"Octopus Tentacles"
For Better Retention of Prosthetic Appliances

By David Block, President, CEO

Ask yourself; how much technological advancement has been made in full dentures in modern times?

"Well, compared to what? Since they made George Washington's teeth, using hinges in the back?"

The successful wearing of prosthetics depends upon the awesome tenacity of the patient. In almost every instance, if the dentist who delivered the dentures, and the technician who fabricated them, don’t hear from the complaining and unhappy patient, then that was a success - or was it? Think about it - how would you handle a new set of dentures? You would experience looseness, tipping, increased saliva flow, clinging and sticking food, passages of food under the bases, gagging, tongue crowding, speech deflection, and psychological adjustments due to appearance.

In a recent survey, it was found that a majority of dental schools only require one or two full dentures to be made and delivered in order to graduate. (There are some exceptions to that requirement.)

43,000,000 people in the U.S. are edentulous or partially edentulous. The actual insurance tables are rising rapidly. Fifty percent of the population never sees a dentist in their lifetime. Dentally ignorant people will ignore any warning signs until it is too late. This shows the need for full and partial dentures, now and in the long-term future!

Progressive thoughts must prevail - both from the dentist and the laboratory in order to compete and be financially successful. Both must begin to concentrate on advanced procedures, techniques, and the patient's awareness regarding comfort and esthetics.

A basic concern of an edentulous patient is retention of their dentures. This has lead to the growth of a very large "Denture Adhesive" industry. Look in any drug store. The basic retention needs of denture wearers, has led to considerable experimentation and research efforts trying to perfect dentures that compensate for natural tooth loss, and to enhance retention by any means possible. Attachments, magnets, clasps, etc., have all been tried with minimal success. The use of a soft material denture lining, surfaced with multiple miniature suction cups, satisfies the requirements of retention and stability. However, the proficiency required in laboratory fabrication skills, have kept this technology from gaining acceptance in the industry. Dentists (and patients) loved it, laboratories hated it, and let's face it, if the labs won't or can't make it, then a dentist can't prescribe it.

History of Experimental Dentures

Patents on suction cup dentures were issued to J. Spyer and R.S. Ingalls in 1885. These patents covered multiple projections on the tissue surface of the denture. A patent was issued in 1907 to G.W. Morgan for suction cavities in a soft rubber sheet. A large number of other devices have been proposed, but all of them failed to meet the prerequisites of simplicity, comfort, permanency, tissue tolerability, practicality, and aesthetics.

Since 1992, I have experimented in our research and development department at Aesthetic Laboratories. We have tried attaching individual suction cups, strips of suction cups, and group sections of cups to dentures. These were made from various materials, including latex rubber, polyethylene, vinyl polymers, soft methyl meth-acrylates, mercaptan, rubbers, and silicone elastomers. Most of the materials were too hard, or would not remain soft and pliable. All of these materials, except the silicones, present difficult technical problems, which add excessive costs to the prosthetic appliance.

The lining material used in all of these trial applications was Silastic, a high molecular weight dimethylopolysiloxane polymer. Sufficient clinical evidence of its’ toleration by oral tissue was available, justified our use in constructing more than 50 suction cup dentures. Some of the problems encountered could only be solved by trial and error. Among those problems were the size and shape of the suction cups.

I first attempted to duplicate the typical shape of the suction cups, but the construction of such a shape proved to be both difficult and expensive. The cups settled into the tissue, very soft-tissue tended to conform to the shape of the cups, or both occurred simultaneously. Further testing indicated that the best results were obtained using a cup shaped with straight sides and a tapered interior. The ideal angle of the tapered sides proved to be 12.5 degrees outward, similar to those of a typical suction cup. This degree of taper allows for the correct resiliency of the silicone material, so that it "gives" and conforms to the contacting tissue rather than acting as a repelling force.

Solves Extreme Resorbed Ridges

The chief indication for a denture with multiple suction cups is the patient’s desire for extra retention and stability of his or her dentures. Many patients have extremely resorbed ridges and cannot master the use of dentures, let alone retain these prosthetic appliances in their mouths. This "Multi-Cup" technique (multiple suction cups) addresses their problem, as well as knife-edge or flat ridges, and can be made with or without palates.

The dentist’s problem has been to find a lab that even knows about this technology, or is willing to offer it, let alone one that has learned the skills required, and can fabricate it economically.

