The Tissue is the Issue. How to transfer the emergence profile from the provisional to the final restoration.

 

Lars Hansson CDT, FICOI

 

Successful osseointegration and function have traditionally been the main goals for implant therapy. However, successful osseointegration does not automatically lead to an optimal esthetic result, and inadequate treatment planning may severely compromise the esthetic result regardless of biologic and functional integration. Exact replication of the natural  dentition, maintenance of a harmonious soft and hard tissue architecture, and imperceptible integration of the final implant prosthesis are among the challenges of modern implant dentistry.

Provisional implant-supported  restorations play a key role in achieving those goals, and many techniques have been described to maximize the appearance of the tissues around implants through alteration of the provisional restoration. The ideal emergence profile and morphology of the peri-implant soft tissues should be determined during the preprosthetic laboratory phase and then modified chairside. A proper impression technique is key for an accurate transfer of the peri-implant tissue contour from the patient’s mouth to the definitive cast.

 

A conventional impression coping cannot support the marginal soft tissue sculpted by the provisional restoration. Therefor a customized impression coping is made. Since the provisional restoration has sculpted the tissue we now need to transfer this to the final impression by attaching a laboratory analog to the provisional. The analog and the provisional are then placed in a cup filled with polyether impression material. The corresponding impression coping is then screwed to the implant analog embedded in the polyether cervical contour mold. A flowable composite is injected around the coping to obtain and exact replica of the cervical contour of the provisional restoration. The final impression is taken and the accurate cervical contour is now transfered to the final cast and the final abutment  can be fabricated. The final abutment can now be fabricated in Titanium , Zirconium or custom cast abutment.

 

 

 Fig 1 The provisional abutment and crown are connected  to and implant analog and embedded in the impression material to duplicate the cervical aspect of the restoration

 

Figure 1

 

 

Fig 2 Close-up view of the trimmed mold.

 

Figure 2

 

 Fig 3 A standard impression coping is screwed to the implant analog fixed in the impression material. Flowable composite resin is injected into the space between the coping and the impre ssion material.

 

Figure 3

 

 

 Fig 4 After light curing , the customized impression coping is removed and can be used to accurately transfer the emergence profile of the provisional crown

 

Figure 4

 

 

Fig 5 Customized impression coping in place ready for impression and emergence profile transfered to the laboratory technician to fabricate the final restoration.

Figure 5

 

Figure 6 Showing the impression coping seated and the emergence profile .

Figure 6