The objectives to be achieved during insertion of the prosthesis are the following:
• Refine intra-arch control
• Refine interarch control
• Deliver patient instructions Errors associated with the definitive prosthesis can be derived from the following:
• Tissues not completely recovered from irritation or displace- ment from a poorly fitting prosthesis when final impressions were made
• Errors associated with the surface detail of the impression
• Changes or damage to the master cast
• Poorly adapted record bases when the maxillomandibular records were made
• Distortion of or dimensional changes associated with regis- tration materials while making the record or mounting the record on an articulator
• Inaccurate maxillomandibular relation records
• Changes in the patient’s temporomandibular joint
• Articulator mounting errors
• Dimensional errors secondary to flasking and processing
The potential for error during fabrication of the removable partial denture (RPD) requires that all steps be accepted as ten- tative until the definitive prosthesis is available for the final and most accurate fitting. This in no way suggests that all procedures up to the insertion steps should be less than as ideal as possible but that there should be a series of ongoing checks, evaluations, and corrective measures available to reduce the potential for introducing error into the finished prosthesis.
Intra-arch Control
The objective of these procedures is to refine the tissue adapta- tion of the prosthesis. This refines the support derived from the remaining dentition and mucosa. The impression and fabrica- tion procedures are subject to technical and procedural errors. Errors can be made during the making of impressions and casts, maxillomandibular registrations, or processing of the definitive prosthesis. Clinical procedures performed during delivery can also accommodate for minor soft tissue changes that may have occurred since the final impression was made. With the finished prosthesis, these discrepancies can be identified and corrected to provide the best possible adaptation and support for the definitive prosthesis.
Tissue surface refinement
Before the delivery appointment, a thorough visual and digital examination is made of the finished prosthesis for spicules, rough or sharp areas, or processing irregularities. The delivery appointment begins by explaining the insertion procedures to the patient.
Pressure indicating paste (PIP) is used to identify areas of excessive tissue displacement (Fig 19-1). PIP is applied to the tissue surfaces of the prosthesis with a PIP brush. The prosthesis is inserted intraorally, seated with finger pressure, then removed and examined for pressure areas where the paste is displaced or for lack of appropriate adaptation as demonstrated by little or no compression of the PIP brush pattern. The pressure areas are relieved with an acrylic bur, and the PIP process is repeated until there is evidence of even flattening of the PIP brush pattern.
Refinement of the peripheral extensions
Disclosing wax is used to identify areas of overextension (Fig 19-2). The wax is adapted to the extensions, and the prosthesis is inserted. The patient is instructed to move the mandible and tongue, then manipulate the lips and cheeks. The prosthesis is removed. Areas observed where the wax has been displaced indicate areas of overextension. These areas are carefully ad- justed. This process is repeated until the areas of overextension are eliminated. These procedures ensure that the adaptation of the denture to the tissue surfaces and the peripheral extensions will be idealized.
Interarch Control
Interarch control is determined by the occlusal surface contacts between the maxillary and mandibular dentition. Adjustment and refinement of these surfaces must be coordinated and com- patible with the anatomy and mandibular movements of each individual patient at the time the prosthesis is inserted. This pro- cess is primarily used when an RPD opposes a complete denture. The most positive and precise method of refining interarch occlusion is to transfer a record of the occlusal surfaces of each arch to the laboratory, where final adjustments can be accom- plished. In the partially edentulous patient, this procedure requires that the finished prosthesis and a replica of the occlusal surfaces of the remaining teeth be transferred to the articulator. These teeth must retain their position in relation to the pros- thesis as established at the final fitting of the finished denture to the individual arch.
The clinical remount and equilibration is accomplished as follows:
1. A centric relation (CR) record can be obtained at this point or after the remount casts are made. If the record is made at this point, it should be made with a material that permits easy retrieval and storage of the record. If the RPD opposes a maxillary prosthesis with complete palatal coverage with a post dam, the prosthesis must be fully seated prior to making the record. This is accomplished by inserting both prostheses and instructing the patient to occlude on cotton rolls placed in the premolar area bilaterally for 5 minutes before making the record (Fig 19-3).
2. With the prosthesis secured in position, an alginate impres- sion (occlusal surfaces only) is made of the prosthesis and the remaining dentition.
3. The so-called “pickup impression” is removed with the pros- thesis embedded with the impression (Fig 19-4a).
4. Undercuts associated with the denture base, retainers, and RPD casting are blocked out (Fig 19-4b). Undercuts associ- ated with the extension base are blocked out with wet pumice or another suitable material.
