Initial Placement, Adjustment, and Servicing of the Removable Partial Denture:

Question 1

Goals of Delivery Appointment:

Answer 1

• Making the Insertion of the RPD COMFORTABLE by several adjustments
• Initial placement of the completed removable partial denture, should be a routinely scheduled appointment.
• Most of the times the prosthesis is quickly placed in the mouth, the patient is dismissed with instructions to return when soreness or discomfort develops.

Question 2

Patients should not be given possession of removable prostheses until:

Answer 2

1. Denture bases have been initially adjusted as required,
2. Occlusal discrepancies have been eliminated, and
3. Patient education procedures have been continued.

Question 3

Timing of Delivery appointment:

Answer 3

1. The delivery of the new prosthesis should be appointed early in the morning to have time for a double check after the patient has used the RPD for several hours.
2. This appointment should not be placed in the last day of the week. It is important to give the patient the chance for a second appointment the day after. Although the patient has no complaints with the denture or can remove the prosthesis for one day if any, patients mostly favor to see the dentist immediately

Question 4

Initial RPD Placement & Adjustments

Normally, some period of time is needed on behalf of the patient to adjust to his /her new dentures, however, some other factors must also be considered as well such as:

Answer 4

1. How well the patient has been informed of the mechanical and biological problems involved in the fabrication and wearing of a removable prosthetic restoration,
2. How much confidence the patient has acquired in the excellence of the finished product.

Question 5

The initial placement procedure which is considered to be the key to success for an acceptable prosthetic restoration includes the following steps:

Answer 5

1. adjustment of the bearing surfaces of the denture bases to be in harmony with the supporting soft tissue;
2. adjustment of the occlusion to accommodate the occlusal rests and other metal parts of the denture; and
3. final adjustment of the occlusion on the artificial dentition to harmonize with natural occlusion in all mandibular positions.

Question 6

1. Adjustments to bearing surfaces of denture bases:

Answer 6

• The ultimate fitting of the denture bearing surfaces is accomplished with the use of some kind of indicator paste.
• This procedure eliminates the possibility of pressure spots from causing sore tissues.
• The paste must be one that will be readily displaced by positive tissue contact and that will not adhere to the tissue of the mouth.
• Several pressure indicator pastes are commercially available.
• However, equal parts of a vegetable shortening and zinc oxide powder can be combined to make an acceptable paste.

Question 7

Initial RPD Placement & Adjustments:

The procedure:

Answer 7

• The patient cannot be expected to apply a heavy enough force to the new denture bases to register all of the pressure areas present. The dentist should apply both vertical and horizontal forces with the fingers in excess of what might be expected of the patient. The denture is then removed and inspected. Any areas where pressure has been heavy enough to displace a thin film of indicator paste should be relieved and the procedure repeated with a new film of indicator until excessive pressure areas have been eliminated.
• This procedure is particularly difficult to interpret when patients exhibit xerostomia. An area of the denture base that shows through the film of indicator paste may be erroneously interpreted as a pressure spot, when actually the paste had adhered to the tissue in that area. Therefore only those areas that show through an intact film of indicator paste should be interpreted as pressure areas and relieved accordingly.
• The decision to relieve an area of pressure must consider whether the pressure is in a primary, secondary, or non-supportive denture bearing area.
• The primary denture bearing areas should be expected to show greater contact than other areas.

Question 8

Initial RPD Placement & Adjustments

Pressure areas most commonly encountered are as follows:

Mandibular arch

Answer 8

Mandibular arch:

1. the lingual slope of the mandibular ridge in the premolar area,
2. the mylohyoid ridge,
3. the border extension into the retromylohyoid space, and
4. the distobuccal border in the vicinity of the ascending ramus and the external oblique ridge;

Question 9

Initial RPD Placement & Adjustments

Pressure areas most commonly encountered are as follows:

Maxillary arch:

Answer 9

Maxillary arch

1. the inside of the buccal flange of the denture over the tuberosities,
2. the border of the denture lying at the malar prominence, and
3. the point at the pterygomaxillary notch where the denture may impinge on the pterygomandibular raphe or the pterygoid hamulus.

Question 10

Q: How can you minimize the possible need for chairside adjustments at placement?

Answer 10

1. Ensure all previous treatment stages are completed correctly
2. Do not ‘carry over’ mistakes in the hope they can be corrected later on
3. Insist the RPD is delivered by the dental lab on a ‘modified’ cast

Question 11

Initial RPD Placement & Adjustments

Always Remember! – RPD Delivery:

Answer 11

• The working cast is destroyed when the RPD is finished in acrylic
• The dental lab must be instructed to duplicate the cast before finishing
• Soft tissue undercuts will have to be trimmed in the cast in order to
• seat the finished prosthesis unless previously blocked out
• In areas where the aim is to engage these undercuts, chairside adjustments may be needed
• All other areas, and any tooth undercuts should not require adjustments at placement

Question 12

Q: What other adjustments may be needed at placement of a RPD?

