Clinical Applications of Appliance Therapy in General Dental Practice, Part 2 Temporary Partial Dentures

In part 1 of this series, the early treatment of anterior cross-bites in children was discussed, including examples of the type of interceptive orthodontics that simple appliance therapy can accomplish. In this article, the clinical applications of temporary partial dentures will be discussed.

Temporary removable partial dentures serve many useful purposes and are an integral part of any prosthodontic treatment plan.1 These appliances are classified according to the purpose for which they are used. The 3 types of temporary removable partial dentures are the interim, transitional, and treatment partial.1

INTERIM PARTIAL DENTURES

The interim partial denture is indicated when age, health, poor finances, or lack of time precludes a more definitive treatment. Some of the most common uses for an interim partial denture include the following:

(1) Space maintenance.

(2) Reestablishing occlusion.

(3) Replacing visible missing teeth while definitive restorative procedures are being accomplished.

(4) Application for the patient undergoing periodontal or other prolonged treatment.1

(5) Conditioning the patient to wear a removable prosthesis.

(6) Healing after an extraction or a traumatic injury.

(7) Maintenance of function while the patient is undergoing minor tooth movement (Figures 1 and 2).

Figure 1. To create an ideal arch form in this partially edentulous patient, the left bicuspid should be moved mesially and the anterior teeth moved labially. Figure 2. An Interim partial denture can be an effective tool to provide a patient with a functional occlusion while performing a minor tooth movement procedure.

Interim partial dentures are most often indicated in young patients who have experienced the loss of an anterior tooth or teeth. They may also be indicated for the young patient who has missing posterior teeth as a result of an accident, caries, or hereditary partial anodontia.2

Figure 3. Interim partial dentures are most often indicated in young patients who have experienced the loss of an anterior tooth.
Figure 4. Interim partial denture. Note that rest and clasp design do not interfere with normal occlusion.
Figure 5. Evaluate tooth size, shape, and color. Aesthetics are critical for patient acceptance.

Treatment usually consists of an interim partial denture or a series of dentures (if necessary) until facial skeletal growth is complete. Implants can be placed or the teeth adjacent to the space can be prepared for a fixed bridge. Often, the only other choice is to leave the edentulous spaces untreated, which can result in problems related to tooth migration and eruption2 (Figures 3 through 5).

Elderly patients whose health contraindicates lengthy and physically demanding appointments needed for fabrication of fixed bridges can be candidates for interim partial dentures. These patients can usually tolerate the simple clinical procedures needed to construct and insert an interim appliance.

Another indication for an interim partial denture may occur in patients with financial problems. The cost of this service is considerably less than for definitive treatment that will eventually be required.

TRANSITIONAL PARTIAL DENTURES

The transitional partial denture should be considered for a patient when extractions are contraindicated for physiological or psychological reasons.2 For example, this treatment plan can be used effectively with an elderly patient who ideally needs a denture but suffers from a chronic debilitating disease where multiple extractions could exacerbate the systemic illness. In a situation like this, maintaining the health of the remaining teeth is often less stressful.

Figure 6. With only a few remaining teeth, it may be necessary to transition a patient from partially to fully edentulous. Figure 7. A transitional partial denture should be carefully designed so the dentist can add teeth to the appliance.

Another example where a transitional partial denture may be potentially beneficial is for patients who are psychologically unable to accept the loss of their teeth. In the minds of many people, their smile is essential for sex appeal, youth, and happiness. If the patient is truly concerned about the loss of teeth, but the loss is inevitable, treatment should be carried out over as long a period as possible. For example, when a patient has extensive bone loss, even the most aggressive periodontal therapy may not be able to prevent the inevitable loss of teeth. It can, however, delay tooth loss. In a situation like this, a transitional partial denture is an ideal approach. Over time, the dentist will be able to replace teeth as  necessary3 (Figures 6 and 7).