5. Fast-setting dental stone or low-fusing metal is poured into the impression to reproduce the natural teeth (Fig 19-4c).
The prosthesis and the stone or metal occlusal surfaces are removed from the impression. Low-fusing metal (Fig 19-5) is favored by many clinicians because it solidifies quickly and produces a hard remount cast that is resistant to abrasion and chipping
This procedure reproduces the occlusal surfaces of the entire arch, including the prosthesis itself, with the natural teeth in stone or metal. This creates a quick, effective, and durable re- production of the relationship developed at the fitting of the prosthesis.
When the arch has been restored with an RPD, the plaster mounting should engage only the peripheral extensions of the prosthesis and the base surface of the replica of the residual dentition. Such a mounting will permit easy removal and re- placement of the prosthesis into an exact keyed position (see Figs 19-4 and 19-5).
Facebow record
If the RPD is opposed by a complete denture, a facebow trans- fer remount jig may be requested and produced by the dental laboratory at the time of the processing procedure (Fig 19-6). If a facebow transfer jig is not available, a new facebow record is obtained. The maxillary prosthesis and remount cast are then remounted on the articulator using this record.
Maxillomandibular record
If not made earlier, the final maxillomandibular registrations are made and transferred to the articulator, and the mandibular cast is mounted. The authors prefer to verify the record with a second set of records. The following precautions are taken in order to ensure the making of accurate records:
• The patient must not touch the denture teeth together or exert pressure on the denture base while making the record. Premature occlusal contacts can trigger tissue displacement or alter the mandibular closure pattern of the patient.
• As mentioned previously, if the RPD opposes a maxillary prosthesis with complete palatal coverage with a post dam, the prosthesis must be fully seated prior to making the record (see Fig 19-3). A maxillomandibular record, if not made previously, is made with the material of choice (Fig 19-7). The authors prefer dental compound (Fig 19-8).
• The stone or low-fusing metal replica of the residual dentition is secured to the prosthesis with sticky wax and mounted on the articulator with the record.
• A second record is made and secured to the mounted casts/ prosthesis, and then the accuracy of the first articulator mounting is confirmed. If the two records do not coincide, the mounting procedure is repeated until two compatible records are obtained.
A variety of materials have been used for making interocclusal records, including modeling plastic (dental compound), plaster, wax, bite registration paste, and silicone registration materials. A registration material that sets to a hard, unchanging form is favored. The material should have minimal resistance to closure and have a quick setting time. Dental compound is ideally suited for this purpose (see Fig 19-8). The material can be quickly and uniformly softened in a water bath and securely adapted to the occlusal surfaces of the prosthesis. The compound hardens quickly, is easily trimmed so that only shallow cusp indentations remain, cannot be distorted when hardened, and can quickly be resoftened in the water bath to remake the record
Protrusive record
A protrusive record is made with the mandible positioned 4 to 6 mm forward of the CR position. Dental compound is favored when making these records (see Fig 19-8). The record is then transferred to the mounted casts/prosthesis apparatus, the inclination of the condyles is determined, and the articulator is adjusted accordingly.
Occlusal refinement and equilibration
The rationale for completing a clinical remount and occlusal equilibration is to obtain a definite, repeatable, and proven relationship between the maxillary and mandibular arches prior to final adjustments of the opposing occlusal surfaces. The occlu- sion developed for the definitive prosthesis affects the freedom of mandibular movement and influences the forces delivered to the teeth and the edentulous bearing surfaces. Adjustments with the cast and prosthesis mounted on an articulator with accurate and reproducible records are easily accomplished, the movements of the articulator are repeatable and precise, and refinement of the occlusion can be accomplished quickly and precisely. Occlusal adjustments made intraorally are more dif- ficult to accomplish precisely, especially when equilibrating extension-base RPDs (Fig 19-9).
Basic rules for equilibration
• Adjust for CR first. The maxillary lingual cusp tips of the pos- terior teeth must contact the central fossa of the mandibular teeth. Contour the fossa to achieve positive centric contacts.
• Adjust the mandibular tooth surfaces to permit smooth, unencumbered, eccentric movements in all excursions per the occlusal scheme. When an extension-base RPD opposes a complete denture, balanced articulation is employed. When the anterior natural dentition in both arches has been retained and the RPD restores the extension areas, anterior guidance is advised, with the edentulous extension areas restored with centric-only contact.
Natural teeth opposing denture teeth
• Make adjustments on the denture teeth opposing the natural teeth.
