Fig. 4—Post-operative view of the bonded pressed ceramic veneers. The porcelain used in this case was Empress and a 01 ingot was used. The preparation depth was .7 mm but still well within the enamel.
Click here to enlarge imageThese first ceramic veneers were fabricated from feldspathic porcelain, although with the launch of IPS Empress 15 years ago, pressed ceramics became the most popular technique for fabricating ve-neers. In our laboratory today, 86 percent of porcelain veneers is fabricated from pressed ceramic and 14 percent is fabricated from feldspathic. However, there are certainly times when feldspathic ceramic restorations can be preferable to pressed ceramic restorations. Let's examine the two techniques and discuss a rationale for choosing one.
Advantages of pressed ceramic:
• Wear compatibility
• Increased translucency
• Ability to wax-up final contours prior to pressing
• Stronger than feldspathic
• More consistent results for the average ceramist
Advantages of feldspathic ceramic:
• Ability to mask out darker preps
• Less tooth structure removal (.3-.5 mm vs .6-.8 mm)
• More 3D appearance in thinner areas
• Ability to use same ceramic as in adjacent PFMs
• Ability to place different opacity levels within the restoration
Recommendations for pressed ceramic selection:
• When significant malposition exists in arch
• When significant increase in tooth length is desired
• When strength is of utmost importance
Recommendations for feldspathic ceramic selection:
• When minimal preps are desired due to patient concerns or minimal changes in size, shape and shade
• Diastema closures when shade is not altered significantly
• Teeth with minimal malpositions within the arch
• When adjacent teeth will have PFM restorations placed
Conclusion:
While either fabrication technique can be a viable solution for most ceramic veneer cases, there are distinct advantages and disadvantages to both techniques. The key to aesthetic success remains largely in the artistic capabilities of the ceramist. Materials and techniques work differently in different hands, therefore it is imperative to build a relationship with a laboratory that suits your needs both functionally and aesthetically. Consult with your laboratory regarding the materials they prefer on certain cases to achieve the most natural-looking result. Sending pre-operative, prep and provisional photographs and study models to act as guideposts for your laboratory will give you the best chances of creating the smile both you and your patient envision.
Dr. Michael DiTolla is director of clinical research and education at Glidewell Labs in Newport Beach, Calif., where he also teaches over-the-shoulder courses on topics such as aesthetic restorative dentistry. Dr. DiTolla also teaches a two-day, live-patient, hands-on laser-training course that emphasizes diode and erbium lasers. In addition, he teaches a two-day, hands-on digital photography course emphasizing intraoral and portrait photography, and image manipulation. More information on these and other courses can be found at www.ditollaseminars.com or by calling (888) 535-1289.