           

TREATMENT PARTIAL DENTURES

The treatment partial denture may be used as a vehicle to treat or medicate the oral tissues, as a splint following surgical treatment in the oral cavity, and to assess tolerance of an increase or restoration of the vertical dimension of occlusion.2

TISSUE TREATMENT

An existing prosthesis can cause soft-tissue injury. This is especially true if poor oral hygiene is present. The soft tissues may respond in 1 of 2 ways: inflammatory hyperplasia or tissue recession. The most frequent responses are prolonged marginal gingivitis, possibly leading to chronic periodontitis; papillary hyperplasia; and the formation of an epulis fissuratum, which is a hyperplastic tissue response to an overextended border of a denture base.

Treatment of the affected area is best accomplished by replacing the offending appliance with a treatment partial denture that is designed to carry a tissue conditioning material such as Viscogel (Bentec). The mechanism of action is a combination of even distribution of forces, resulting in more intimate soft-tissue contact, and the mild tissue stimulation as the soft material compresses and relaxes during function. Through this action, blood flow through the affected tissues is increased, and the inflammatory response is reduced.2 A material such as Viscogel will need to be replaced every 4 to 5 days to be most effective.

SURGICAL SPLINTS

The healing of a surgical procedure in the oral cavity can be improved if the affected tissues are supported and/or protected by a temporary surgical splint. For example, using a surgical splint after reflection of a large portion of palatal tissue can reduce submucosal clot thickness and speed the postoperative course.2

Another surgical procedure that commonly lends itself to the support of a splint is the tissues on the lingual aspect of the mandibular ridge, a common place for bony exostosis. The lingual mucosa of the mandibular ridge is generally thin and friable. Protecting these tissues from the action of the tongue and from the effects of chewing can decrease postsurgical discomfort. In both examples, these protective splints can be lined with tissue-conditioning material to promote a more intimate adaptation of the reflected mucosa to the underlying bone.

Establishing Vertical Dimension

Figure 8. The loss of the posterior teeth can lead to a decrease in vertical dimension. Figure 9. Treatment partial dentures can be used to help reestablish the patient’s ideal vertical dimension.

When extensive dental reconstruction is to be undertaken, the desired vertical dimension of occlusion can be evaluated with a temporary prosthesis. As components of the total restoration are completed and cemented into place, segments can be eliminated from the treatment prosthesis4,5 (Figures 8 and 9). When the etiology of TMJ symptoms is believed to be a decreased vertical dimension of occlusion, occlusal rims and acrylic resin overlays can be attached to a partial denture to alter the level of the occlusion. The rims and overlays may be readily altered to increase or decrease the height of occlusion until clinical signs and subjective symptoms are eliminated.5

TREATMENT PROCEDURES

The first step in determining whether a temporary partial denture should be part of a treatment plan is to complete a thorough examination that includes discussing the treatment with the patient. It is at this step that the patient’s special needs (ie, financial, psychological, time constraints, etc) should be assessed. Once this has been accomplished, the following steps should be followed:

(1) Make sure that all aspects of care (restorations, periodontal therapy, etc) that are required prior to delivery of an acceptable temporary partial denture are completed before taking the impressions for construction of the appliance. It is important to consider the need for rest seats. When occlusal rests are incorporated, they provide sufficient resistance to vertical displacement of the prosthesis during function to protect the gingival tissue and alveolar bone from excessive force.

(2) Take accurate impressions of both dental arches, since an opposing cast will always be necessary for proper construction of the appliance. The impressions should be extended to capture all supporting tissues. In the mandibular impression, the anatomy of the ridge lingual to the natural teeth, and any missing teeth, must be captured. In the maxillary impression, the impression tray must be altered to eliminate any excessive space between the tray and the hard palate. If this is not accomplished, the impression material may sag, resulting in a poor fitting appliance.

(3) Pour the impressions immediately in a dense dental stone to prevent distortion of the master casts. This is especially important if the impressions were taken with an alginate or hydrocolloid material.

(4) Take an accurate occlusal record to allow for the proper articulation of the casts. This record must be an exact representation of the occlusal and vertical relationship that is desired. Overlooking this step will result in the need to spend an excessive amount of time at the delivery appointment adjusting the occlusion.

