Dr. James L. Cassidy, Jr. - a Dentist in Macon, Georgia

News & Press

The Difficult Combination Fixed/Removable Care
Dental Economics - December 1995
by James L. Cassidy Jr., DMD

The Geriatric Patient

With the increasing age of our patient population and the success of our dental predecessors in educating, motivating and maintaining the dental patient, a large number of these older patients now require restoration of the masticatory system. Our responsibility is to use those remaining healthy structures, hard and soft, to restore the system as close to ideal as possible. My concern is that the techniques and processes that are time-tested and predictably successful are becoming a lost art.

The Case Study

Patients bring us varied problems and concerns. It is not enough to patch and watch as the system falls apart (Figured 1 and 2). This patient has received much dentistry over the years, yet it has been done in a very reactive way. The best way is to be proactive in your practice:

Conduct a comprehensive exam that allows you to examine thoroughly every structure and its interrelationship to all other structures.
Locate, verify and accurately record centric relation, which is the key element in the ability to choose the response to the patient’s condition.
Determine the incisal-edge position and lip-closure path, which is the third leg of the tripod created by the two condyles and the anterior teeth.

Begin With the End in Mind

The process of diagnosis and treatment-planning is the mental visualization in planning and sequencing the steps necessary to accomplish the end product. Those teeth that cannot be saved should be removed from the diagnostic models by sawing them off with a die saw. Now, a clearer picture of what you have to work with is before you (Figure 3).

The key tool in the visualization process is the diagnostic wax-up, which allows the dentist, laboratory technicians and patient to see the end product before starting. The wax-up either can be performed by the lab technician or by the commercial lab, using Ivory Sculpting Wax made by Black Marlin Dental. In either case, the five requirements of occlusal stability, as outlined by Dr. Peter E. Dawson, must be adhered to and the esthetics checklist should be used as a guide in the process. The beauty of the wax-up is that in using the Siltec putty (by Williams Ivoclar) technique, the wax-up becomes a tool for the fabrication of the provisional restoration that simulates the final product.

Put First Things First

Planning and organization absolutely are necessary. Planning turns the most complicated case into a routine case. A system by which all cases are sequenced allows all parties to know the next step. The best way to keep first things first is to perform all preliminary mouth preparations prior to starting the restorative phase - those procedures bring perio, endo, oral surgery and orthodontics, all of which can be accomplished in the provisional stage. In this case, the teeth are removed and provisionals are placed. A provisional partial also is placed in the maxillary arch (Figure 4). The lower teeth are prepared and the prefabricated post is removed from tooth #22 by using a Dentsply Cavitron P-10 tip, placed against the post (Figure 5), until the post starts to move; then it is removed. We have found this to be the least traumatic technique for post removal. The lower provisionalized, and the existing partial’s place of occlusion is corrected using Duracryl cold-cure resin (Figure 6). The provisional phase is started. Now, end on Tooth #3 and perio grafting on the lingual of #22 and #27 can be completed. All the while, the patient’s provisionals will stimulate the final product.

Think Win, Win

You must take the attitude of mutual benefit to the patient, but also to the provider. This comes in the form of financial remuneration, as well as the knowledge that you have done a great job. The patient benefits by the ability to function comfortably and by a better appearance. During the healing provisional phase, the patient has the opportunity to give feedback and more clearly define his/her expectations, so we may address all concerns. With this attitude, a true win-win situation exists.

Understanding the Patient’s Concerns

Many removable-partial wearers want to get rid of that old, irritating partial, but do not realize there is any alternative, or they automatically think implants are the only way to be comfortable. The principles of partial-denture design should be adhered to in the fixed-removable case, and the patient should be educated to understand the benefit of the design.

The principles that must be followed are known as the Rules of Threes. In the design, there are three priorities which have three rules each.

Lateral stability – The partial cannot move away from the teeth and the teeth cannot move away from the partial.
Support – Teeth and tissue support the partial.
Retention – Use no frictional retention. Always engage the undercut.

Finally, the design should always be to save the teeth. The partial realizes he/she is not the typical dental office and your credibility rises. Today it is not enough to combine integrity and honesty; these must be combined with competence. When honesty and competence are combined the result is trustworthiness.

Ten Weeks Later

Ten weeks have passed and all preliminary mouth preps are completed.

Now is the time to select a shade. A denture-tooth shade should be selected and the denture teeth can be matched by the crown and bridge technician. This prevents a two toned case. Tooth preps are finalized and all records are made. An accurate facebow recording is taken using a Slidematic Facebow by Denar, and the only way to relay the necessary information to the laboratory is by the use of transfer bases, which allow the working die model and the approved provisional model to be interchangeable (Figure 7). Simply put, this is the only way to accurately communicate centric relationship and incisal-edge position to the laboratory specialist when there are no posterior teeth or stops of any kind. Final impressions are poured and models are mounted by the lab assistant. The case now is sent to the laboratory with a complete treatment plan outline and design. While in the laboratory, the communication between the removable technician and the crown and bridge technician is crucial in terms of setting denture teeth prior to attachment placement. This process cannot be rushed and in a top-quality lab, is performed with great care and concern; therefore, the patient’s provisionals must be very high quality to be able to last through the entire process.

With the crown and bridge completed, it is tried in and drawn in an alginate impression in a custom tray. Duralay dies are made and stone models are poured. Record bases and wax occlusal rims are made and contoured and the anterior teeth set at a subsequent appointment. This information now is sent to the laboratory specialist and precision partials are fabricated using the hybrid model of the actual crown and bridge and stone replica of the tissue. With this high level of accuracy and teamwork, you are able to complete the precision partials and have the D2.7 attachments processed by the laboratory (Figure 8).

By beginning with the end in mind, the process of insertion becomes the physical manifestation of the original vision presented to the patient (Figures 9 and 10).

*Please note that at this time, the figures mentioned in the above article are unavailable. We working to get the images posted for your better understanding of the case.