Adjustment of occlusion in harmony with natural and artificial dentition:

Answer 12

• The final step in the adjustment of the removable partial denture at the time of initial placement is the adjustment of the occlusion to harmonize with the natural occlusion in all mandibular excursions.
• When opposing removable partial dentures are placed concurrently, the adjustment of the occlusion will parallel to some extent the adjustment of occlusion on complete dentures.

Question 13

Q: How do you understand the Intraoral method?

Answer 13

• Occlusal adjustment of distal extension removable partial dentures is accomplished more accurately with the use of an articulator rather than by any intraoral method.
• Because distal extension denture bases will exhibit some movement under a closing force, intraoral indications of occlusal discrepancies, whether produced by articulating paper or disclosing waxes, are difficult to interpret. Distal extension dentures positioned on remounting casts can conveniently be related in the articulator with new, non-pressure interocclusal records, and the occlusion can be adjusted accurately at the appointment for initial placement of the dentures

Question 14

laboratory and clinical procedures performed for correction of occlusal discrepancies caused by processing of removable partial dentures.

Describe the cases:

Answer 14

A: In this case, the opposing arch is a complete denture that is not to be altered. To produce a cast for use in correcting the occlusion on the articulator, a pick-up impression of the mandibular prosthesis is made. The prosthesis stays within the irreversible hydrocolloid impression;

B: The remount cast that is formed is then inverted and positioned with the use of an interocclusal record.

Question 15

Intraoral occlusal adjustments

One of two methods may be used to locate specific areas to be relieved.

Answer 15

1. Articulation ribbon may be used to mark the occlusion; then those marks that represent areas of excessive contact are identified by referring to the wax record and are relieved accordingly.
2. A second method is to introduce the wax strips (Kerr corporation), this time adapting them to the buccal and lingual surfaces for retention. After the patient has tapped into the wax, perforated areas are marked with a waterproof pencil. The wax is then stripped off and the penciled areas are relieved.

Question 16

Instructions to the patients:

Answer 16

1. Before the patient is dismissed, he /she should be reminded of the chronic nature of the missing tooth condition and of the fact that treatment solutions, such as a removable partial denture (RPD), require monitoring to ensure that they continue to provide optimum function without harming the mouth.
2. REMEMBER! Correct use and maintenance of the RPD is risk management!
3. Patients should be instructed in the proper placement and removal of the removable partial denture. They should demonstrate that they can place and remove the prosthesis themselves. Clasp breakage can be avoided by instructing patients to remove the removable partial denture by the bases and not by repeated lifting of the clasp arms away from the teeth with the fingernails.
4. Patients should be advised that some discomfort or minor annoyance might be experienced initially. To some extent, this may be caused by the bulk of the prosthesis to which the tongue must become accustomed.

Question 17

Instructions to patients:

Phonetics:

Answer 17

Discussing phonetics with the patient in regard to the new dentures may indicate that some denture wearers have difficulty in pronouncing certain words clearly. They usually tend to lisp. This is caused by the fact that dentures change the shape of the mouth. Once the tongue, lips and cheeks are adjusted, speech returns to normal. With few exceptions, which usually result from excessive and preventable bulk in the denture design, contour of denture bases, or improper placement of teeth, the average patient will experience little difficulty in wearing the removable partial denture. Most hindrances to normal speech will disappear in a few days. A good tip would be to practice speaking in front of a mirror or by reading a newspaper aloud for a few minutes each day until they feel that they can speak clearly.

Question 18

Instructions to patients:

Gagging:

Answer 18

Similarly, perhaps little or nothing should be said to the patient about the possibility of gagging or the tongue’s reaction to a foreign object. Most patients will experience little or no difficulty in this regard, and the tongue will normally accept smooth, non-bulky contours without objection. If the design of the major connector was kept within in the limits and it was positioned correctly in the mouth then the tongue will normally adapt within a few days and the gag reflex will eventually diminish.

Question 19

Follow up services:

Answer 19

• The patient must understand the sixth and final phase of removable partial denture service (periodic recall) and its rationale. Patients need to understand that the support for a prosthesis (Kennedy Class I and II) may change with time. Patients may experience only limited success with the treatment and prostheses so meticulously accomplished by the dentist, unless they return for periodic oral evaluations.
• After all necessary adjustments have been made to the removable partial denture and the patient has been instructed on proper care of the denture, the patient must also be advised as to future care of the mouth to ensure health and longevity of the remaining structures.

Question 20

Rocking or loose denture:

Answer 20

The future development of denture rocking or looseness may be the result of a change in the form of the supporting ridges rather than lack of retention. This should be detected as early as possible after it occurs and corrected by relining or rebasing. The loss of tissue support is usually so gradual that the patient may be unable to detect the need for relining. This usually must be determined by the dentist at subsequent examinations as evidenced by rotation of the distal extension denture about the fulcrum line. If the removable partial denture is opposed by natural dentition, the loss of base support causes loss of occlusal contact, which may be detected by having the patient close on wax or Mylar strips placed bilaterally.