|
New Articles
|
October 2008 | Dental Lab Products
Bench Mastery Press success IPS e.max offers exceptional fit, strength and esthetics.
Restorations in the anterior region require exceptional fit, form, and natural-looking, seamless esthetics. Achieving these objectives when the restorations are supported by implants with metal abutments can be challenging. The restorative materials must blend with the adjacent natural dentition and successfully block out the underlying substrate. In cases where implant abutments must be restored in the anterior region with crowns that demonstrate true-to-nature optical properties, a combination of fluorapatite glass ceramic (IPS d.SIGN), pressable glass ceramic ingots (IPS e.max Press), and low-fusing nano-fluorapatite glass ceramic veneering porcelain (IPS e.max Ceram) can be used to produce exceptionally esthetic results. These materials collectively demonstrate lifelike translucency and brightness, as well as thorough masking capabilities suitable for concealing metal frameworks or implant abutments. Additionally, their respective physical characteristics make them optimal for the fabrication of single crowns in the anterior region. Case Presentation A 20-year-old man presented with an abscessed root tip of tooth No. 8. Five years earlier, he presented after an accident that left teeth Nos. 8 and 9 unrestorable. Tooth No. 9 was extracted and a bone graft placed for ridge preservation. Tooth No. 8 was ground off and saved in an attempt to preserve more bone. At the current presentation, the root tip of tooth No. 8 required extraction. Subsequent treatment included placing two regular platform fixtures (Nobel Biocare Replace Select). The surgeon used a “pedunculated flap” technique to build soft tissue. After 6 months of healing, an open tray, fixture-level impression was made for the fabrication of the definitive custom abutments and crowns. However, restorative challenges included asymmetric positioning and contours of the adjacent teeth and spacing. The following are the steps used to fabricate implant-supported restorations in this case. Laboratory Technique 01 Pour the impressions and fabricate and mount the master models (Fig. A). Because of the depth of the fixture heads, ovate contours were developed for tissue support and emergence profiles (Figs. B and C). 03 After metal finishing, opaque the abutments (Fig. E). In this case, the abutments were opaqued and subgingival contours and margins formed using IPS d.SIGN fluorapatite glass ceramic from Ivoclar Vivadent (Fig. F). 04 Wax the definitive crowns to full contour (Fig. G) and create an incisal matrix using Sil-Tech putty (Ivoclar Vivadent). 05 Cut back the wax patterns incisally and facially to allow sufficient room for layering of the veneering porcelain (Fig. H). 06 Sprue and invest the wax patterns for pressing (Fig. I). These crowns were pressed with medium opacity (MO) glass ceramic ingots (IPS e.max Press) to complement the opaqued metal abutment. Verify fit of the crowns on the abutments and master cast (Fig. J). 07 Internally stain the frameworks to create the desired esthetic and characterized effect (Fig. K). Dust the crowns with IPS e.max Ceram effect powder for a “wash” firing (Fig. L). 08 After firing, layer a combination of enamels and effect powders (Figs. M and N) using the Sil-Tech matrix to maintain the proper incisal edge position. Fire the crowns. 09 Fit restorations to master model using various diamond burs and wheels. Final contours are established at this point. After contours and function are verified, glaze the restorations. 10 Fit finished restorations to the custom abutments (Figs. O and P). Place restorations and custom abutments on the master model (Fig. Q). 11 Fig. R shows the try-in of the custom abutments. Fig. S shows the final restorations seated in the mouth after cementation. Fig. T is a retracted view.
|
|


Printer Friendly
Email Article









