Preserve enamel and improve long-term success in minimally prepared porcelain laminate veneers
An interdisciplinary treatment approach for minimally prepared porcelain laminate veneers
Ultimate restorative success always begins with an accurate diagnosis and a carefully designed treatment plan, which often mandates an interdisciplinary approach. The goal of minimally prepared veneers is to preserve as much enamel as possible, because bonding to enamel is more predictable than bonding to dentin. Keeping the majority of the preparation in enamel has been shown to improve long-term success. This article emphasizes an interdisciplinary approach, minimally invasive treatment, and guided tooth preparations, based upon a digital smile design, a diagnostic wax-up, and a mock-up.
The porcelain veneer restorations were tried in with TR shade paste (RelyX veneer cement, 3M ESPE) to evaluate the margins, proximal contacts, tooth length and width, proportion, contour, smile line, symmetry, occlusion, and color. It is expected that with a precise impression, die-work, mounting, and provisional restorations as a reference, all these parameters will be adequately controlled in the final restorations.
After the patient approved the veneers, the rubber dam was placed and all the veneers were bonded using a total-etch technique and veneer resin cement in the following sequence:
The tooth preparations were cleaned with pumice and a webbed prophy rubber cup and air-particle abrasion was performed with 30-µ silica (Rocatec Soft, 3M ESPE).
The preparations were etched with 35%phosphoric acid (Scotchbond Phosphoric Etchant, 3M ESPE) for 15 seconds, rinsed, and coated with adhesive (Single Bond, 3M ESPE).
The veneers were etched with 5% hydrofluoric acid (Ceramic Etch, Ivoclar Vivadent) for 20 seconds, then rinsed and dried.
Ceramic primer (Monobond S, Ivoclar Vivadent) was applied for 60 seconds, the adhesive was applied on the intaglio (Single Bond), and the veneers were seated using a light-cured resin cement (RelyX veneer) (Figs 17a-17f).
Definitive photopolymerization was performed for 40 seconds facially and palatally, and the excess cement was re-moved with a #12 scalpel (Henry Schein; Melville, NY) (Figs 18-20).
An occlusal guard was fabricated and delivered to the patient at a subsequent appointment to provide nighttime protection for the new restorations.
Figures 17a-17f: Frontal views of bonding sequence.
Figure 18: Frontal view of veneers after bonding with resin cement.
Figure 19: Frontal view of final restoration in centric occlusion.
Figure 20: Final patient portrait.
Minimally invasive treatment continues to increase in popularity. A suitable environment must be created to achieve minimally invasive preparations without com-promising the outcome of the final restorations. This article has demonstrated the use of an interdisciplinary treatment-planning protocol to manage conservative preparations with pre-restorative orthodontic treatment. Digital smile design is a useful tool that allows precise clinical and laboratory evaluation, and serves as a communication tool with the patient and with the other specialists. The diagnostic wax-up, mock-up, and esthetic provisional restorations serve as consecutive, critical prototypes that communicate precise minimum tooth reduction and sufficient thickness to the technician in the creation of natural-looking restorations.