(5) Select a tooth shade by matching the remaining teeth to any standard shade guide. For example, a common plastic tooth shade guide is the Biotone guide. The laboratory can select the mold and size of the artificial teeth to be used by matching them to the remaining natural teeth on the master cast.

(6) Determine the type of retention that will be necessary. Although a significant amount of retention is gained both through the adaptation of the denture base to the soft tissue and engaging the interproximal undercuts, additional retention may be needed. When this is the case, retentive clasps may be used.

The most common clasps for temporary partial dentures are the ball clasp, C clasp, and the crozat clasp. All 3 are wroughtwire clasps made from orthodontic wire.6 When choosing a clasp, care should be taken not to interfere with the patient’s normal occlusion, since occlusal interferences will generally result in the patient not wearing the appliance.6

(7) Select the type of partial denture needed and prepare a detailed prescription for its fabrication. Include a description of how it is to be used. For example, indicating that the appliance will be used for tissue treatment will tell the laboratory to allow space to hold the tissue conditioning material. A completed laboratory instruction sheet should also include the following:

(a) The tooth shade.

(b) The type of retention desired.

(c) A description of how the teeth are to be set (abutted against the ridge, with or without a labial flange, overlapping of teeth, diastema, etc).

(d) The type of teeth to be used—plastic teeth are usually recommended since they can be easily adjusted and reshaped.

(e) An outline drawn of the denture base and its extensions, along with a written description.

(f) Whether a try-in appointment will be necessary.

(8) Attempt to achieve the best anterior aesthetics possible. In order to accomplish an aesthetic result, it may be necessary to have a try-in appointment. For example, if excess space exists in the natural dentition, creating a slight diastema is more natural than adding an extra tooth or using wider teeth. Where there is a lack of space, slight overlapping may be preferred. It is especially important to align the midline formed by the central incisors with the midline of the face, since any significant deviation will result in an unnatural appearance.

(9) On the day the appliance is delivered do the following:

(a) Check the tissue surface of the interim partial denture with pressure-indicating paste. This will identify any areas that may cause a problem with denture use. Carefully refine those areas. The goal is to achieve intimate contact between the denture base and the soft tissue without causing blanching or tissue irritation.

(b) Check the occlusion. The anterior teeth should be adjusted so only light contact is made in centric, lateral, and protrusive movements. The posterior occlusion is dependent upon the number of teeth that are present and the intended use of the appliance. For example, when only a few posterior teeth are being replaced, light occlusal contacts are indicated since the remaining dentition is usually sufficient to maintain function, and excessive contact on the partial denture may cause sore spots. On the other hand, when multiple posterior teeth are being replaced, a normal pattern of occlusal contacts is needed to provide the patient with a functional occlusion. When this is the case, it will be necessary to protect the underlying tissue by placing some rest seats. If this is not accomplished, rapid resorption of the underlying bone can occur.

(c) Adjust the clasps and make sure that the appliance is retentive.

Figure 10. This patient is undergoing extensive periodontal therapy. The lateral incisors and the first bicuspids have a guarded prognosis. Figure 11. Mandibular arch—lateral incisors, first and second bicuspids have a guarded prognosis.
Figure 12. The patient requests aesthetic temporary restorations. Figure 13. Mandibular transitional partial denture designed for addition of teeth.
Figure 14. Mandibular transitional partial denture restoring aesthetics and function. Figure 15. Maxillary transitional partial denture. If a decision is made to extract other teeth, replacement teeth can be added to the appliance.
Figure 16. Maxillary transitional partial denture designed to return function and aesthetics. Figure 17. The use of maxillary and mandibular transitional partial dentures allows the dentist to provide the patient with an aesthetic and functional occlusion in a cost-efficient manner.

The design of a transitional partial denture may require that teeth can be added to the original framework, preventing the necessity of remaking the partial denture because a single tooth or several teeth were subsequently lost. It is important to emphasize that patients treated with a transitional partial denture should be seen on a regular recall basis so the appliance and remaining teeth can be monitored (Figures 10 through 17).