Dr. Arthur Jermyn, D.D.S., an implantologist and inventor, helped to solve this problem several years ago. He had developed a system and technique for the simplified production of suction cups onto a soft denture liner. Although it is simplified, it is not simple, at least not simple enough for most lab owners.

Dr. Jermyn had been marketing this system for over 20 years but gaining acceptance from labs had been slow. When I heard that both dentists and patients love it, and that there are over 20 years of testimonials with no negative contraindications, I became excited. I had studied suction cups in the past and knew the positive performance that they can provide the patient, if only they could be made economically. I started learning the technical skills required and now offer "Multi-Cup" denture service to my accounts.

Contraindications - Allergic Reactions

To date we have had no allergic reactions to the silicone liners. The only possible cause for deferment of denture construction is the presence of moniliasis in the mouth. If possible, this organism should first be eradicated, because the available silicone liners act as a propagating media for fungal growth.

The only physical tissue irritation encountered, has been caused by excessive suction cup height. These sore spots are easily treated, by trimming off part of the offending cup, using a modified nipper.

Technique

Before impressions are made, it is necessary to restore the optimum health to oral tissues.. Sometimes this may require the patient to go without his or her dentures for several days. Otherwise, it is necessary that the tissue be reconditioned by relining the old dentures using special tissue-conditioning resins. Directions for the application and use of these soft resin materials are available from their manufacturers.

New Dentures

The first step in making a new set of dentures is making an accurate set of impression trays. The handle on the tray should be centered directly over the anterior ridge, so that it does not interfere with the movement of the lips. The borders of the tray should be slightly under extended and rounded. Severe under extensions can be corrected by using tracking stick modeling, compounded to the tray, and manipulating the border tissues, producing a functionally accurate adaptation.

The final impression is made in a soft syringe type, rubber-based impression material, free of any voids or air bubbles.

Rebasing Old Dentures

Dentures may be rebased using the multiple suction cup technique, providing the dentures have the correct occlusion, centric relation, and occlusal dimensions. Before rebasing old dentures with this technique, sufficient space must exist under the teeth for both the new silicone liner and new acrylic resin. Also prior to rebasing old dentures, the dentist may have to cut away much of the under impression surface of the denture, and first treat the tissue with a tissue conditioning resin.

The borders should be corrected with tracking stick- modeling compound, making sure they are nicely rounded and accurate. The soft syringe type, rubber-based impression material is then used for making the final impression directly into the old denture.

Placement of Dentures

After the laboratory has precisely processed the denture, it is returned to the dentist. Prior to the insertion, the new dentures are soaked in the fungicide solution for at least 15 minutes and then rinsed with distilled water before being place in the patient's mouth. The patient is asked to maintain a closing pressure on the dentures for several minutes in order to allow the suction cups to flare out and partly settle into the tissue. The occlusion is then checked with articulating paper, to allow for the necessary occlusal adjustments. The patient is then dismissed, with a warning to eat a soft diet for the next few days, and to leave the dentures out during sleeping hours.

The patient is recalled within a week for further occlusal adjustments, and again a month later for final adjustments. During this time, any sore spots that occur due to excessive height of individual suction cups are easily located and relieved and should be trimmed with modified cuticle nippers.

Conclusion

A simple technique (for the dentist) for enhancing the retention and stability of dentures has been described. A large number of small suction cups formed from a soft, resilient silicone rubber are processed in an otherwise conventional denture. They grip the oral tissue without causing any pathosis returns. The tissue tends to temporarily assume the form of the cups, but then returns to normal when the dentures are removed. The tissue displays a pink, moist, and healthy normal appearance.

This technique solves many of the physiological and psychological problems associated with denture wearing, but this is no panacea for all denture troubles.

The procedure calls for working with a laboratory that is technologically advanced in the construction of this technique-sensitive procedure, but when properly done, the use of these multiple suction cups can make the difference between success and failure.

Because it is not much more expensive now, implementing Dr. Jermyn’s ” fabrication process”, it can (and should) be considered for all your denture patients. It can save your patient the cost and mess of denture adhesive creams and powders, and provides much better retention than adhesives.

In conclusion, these are exacting times in dentistry, with new developments and products being ushered into the millennium. We now have lighter, more comfortable, and aesthetic denture prosthesis, which are greatly needed. When considering that the 90's in dentistry proved somewhat frustrating and exciting, it is also evident that the turn of the century appears to hold many great solutions to previously unsolved problems.

For questions on fabricating this appliance, please call David Block at Aesthetic Porcelain Studios, Inc. (1-800-544-9605)