Robert Kreyer, CDT, outlines the considerations for developing a technical diagnostic plan

In this column, I will discuss technical diagnostics and its relationship to providing predictable implant-complete prosthetics. Technical diagnostics is the clinical ability to understand the prosthetic variables involved and visualize the finished prosthesis before treatment begins. Once the clinician and technician can visualize the end prosthetic product, we can then start working back, developing a plan to create the desired results.

To have consistent success with an implant-retained or supported prosthesis, we must begin with “technical implant diagnostic prosthetic planning.” Implant prosthetic treatment planning is the aspect of “complete prosthetics” that involves the design and manufacturing processes for removable or fixed implant prostheses in the oral environment. To achieve optimal outcomes, implant or complete prosthetics should be treatment planned and designed with the goal of replacing lost bone, tissue, and dentition, while restoring function, esthetics, and phonetics. With the objective of providing optimal treatment for an edentulous patient, we must develop an implant prosthetic treatment plan.

Because dental clinicians and technicians have a symbiotic relationship, excellent communication and collaboration between the implant prosthetic team is essential to achieving consistent success. Understanding clinical and technical implant prosthetic variables as they relate to biology and biomechanics is the key to providing optimal treatment and exceeding expectations. As clinicians and technicians, we must be very careful not to confuse esthetic desires with the art of anterior esthetics. It is possible to deliver a younger natural smile while maintaining an age-appropriate objective. It is our responsibility as professionals to provide these prosthetic options to an edentulous patient.

In today’s economy, prosthetic dentistry is seeing a resurgence of edentulating patients and is designing more complete, immediate, provisional dentures. With this immediate-complete denture prosthetic treatment, we must plan for the future possibility and options of implant placement for transitioning into implant-retained, then implant-supported prosthetics. Denture tooth occlusion must be designed and created taking into consideration potential residual ridge resorption and implant placement so the occlusal vector forces are directed toward the long axis of an implant body. Depending on surgical procedures such as bone grafting or socket augmentation, which positively affect postsurgical ridge resorption, a second provisional could be part of the implant prosthetic plan. If a second complete prosthesis is made, then improved anterior esthetics and functional denture occlusion are worked out in this second phase of treatment. This second prosthesis can also be loaded when the clinician or surgeon determines it is the proper time to do so. The second transitional implant prosthesis then becomes a guide to designing a definitive implant-retained or supported overdenture with implant-protected occlusion.

For any prosthetic work, the technician must communicate his/her prosthetic techniques, including the materials and equipment used during the design and manufacturing process. This communication of understanding needs and expectations will make the prosthesis successful. Clinicians and technicians have a coexisting relationship with the goal of providing optimal treatment for complete denture prosthetics. Through working in a clinical and technical collaborative relationship, the patient benefits from increased communication and a predictable prosthetic result.

Expectations and desires

Understanding a patient’s expectations and desires is critical to success with implant overdenture prosthetics. How can one know how to properly design an anterior smile for complete implant overdentures without understanding a denture wearer’s desires and expectations? Unnatural esthetics in the smile zone is one of the main reasons complete denture prosthetics fail. Not fulfilling the esthetic expectations will certainly result in an unhappy patient and a definite remake. Removable implant overdenture wearers look at their complete prostheses when they smile in the mirror, while cleaning their overdentures, and before placing them in their mouths. If a patient is not satisfied with the esthetics and appearance of an implant-overdenture prosthesis, then he/she will not smile with confidence, thus affecting self-esteem and confidence. A very esthetic and functional complete overdenture prosthesis helps to restore self-confidence while enabling a denture wearer to enjoy the blessings of life such as eating, smiling, speaking, laughing, and singing.



Diagnostic prosthetic options

The process of matching possible treatment options with a patient’s needs requires systematically arranging the clinical and technical procedures in order of priority while developing a logical or technically necessary case sequence plan. Figures 1-10 are photos of various prosthetic cases illustrating different diagnostic options.

Provisional prosthetics

A provisional is a complete denture (CD) or removable partial denture (RPD) to be delivered immediately after extraction of teeth. This type of dental prosthesis is also referred to as a transitional or interim denture. Transitional overdentures can be loaded with implants during treatment. Provisional prosthetics is an excellent diagnostic tool for understanding occlusal and esthetic expectations before the definitive prosthetic is designed.

Radiographic template

A radiographic template is a guide derived from a diagnostic wax-up or tooth arrangement and worn during the radiographic exposure to relate the tooth position to the anatomical structures. It assists in the diagnosis and planning phase for dental implants.

Surgical guides

A surgical guide is derived from the diagnostic wax-up, tooth placement, or CBCT scan to assist during surgical placement of dental implants. This removable prosthesis is designed using either model- or computer-based technology, incorporating sleeves for pilot hole or implant placement. These sleeves dictate drilling position and angulation of implant placement during surgery.

Definitive prosthetic options

Definitive dentures
Definitive dentures are either a CD or RPD that is designed for long-term use according to biology and biomechanical considerations of the oral environment. The three principles that guide us in the design of complete denture prosthetics is support (bone and tissue), stability (occlusal forces), and retention (fit of base to tissue). The most important factor to denture wearers is esthetics. By understanding a denture wearer’s desires, we are enabled to exceed their esthetic expectations.



Implant prosthetics

The objective of implant prosthetics is to improve the quality of life for a compromised completely or partially edentulous patient while using dental implants to increase support, stability, and retention in a removable dental prosthesis. This specialized field of prosthetic dentistry is composed of three implant prosthetic options: implant-retained prosthetics, implant-supported prosthetics, and implant hybrid prosthetics.

Implant-retained overdentures

The implant-retained overdenture derives its support from a combination of intraoral tissues and dental implants. An implant-retained overdenture is always removable, and can be designed for complete or partially edentulous patients.

Implant-supported overdentures

An implant-supported prosthesis derives its entire support from dental implants. This type of restoration may be fixed (screw retained) or removable (attachment retained). Only a clinician can remove a screw-retained implant-supported overdenture, compared to an implant-supported attachment- retained (fixed-detachable) prosthesis that can be removed by the patient or clinician.

Hybrid implant prosthesis

The term “hybrid” implies a combination of a metal superstructure, such as a virtually designed milled or cast bar with prefabricated denture teeth, and heat-cured base acrylic resin wrapped around a bar. Hybrid prostheses are totally implant supported and screw retained. This type of implant prosthesis is fixed and can be removed only by a clinician. It is through this case planning process that you will develop diagnostics according to your clinical objectives and will thereby exceed your patient’s expectations and desires.

Bio

Robert E. Kreyer, CDT, is a member of the American Prosthodontic Society and is the author of numerous published articles on removable prosthetics. Robert is a registered continuing education (CE) provider for the Dental Board of California and the National Board of Certification in Dental Technology. Robert is the Director of Removable Prosthodontics for MicroDental in Dublin, CA, and he teaches CE courses in removable prosthetics for Ivoclar Vivadent at the Implant Esthetics Center of Excellence (IECE) in Sarasota, FL. He can be reached at www.PersonalizedDenture.com