The clinical procedures for fabricating a tissue treatment partial denture are basically the same as for the interim partial denture. The laboratory will leave space between the appliance and the tissue for the conditioning material. When seating a treatment partial denture, any plastic (the denture base) exposed through the material should be relieved and new conditioning material added. The best way to relieve the denture base is by coating the surface of the conditioning material with liquid soap, then cutting away the exposed plastic with acrylic burs. The liquid soap prevents the fragments of the denture base from attaching to the surface of the conditioning material. The soap and grindings are washed away, and additional conditioning material is added to the relieved areas.

Lastly, a temporary removable partial denture must never have a unilateral design. A unilateral partial denture presents a number of hazards, such as the patient swallowing or aspirating the appliance, and since the appliance will not distribute forces over a large enough area, further problems may occur to the teeth and soft tissues.4

PATIENTS WITH TEMPORARY PARTIAL DENTURES NEED SPECIAL CARE

Ideally, interim and transitional dentures should not be worn while sleeping. The mucosa requires time to heal without contact with a foreign body. Patients who insist on wearing their prosthesis while sleeping should be encouraged to leave the appliance out of the mouth for several hours during the day.

Generally, patients are more susceptible to caries when wearing a removable restoration. Adequate prophylactic measures must be taken, including fluoride treatments, to prevent decalcification and caries of the teeth that are in contact with the appliance. Patients must understand the importance of the care required of the temporary partial denture, the remaining teeth, and the soft tissues. The following instructions should be given to the patient:

(1) The partial denture, as well as the remaining natural teeth, will accumulate plaque, likely at a higher rate than normal. The use of plaque-disclosing tablets is an excellent way to demonstrate to the patient the areas that are susceptible to accumulation of plaque and debris.2

(2) While a cleaning agent can be used, the physical act of brushing is of primary importance. Toothpaste, facial soap, or any mild detergent can be used when cleaning the appliance, but avoid abrasive scouring powders. A regular toothbrush, a clasp brush, or a denture brush can be used to clean the appliance.

(3) When brushing the appliance, patients should be instructed to hold one side of the denture with their fingers while brushing the opposite side. Holding the denture in the palm could result in a break across the midline. It may also be advisable for some patients to brush their partial denture over a basin that is partially filled with water. If the basin is used and the appliance is dropped, it will not break.

CONCLUSION

This article has discussed the 3 types of temporary partial dentures—interim, transitional, and treatment—and their clinical indications and applications.


References

1. Henderson D. McCracken’s Removable Partial Prosthodontics. 6th ed. St Louis, Mo: CV Mosby Co; 1981:418-422.

2. Stewart K, Rudd K, Kuebker W. Clinical Partial Removable Prosthodontics. 2nd ed. Ishiyaku Euro-American Inc (Medical Dental Media Intl); 1992: Chapter 18.

3. Wagner G, Monesmith M. Transitional immediate complete dentures. Gen Dent. May-June 1991; 39:200-202.

4. Miller EL, Grasso JE. Removable Partial Prosthodontics. 2nd ed. Baltimore, MD: Williams & Wilkins; 1979:326-333.

5. Bade D, Lee T. Provisional reestablishment of occlusal vertical dimension. J Indiana Dental Assoc. 1990;69:23-26.

6. Reitz PV, Weiner MG. The fabrication of interim acrylic resin removable partial dentures with clasps. J Prosthetic Dent. 1978;

40:686-688.



Dr. Veis is a practicing dentist and a former associate clinical professor in restorative dentistry at the University of Southern California Dental School. He is known for his lectures on the integration of appliance therapy into the general practice, and is co-author of the text and home study course, “Principles of Appliance Therapy for Adults and Children.” A member of the American Dental Association, the Academy of General Dentistry, the Academy of Dental Sleep Medicine, the American Academy of Gnathologic Orthodontics, and the Academy of Sports Dentistry, Dr. Veis currently maintains a private practice in Los Angeles, Calif. He can be contacted at (800) 423-3270 or visit smldent.com.