Chinese philosopher Lao-Tzu wrote, “We mold clay into a pot, but it is the emptiness inside that makes the vessel useful.” Similarly, a dental implant may be produced on a CNC machine and placed in a surgery, but it is the empty space inside that makes it useful. The only reason the patient is receiving a posterior single implant is to provide support for a tooth. The truly relevant factor for the patient, restorative doctor, and dental laboratory technician is the empty but threaded space on the inside of the implant (Figure 10). What differentiates optimal from clinically acceptable is the positioning of the implant platform and the empty space inside of it to receive the restoration, accept a lifelong load transfer, and maintain a biologic interface with soft tissue and bone. Observing available bone, soft tissue depth, and restorative emergence from the implant or abutment and subsequently positioning within the occlusal table facilitates optimal implant positioning. This has become practical enough to provide on a routine basis for the additional information it provides.
Any new technology must be easy to understand, practical to implement, and cost-effective by returning either time savings or increased short- or long-term revenues for the expenditure. It only requires 5 minutes total for a surgeon to plan the single-tooth restoration using this method while effectively producing twice the amount of beneficial information on the patient’s behalf. No additional time is required if the plan includes a surgical template. Depending on experience and other conditions, the conversion of the plan into a surgical template can provide an additional return in time savings and routinely straightforward results with more routine restorative and laboratory fees.
There are documented benefits of efficiency comparing digital and analog restorative delivery.16 Utilization of diagnostic benefits integrated with implant placement, abutment and restorative design, and production show the potential to bring these efficiencies to an even higher level without any compromise or even improvement of results. In addition, the laboratory invoice will tend to be less with a crown/abutment placed directly to the implant compared to an abutment of titanium or zirconia and a separate cemented crown. Think of the restoration as a “one-piece crown/abutment complex,” taking the virtual planning through computer milled production into reality.
A full-contour zirconia implant restoration provides a predictable and straightforward restorative solution for replacement of posterior single teeth. To design the desired restoration and import the proposed design into the preoperative scan, along with soft tissue information, provides significant added value from the scan for the patient and treatment team. There are many opportunities for using integrated and combined digital processes to facilitate this process. For patients receiving scans, having optimal restorative planning preoperatively superimposed onto the scan can contribute toward optimal results on a routine basis beyond utilization of a bone-only scan.
This technique eliminates the biologic concerns of inadequate cement removal while providing a lower dental laboratory investment without compromise. Optimal implant placement to support this restorative design relative to axial trajectory, soft tissue emergence profile affecting implant seating depth, and the available bone is now possible to more fully utilize the CT-scan exposure on the patient’s behalf. These informative planning images can be beneficial for both patient communication and discussion by the treatment team.
The author wishes to thank Momo Vasilic, CDT, for his support in the planning and restorative process.
Richard M. Sullivan, DDS, is an employee of Nobel Biocare, and is a manufacturer and developer of the products and software used in this article.
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