Milling and Try-in
IPS Empress CAD Multi shade A2 was chosen for the final restoration, which has a built-in shade gradient to match the contralateral central. It took approximately 7 minutes for the restoration to be milled with the inLab MC XL mill (Dentsply Sirona).
The sprue was removed and the restoration was tried in, checking for fit, esthetics, and marginal integrity (Figure 7). At this stage, desired refinements to the crown were done with a fine diamond bur. Once the final shape, emergence, line angles, and texture were satisfactory, the restoration was stained and glazed to match the appearance of the right central.
Cementation
Before cementation, the intaglio of the restoration were etched with 4.5% hydrofluoric acid etch (Ultradent) for 60 seconds, washed, dried, and silaned for 60 seconds. The enamel was selectively etched for 15 seconds, washed, and dried. The NX3 Nexus™ cementation system and OptiBond™ XTR bonding system (Kerr Corporation, www.kerrdental.com) were used to cement the restoration. The crown was carefully placed in the correct orientation. When the cement reached gel stage, the restoration was tack-cured for 2 seconds and the excess cement was removed with an explorer. All surfaces were then cured for 20 seconds each. The proximal surfaces were flossed and any remaining cement was cleaned up. Occlusion was checked and the margins were polished. The paste was rinsed and the immediate postoperative result was evaluated from the facial surface. The all-ceramic crown on the maxillary left central incisor was well received by the patient (Figure 8).
Final Thought
There are several ways to treat discolored teeth, which include neutralizing the stump with an opaque, using low translucency porcelain blocks, using high opaque cements, and increasing the spacer for the restorations. Clinicians must decide to use one or a combination of these techniques to ensure the best final outcome of masking the discolored tooth and creating the correct optical properties that match the contralateral tooth.
Additional Reading
• Ender A, Mehl A. Full arch scans: conventional versus digital impressions—an in-vitro study. Int J Comput Dent. 2011;14 (1):11-21.
• Fasbinder DJ. Clinical performance of chairside CAD/CAM restorations. J Am Dent Assoc. 2006;137 (suppl 1):22S-31sS
• Mehl A, Blanz V, Hickel R. A new mathematical process for the calculation of average forms of teeth. J Prosthet Dent. 2005;94(6):561-566.
• Poticny DJ, Klim J. CAD/CAM in-office technology: innovations after 25 years for predictable, esthetic outcomes. J Am Dent Assoc. 2010;141(suppl 2):5S-9S.
• Fasbinder DJ. Computerized technology for restorative dentistry. Am J Dent. 2013;26(3):115-120.
• Spear F. Restoring discolored endodontically treated teeth. Spear Education website. https://www.speareducation.com/spear-review/2014/02/restoring-discolored-endodontically-treated-teeth-case-1. Accessed March 1, 2016.
• Skramstad M. Choosing the correct block. Cerec doctors.com Magazine. 2014;54-59.
• Skramstad M. Taking anteriors to the next level. Cerecdoctors.com Magazine. 2013;30-31.
For more information, contact:
Pacific Dental Services
714-845-8500
http://pacificdentalservices.com
About the AUthor
Dhaval Patel, DDS
PDS®-Supported Owner Dentist
Roseville, California