• When it is necessary to alter the natural teeth, perform the needed alterations on the cast, mark these areas on the cast, and reproduce these alterations intraorally.
Finish and polish
• Check for smooth, unimpeded movement of opposing oc- clusal surfaces during eccentric movements. Eliminate rough or bumpy movements.
• Inspect and smooth all surfaces; restore anatomy as much as possible.
• Lightly polish the denture teeth.
• Smooth, round, and polish all metal edges.
• Highly polish the peripheral extensions.
Figure 19-10 shows the completed prostheses.
Intraoral evaluation
The adjusted and polished prosthesis is inserted intraorally, and the following checks are made:
• Verify simultaneous, even contact of the denture teeth and natural dentition.
• Confirm the planned anterior guidance of the natural denti- tion during excursions. Ensure that there are no interferences of the occlusal surfaces of the posterior teeth during lateral and protrusive movements.
• When an RPD opposes a complete denture, verify that the occlusal scheme is balanced articulation.
• Ask the patient if there are pressure areas or sharp edges that may irritate the tongue, cheeks, or lips. Make adjustments as necessary.
When to instruct patients in dental care
Patients are instructed, educated, and conditioned during the entire period of treatment. Note that little of what the clinician says will be retained if the instructions are given while treating the patient and performing a specific task (eg, making im- pressions and records). The patient is more interested in what the clinician is doing than in listening to instructions. This is especially true when a prosthesis or other material has just been placed in the mouth.
Why patient instruction is necessary
Younger patients are not always willing to accept an artificial replacement as readily as more mature individuals, and this is especially true of removable prostheses. If irritation develops on the denture-bearing tissues or surfaces of the tongue, patients are likely to remove the partial denture, place it in a drawer, and not remember it until much later when they become “dentally conscious” again, usually because of dental pain or discomfort. Patients have no way of knowing how to care for their RPDs. It is your responsibility as the clinician to instruct them as part of their treatment.
Instructions for RPD insertion and maintenance
Placement of the prosthesis
Insert and seat the RPD using the fingers. Never instruct the patient to “bite” the prosthesis into place. This action could bend or break the prosthesis or cause harm to the remaining teeth. RPDs have a definitive path of insertion. Make sure that the patient practices placement and removal of the prosthesis in front of a mirror. If the prosthesis seems to bend or does not slide smoothly into place, check the direction of insertion.
Removal of the prosthesis
Instruct the patient to remove the prosthesis at night and store it in water. To avoid bending the prosthesis or damaging the dentition, instruct the patient to remove the prosthesis along the same path used during insertion.
Cleaning the prosthesis
• Clean the prosthesis and the natural dentition after every meal or snack (Fig 19-11).
• Keep a brush at work as well as at home.
• Use care when cleaning the prosthesis. Avoid dropping the prosthesis and scrub it over a basin filled with water or a towel.
• Hold the prosthesis carefully and avoid squeezing and bending flexible parts such as the retainers.
• Effervescent denture cleansers specifically designed for use for RPDs can be used to supplement hygiene.
Denture compatibility
It will be several days or weeks before the prosthesis no longer feels like a foreign object to the patient. Also, advise the pa- tient not to expect an immediate improvement in mastication efficiency. It takes time and practice for the tongue, cheeks, and lips to accommodate to the contours of the prosthesis and manipulate the food bolus in concert with the prosthesis. Early phonetic difficulties are best resolved by instructing the patient to read aloud or practice words that are especially troublesome.
Follow-up examinations
The patient is given an appointment 24 hours post-insertion. Areas causing irritation or discomfort should be relieved immedi- ately. PIP is used to identify pressure areas on the denture-bearing surfaces, and disclosing wax is used to identify sections of the denture flanges that are overextended. If further difficulties are anticipated, the patient is given an appointment the following day. Otherwise, the next follow-up appointment should be scheduled 1 week later. This will ensure that the patient will transition smoothly through the accommodation stage with minimum difficulty.
Stannous fluoride gel is prescribed for daily application to all parts of the prosthesis that are in contact with tooth surfaces. The gel is applied in a thin layer with a cotton tip applicator after the prosthesis and the dentition have been thoroughly cleaned. Periodic follow-up examinations are mandatory. The patient should be impressed with the necessity for regular 6-month follow-up examinations. It is incumbent upon the dental practitioner to establish an efficient recall system for his or her patients.
Written instructions for the patient
Figure 19-12 lists written instructions that are given to patients to take with them.
