scheduled for 3 weeks after the provisionalization appointment.
The 3D White Wax-Ups were digitally scanned (3Shape). To facilitate selection of the ideal arch form, tooth size, and occlusion, these scans would be used with a library of teeth included in the restoration design software (3Shape) (Figure 5). Once the proposed restorations were designed, they were emailed to the practice using 3Shape Communicate. To ensure an ideal aesthetic outcome, any required adjustments in tooth shape or contour were then shared with the laboratory’s technical advisor. Milling was initiated upon confirmation and approval (Figures 6 and 7). The finished case was then sent to the dental office.
The patient was anesthetized, after which a pneumatic crown remover (Dent Corp) was used to remove the provisional restorations. Residual provisional cement was removed, and chlorhexidine 2% (Consepsis [Ultradent Products]) was used to clean the preparations. The custom abutments for teeth Nos. 14 and 15 were inserted and torqued to 25 Ncm, and the access openings were sealed with Teflon tape.
To enable the patient to evaluate and subsequently approve the aesthetics and feel of the final monolithic zirconia crown restorations, they were tried in, and she was given a mirror to evaluate them in place. The restorations were also checked to ensure the accuracy of marginal fit and contour. After securing the patient’s approval, the definitive restorations were removed, and the cementation protocol was initiated. The intaglio surfaces of the restorations were cleaned using a universal cleaning paste (Ivoclean [Ivoclar Vivadent]). This product is specifically designed to remove contaminants from prosthetic surfaces after intraoral try-in. Creating a clean and debris-free restorative surface by applying the cleaning paste to the internal aspect of the restorations and then rinsing would help to enhance the bond strength between the restorations and the selected adhesive cement.
The preparations were also cleaned and dried, and a pen-like dispenser (VivaPen [Ivoclar Vivadent]) was then used to apply the selected universal adhesive bonding agent (Adhese Universal [Ivoclar Vivadent]) to the teeth. In this case, the single-component adhesive was used in self-etch mode, and it was cured with the LED curing light for 10 seconds per tooth.
To seat the restorations, a neutral shade of dual-curing adhesive resin cement (Variolink Esthetic DC [Ivoclar Vivadent]) was selected based on several advantages reported by the manufacturer (natural fluorescence, enhanced radiopacity, easy removal of excess, and exceptional shade stability). Once the cement was loaded into the internal aspect of the restorations, the crowns were seated onto the preparations, beginning with the central incisors (at the midline), then proceeding distally. This prevented the restorations from canting during placement. As seating continued, each restoration was secured until all crowns were placed, after which all restorations underwent the final light-curing. The patient’s occlusion and contact point positions were verified using an objective occlusal analysis system (T-Scan [Tekscan]) to help ensure the long-term stability and function of the restorations. The completed case can be seen in Figures 8 to 10.
Many dentists and their dental laboratory teams are faced with the challenges associated with treating patients with high aesthetic and functional expectations. Fortunately, they can overcome many of these challenges by incorporating digital treatment planning in order to efficiently achieve predictable outcomes using innovative restorative materials and effective fabrication and clinical techniques. Doing so will help the restorative team succeed in providing patients with restorations that demonstrate proper form, function, and aesthetics and contribute to improved oral health.
The author would like to thank the team at Arrowhead Dental Laboratory (Sandy, Utah).
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- Lerner J. A systematic approach to full-mouth reconstruction of the severely worn dentition. Pract Proced Aesthet Dent. 2008;20:81-87.
- Saratti CM, Del Curto F, Rocca GT, et al. Vertical dimension augmentation with a full digital approach: a multiple chairside sessions case report. Int J Comput Dent. 2017;20:423-438.
- Park JH, Kim JE, Shim JS. Digital workflow for a dental prosthesis that considers lateral mandibular relation. J Prosthet Dent. 2017;117:340-344.
- Vichi A, Carrabba M, Paravina R, et al. Translucency of ceramic materials for CEREC CAD/CAM system. J Esthet Restor Dent. 2014;26:224-231.
Dr. Nazarian maintains a private practice in Troy, Mich, with an emphasis on comprehensive and restorative care. He is a Diplomate in the International Congress of Oral Implantologists and is the director of the Ascend Dental Academy in Austin, Texas. Dr. Nazarian has conducted lectures and hands-on workshops on aesthetic materials and dental implants throughout the United States, Europe, New Zealand, and Australia, and his articles have been published in many of today’s popular dental publications. He can be reached at (248) 457-0500 or at the website aranazariandds.com.
Disclosure: the author reports no disclosures.