A recent article in The Journal of Prosthetic Dentistry indicates that at least for the next 20 years, the number of edentulous patients will rise and the total number of edentulous arches will approach the 60 million mark in the United States alone.1 There are wide clinical, economic, and social variations in the edentulous population. Traditional conventional methods are not flexible enough to adequately address all these variations. There is a growing need in complete denture prosthodontics for an effective and simplified denture technique.
Figure 1. The Denture Tray.
Figure 2. Overextensions are trimmed.
This technique uses The Denture Tray (Dental Moldable Devices) (Figure 1), a thermoplastic impression tray that comes in the form of maxillary and/or mandibular complete dentures. During the first appointment the trays are customized by trimming, heating, and adapting either on a model or directly in the mouth. They are then border molded and the final impressions are taken. In the next step we use the trays for an initial try-in to evaluate aesthetics, tooth position, and phonetics. This technique totally eliminates the need for wax rims and record bases since the trays can be used for recording maxillo-mandibular relations, as well as selecting tooth mold and shade. They are then sent to the laboratory to be poured and articulated with all desired changes duly noted on the prescription. The lab then uses them as a guide to provide a custom setup/wax try-in or finished denture for the second appointment.
FIRST APPOINTMENT: CUSTOMIZE TRAY
The trays are available in four different base size, tooth mold, and setup configurations. The first step is to select the tray that most closely approximates the residual ridge in shape, and size and customize it. While this can be done intraorally, we find it easier to use preliminary models. Once the trays have been selected, all overextensions are trimmed using scissors or a bur (Figure 2). The trays are then placed in hot water (170°F) and adapted to establish a close fit. These customized impression trays will be used in the form of maxillary and mandibular complete dentures to make final impressions.
|Figure 3. Trays adjusted to allow enough room for border moldings.||Figure 4. Peripheral borders now developed by having patient suck on index finger.|
|Figure 5. Maxillary border molding completed.||Figure 6. Tongue protuded straight to the left and the right.|
|Figure 7. Mandibular border molding completed.||Figure 8. Maxillary final impression.|
|Figure 9. Mandibular final impression.||Figure 10. Desired changes are marked on the tray and indicated on the prescription.|
The trays are tried in and adjusted to allow enough room for border-molding material which is applied to the maxillary tray (Figure 3). We prefer a functional wax (Adaptol, Jelenko), but any material of choice can be used. Peripheral borders are developed by having the patient suck on the index finger and moving the lower jaw from side to side. Holding the tray in place, the upper lip is massaged in a downward motion (Figures 4 and 5).
|Figure 11. The interpupillary and alatragus planes are adjusted as necessary.||Figure 12. Lip support is evaluated and any changes in tooth position are indicated on the prescription.|
|Figure 13. The Denture Tray serves as a three-dimensional mold guide, which helps prevent patient dissatisfaction with tooth selection in a wax try-in stage.||Figure 14. Grind teeth to increase freeway space, or add wax to decrease it.|
|Figure 15. Inaccurate bite registrations due to improperly contoured wax rims and loose-fitting, unstable record bases are eliminated.||Figure 16. Left–wax try-in; Right–finished denture.|
|Figure 17. Custom denture delivery at second appointment.|
The unique design of these trays actually allows us to do a preliminary try-in during the first appointment! A major advantage of this technique is the elimination of bulky wax rims and poor-fitting record bases. Instead of wax, we work with the acrylic tooth forms that are an integral part of The Denture Tray. The upper tray is inserted and the midline and incisal length are evaluated. Any desired changes are clearly marked on the tray and indicated on the prescription (Figure 10). The interpupillary and alatragus planes are observed and adjusted if necessary by grinding the teeth or by adding wax (Figure 11). Lip support is evaluated and any changes in tooth position are indicated on the laboratory prescription (Figure 12). Minor changes can be made by reheating and repositioning the teeth.
It is often helpful to use the patient’s existing denture as a guide to establish the vertical dimension of occlusion for the new prosthesis. The desired vertical dimension of occlusion is now marked on a tongue depressor. The trays, having been stabilized by the impression material, are inserted and adjusted to the new vertical dimension. To increase freeway space we grind the teeth; to decrease it we add wax (Figure 14). Having the benefit of tooth forms instead of wax rims is an advantageous feature that allows us to more accurately evaluate vertical dimension using phonetics. The patient counts from 60 to 70. Contact during these sibilants indicates insufficient freeway space. Spacing in excess of 3 mm often indicates excessive freeway space. Attempting to make these judgments by having the patient speak with wax rims and loose bases is at best problematic.
The patient is guided into centric relation and the position is recorded at the desired vertical dimension of occlusion using Aluwax (Aluwax Dental Products Company). Another major advantage of this technique is using stable final impressions and acrylic tooth forms. Two of the most common causes of inaccurate bite registrations are improperly contoured wax rims and loose-fitting, unstable record bases. Because we no longer use either of these, this technique totally eliminates these problems (Figure 15).
Since we were satisfied with all the results achieved during the first appointment, we elected to have the dentures processed and finished. The dentures are delivered during this second appointment. Although the ultimate goal of using this new technique is to deliver complete dentures in two appointments, we recommend utilizing wax try-ins until you are totally familiar and comfortable with the procedures (Figures 16 and 17).
The need and demand for complete dentures will increase over the next two decades as the baby boom generation matures into the upper age groups.1 This, coupled with the fact that complete dentures have been de-emphasized in dental education programs as well as in many private practices, amplifies the need for an effective, expedited, more economical approach to complete denture fabrication. We have found that this new technique meets all of these requirements. It significantly reduces appointment time, helps to achieve more accurate models and articulations, and enhances the chances of patient satisfaction and clinical success.
- Douglas CW, Shih A, Ostry L. Will there be a need for complete dentures in the United States in 2020? J Prosthet Dent. 2002;87:5-8.
Dr. Ginsburg is a prosthodontist practicing in Boston. In addition to his extensive international lecture background he was a member of the Complete Denture Faculty at the Tufts University School of Dental Medicine for many years. He has developed and patented several products and has collaborated with some of the major dental companies in the United States and Europe. He can be contacted at (617) 330-8971.
Disclosure: Dr. Ginsburg is the co-developer of The Denture Tray and a consultant to Dental Moldable Devices.
Dr. Cavalier is currently engaged in the full-time practice of dentistry in Boston. For more than 20 years he taught at Tufts University School of Dental Medicine. Dr. Cavalier helped author the text utilized by the students in the discipline of Complete Denture Prosthodontics within the school. He has also acted as the department chair for the Department of Complete Denture Prosthetics.
Disclosure: Dr. Cavalier is the co-developer of The Denture Tray and a consultant to Dental Moldable Devices.