Relines
Examination and evaluation of the RPD patient is scheduled every 6 months. Determining if there are tissue and bone changes of the edentulous support area under the extension portion of the prosthesis is a primary concern. Proper evaluation requires removal of the prosthesis for a 24-hour period prior to exam- ination of the support tissues so they can return to their natural contours. The adaptation of the prosthesis to the mucosa can then be checked for even contact with PIP, and the alveolar ridge can be observed for possible changes or resorption.
Further evaluation of changes in the ridge support are made by observing the amount of movement that occurs when force is applied in the extension portion of the prosthesis. Excessive denture movement is evidenced by lifting the indirect retainer rests off their rest seats.
Another method of evaluating changes requiring relining is the use of articulating ribbon or celluloid strips between the occlusal surfaces. If there has been bone resorption or ridge support changes, the occlusal surfaces will not record or hold the strips when the patient is in a closed position.
Reline procedure
The reline procedure is basically the same as an altered cast impression:
1. Instruct the patient to remove the prosthesis for 24 hours prior to the reline appointment or until the edentulous areas are healthy.
2. Remove sufficient acrylic resin from the tissue surface of the denture base to allow at least 1 mm of space between the denture base and the tissue.
3. Mold the periphery with tempered dental compound.
4. Remove all dental compound that has flowed onto the tissue side of the denture base.
5. Make a final closed-mouth impression with a suitable im- pression material.
6. Flask the RPD and process with acrylic resin.
7. Insert the RPD following the same procedure employed during delivery of the new prosthesis. Post-insertion instructions and follow-up appointments are identical to those described for a new prosthesis
• Refine intra-arch control
• Refine interarch control
• Deliver patient instructions Errors associated with the definitive prosthesis can be derived from the following:
• Tissues not completely recovered from irritation or displace- ment from a poorly fitting prosthesis when final impressions were made
• Errors associated with the surface detail of the impression
• Changes or damage to the master cast
• Poorly adapted record bases when the maxillomandibular records were made
• Distortion of or dimensional changes associated with regis- tration materials while making the record or mounting the record on an articulator
• Inaccurate maxillomandibular relation records
• Changes in the patient’s temporomandibular joint
• Articulator mounting errors
• Dimensional errors secondary to flasking and processing
The potential for error during fabrication of the removable partial denture (RPD) requires that all steps be accepted as ten- tative until the definitive prosthesis is available for the final and most accurate fitting. This in no way suggests that all procedures up to the insertion steps should be less than as ideal as possible but that there should be a series of ongoing checks, evaluations, and corrective measures available to reduce the potential for introducing error into the finished prosthesis.
Intra-arch Control
The objective of these procedures is to refine the tissue adapta- tion of the prosthesis. This refines the support derived from the remaining dentition and mucosa. The impression and fabrica- tion procedures are subject to technical and procedural errors. Errors can be made during the making of impressions and casts, maxillomandibular registrations, or processing of the definitive prosthesis. Clinical procedures performed during delivery can also accommodate for minor soft tissue changes that may have occurred since the final impression was made. With the finished prosthesis, these discrepancies can be identified and corrected to provide the best possible adaptation and support for the definitive prosthesis.
Tissue surface refinement
Before the delivery appointment, a thorough visual and digital examination is made of the finished prosthesis for spicules, rough or sharp areas, or processing irregularities. The delivery appointment begins by explaining the insertion procedures to the patient.
Refinement of the peripheral extensions
Disclosing wax is used to identify areas of overextension (Fig 19-2). The wax is adapted to the extensions, and the prosthesis is inserted. The patient is instructed to move the mandible and tongue, then manipulate the lips and cheeks. The prosthesis is removed. Areas observed where the wax has been displaced indicate areas of overextension. These areas are carefully ad- justed. This process is repeated until the areas of overextension are eliminated. These procedures ensure that the adaptation of the denture to the tissue surfaces and the peripheral extensions will be idealized.
Interarch Control
Interarch control is determined by the occlusal surface contacts between the maxillary and mandibular dentition. Adjustment and refinement of these surfaces must be coordinated and com- patible with the anatomy and mandibular movements of each individual patient at the time the prosthesis is inserted. This pro- cess is primarily used when an RPD opposes a complete denture. The most positive and precise method of refining interarch occlusion is to transfer a record of the occlusal surfaces of each arch to the laboratory, where final adjustments can be accom- plished. In the partially edentulous patient, this procedure requires that the finished prosthesis and a replica of the occlusal surfaces of the remaining teeth be transferred to the articulator. These teeth must retain their position in relation to the pros- thesis as established at the final fitting of the finished denture to the individual arch.
