The replacement of lost teeth in the anterior region of the dentition is a common request from patients. They are well motivated to persevere in the habituation of a denture that replaces anterior teeth in order to improve their appearance and may have quite modest demands for improved function. The aim of this case is to describe the assessment of a patient’s needs, plan appropriate treatment, and inform the patient of the risks and benefits of wearing a removable partial denture (RPD). It must be clear that the patient understands this before giving his or her consent to treatment. The clinical stages of making impressions, planning the RPD, assessing the trial denture, and placement of the finished denture will be described. In Appendix A, there is a review of the patient’s emotional response to the loss of his or her teeth, as it has important implications for patient management and attention to aesthetic requirements. The biological price of a partial denture describes the increased risk of dental caries and periodontal disease caused by the presence of an RPD in the oral cavity.
Removable partial dentures (RPDs) are not routinely successful. They may be loose, painful, appear unattractive when held in the hand, and at best, feel strange in the mouth until the wearer has become used to them. They require care from the dentist and the laboratory in fabricating them to be well adapted to the denture supporting tissues and to be aesthetically pleasing; they require perseverance from the patient in overcoming the natural resistance to having something foreign in the mouth and in learning to masticate with them. The patient’s reasons and motivation for having an RPD fabricated are important indicators of whether or not they will be successful.
These and other questions that you may think are useful should provide some insights into the patient’s attitudes to preserving their dentition and the motivation for wearing an RPD. The loss of anterior teeth has a profound impact on our body image. We need to understand the importance of teeth from a psychological viewpoint in order to empathize fully with a patient (see Appendix A.1 Psychology of tooth loss). If a relative is persuading the patient to have treatment, it may be necessary to advise the patient that unless he or she is well motivated, the treatment may not be successful.
At this stage, you should ask the patients, if you have not already done so, about their general health and record a medical history. Consult the procedure for obtaining a relevant medical history for determining the contraindications to dental treatment.
Ask the patient to close together on the back teeth (this should bring the teeth into maximum intercuspation), and make sure there is space available between the opposing teeth and the residual alveolar ridge to accommodate the base of an RPD. Less than 2 mm may be inadequate and require modification of the cusps of overerupted teeth.
Draw up a provisional treatment plan to restore carious teeth and to bring under control active periodontal disease. Plan to remove any teeth with a poor prognosis. There is a section at the end of this case guide that will review the modifications in procedure needed to provide immediate replacement of anterior teeth at the time of extraction.
You should have enough information to explain to the patients the options they have including the risks and benefits of RPDs (see Appendix A.3 Informed consent). An important issue will be retention of the RPD. The replacement of anterior missing teeth by means of acrylic resin–based RPD provides limited opportunities for active retention. The patient should understand that it may be necessary for him or her to use denture fixative to keep the denture in place. Even with fixative, any attempt to bite off pieces of food such as a cookie or apple may cause the denture to tip forward, rotating about the residual ridge.
A treatment option which should be considered and explained to the patients is a resin bonded or implant supported bridge (see Appendix A.7 Resin bonded bridge).
The preservation of the remaining teeth is a priority both to ensure that there is no further tooth loss and that the partial denture does not become redundant in a few years’ time due to further tooth loss. The patient should know that a partial denture increases the levels of plaque even in the presence of good oral hygiene. The risks of dental caries and periodontal disease are increased (see Appendix A.2 The biological price of partial dentures). The patient will need advice on improving plaque control, as every RPD increases the levels of plaque on adjacent teeth. The patient may benefit from prophylactic sessions with an oral hygienist.
When your patient has been well informed and understands what could be achieved with an RPD, and has concluded that the effort and money he or she will be spending is worthwhile, it is time to begin the preparatory restorative work and periodontal treatment.
When preparatory work is underway to control active caries and periodontal disease, you may find it worthwhile to make preliminary impressions so as to be able to study diagnostic casts of the patient’s dentition. Select stock impression trays (dentate) of a suitable size by first trying the average-sized tray in the mouth without material. Apply the technique described for inserting the tray into the mouth as described for the mandibular tray in ▶Fig. 1.1 and the maxillary tray in ▶Fig. 1.2. The tray is suitable if it covers and surrounds the arch of teeth and is not so large as to be difficult to insert.
Fig. 1.1 Trials insertion of a mandibular stock impression tray. (a) Stand facing the patient with the chair in an upright position. Hold the tray, facing downward between the first two fingers and the thumb of the right hand. (b) Rotate the tray slightly anticlockwise and then use the right extension of the tray to gently retract the left corner of the patient’s mouth. (c) Use your left forefinger to retract the right corner of the mouth. (d) Now rotate the tray clockwise into the mouth above the tongue. (e) Keep retracting with the left forefinger so that you can see the dental arch while you seat the tray over the teeth. Try to keep the tray handle facing straight forward so that the tray is symmetrically seated over the dental arch. Firmly seat the tray over the teeth. (f) Now ask the patient first to pout the lips over the borders of the tray and then to push the tongue forward.
Fig. 1.2 Trials insertion of a maxillary stock impression tray. (a) Stand behind the patient with the chair upright and in its lowest position. You should be able to rest your right forearm lightly on the patient’s right shoulder. This will give some control to your right hand as you approach the mouth. Hold the tray facing upward between the first two fingers and the thumb of the right hand. (b) Rotate the tray slightly clockwise and then use the right extension of the tray to gently retract the right corner of the patient’s mouth. (c) Use your left forefinger to retract the left corner of the mouth. Now rotate the tray anticlockwise into the mouth. (d) As the tray passes the lips, slide the left finger toward the midline, and now use your thumb to hold the maxillary lip and retract it gently forward so that you can see the anterior teeth. Keep retracting as you seat the tray over the maxillary arch. Try to keep the tray handle facing straight forward so that the tray is symmetrically seated over the dental arch. (e) Now ask the patient first to pout the lips and then to move the jaw from side to side. Ask the patient to breathe deeply and slowly if he or she feels nauseous. (f) To remove the tray, slide your left finger backward along the tray border and use the nail side of your finger to ease the back of the tray downward away from the teeth.