The clinical remount and equilibration is accomplished as follows:
1. A centric relation (CR) record can be obtained at this point or after the remount casts are made. If the record is made at this point, it should be made with a material that permits easy retrieval and storage of the record. If the RPD opposes a maxillary prosthesis with complete palatal coverage with a post dam, the prosthesis must be fully seated prior to making the record. This is accomplished by inserting both prostheses and instructing the patient to occlude on cotton rolls placed in the premolar area bilaterally for 5 minutes before making the record (Fig 19-3).
2. With the prosthesis secured in position, an alginate impres- sion (occlusal surfaces only) is made of the prosthesis and the remaining dentition.
3. The so-called “pickup impression” is removed with the pros- thesis embedded with the impression (Fig 19-4a).
4. Undercuts associated with the denture base, retainers, and RPD casting are blocked out (Fig 19-4b). Undercuts associ- ated with the extension base are blocked out with wet pumice or another suitable material.
5. Fast-setting dental stone or low-fusing metal is poured into the impression to reproduce the natural teeth (Fig 19-4c).
The prosthesis and the stone or metal occlusal surfaces are removed from the impression. Low-fusing metal (Fig 19-5) is favored by many clinicians because it solidifies quickly and produces a hard remount cast that is resistant to abrasion and chipping
This procedure reproduces the occlusal surfaces of the entire arch, including the prosthesis itself, with the natural teeth in stone or metal. This creates a quick, effective, and durable re- production of the relationship developed at the fitting of the prosthesis.
When the arch has been restored with an RPD, the plaster mounting should engage only the peripheral extensions of the prosthesis and the base surface of the replica of the residual dentition. Such a mounting will permit easy removal and re- placement of the prosthesis into an exact keyed position (see Figs 19-4 and 19-5).
Facebow record
If the RPD is opposed by a complete denture, a facebow trans- fer remount jig may be requested and produced by the dental laboratory at the time of the processing procedure (Fig 19-6). If a facebow transfer jig is not available, a new facebow record is obtained. The maxillary prosthesis and remount cast are then remounted on the articulator using this record.
Maxillomandibular record
If not made earlier, the final maxillomandibular registrations are made and transferred to the articulator, and the mandibular cast is mounted. The authors prefer to verify the record with a second set of records. The following precautions are taken in order to ensure the making of accurate records:
• The patient must not touch the denture teeth together or exert pressure on the denture base while making the record. Premature occlusal contacts can trigger tissue displacement or alter the mandibular closure pattern of the patient.
• As mentioned previously, if the RPD opposes a maxillary prosthesis with complete palatal coverage with a post dam, the prosthesis must be fully seated prior to making the record (see Fig 19-3). A maxillomandibular record, if not made previously, is made with the material of choice (Fig 19-7). The authors prefer dental compound (Fig 19-8).
• The stone or low-fusing metal replica of the residual dentition is secured to the prosthesis with sticky wax and mounted on the articulator with the record.
• A second record is made and secured to the mounted casts/ prosthesis, and then the accuracy of the first articulator mounting is confirmed. If the two records do not coincide, the mounting procedure is repeated until two compatible records are obtained.
A variety of materials have been used for making interocclusal records, including modeling plastic (dental compound), plaster, wax, bite registration paste, and silicone registration materials. A registration material that sets to a hard, unchanging form is favored. The material should have minimal resistance to closure and have a quick setting time. Dental compound is ideally suited for this purpose (see Fig 19-8). The material can be quickly and uniformly softened in a water bath and securely adapted to the occlusal surfaces of the prosthesis. The compound hardens quickly, is easily trimmed so that only shallow cusp indentations remain, cannot be distorted when hardened, and can quickly be resoftened in the water bath to remake the record
Protrusive record
A protrusive record is made with the mandible positioned 4 to 6 mm forward of the CR position. Dental compound is favored when making these records (see Fig 19-8). The record is then transferred to the mounted casts/prosthesis apparatus, the inclination of the condyles is determined, and the articulator is adjusted accordingly.
Occlusal refinement and equilibration
The rationale for completing a clinical remount and occlusal equilibration is to obtain a definite, repeatable, and proven relationship between the maxillary and mandibular arches prior to final adjustments of the opposing occlusal surfaces. The occlu- sion developed for the definitive prosthesis affects the freedom of mandibular movement and influences the forces delivered to the teeth and the edentulous bearing surfaces. Adjustments with the cast and prosthesis mounted on an articulator with accurate and reproducible records are easily accomplished, the movements of the articulator are repeatable and precise, and refinement of the occlusion can be accomplished quickly and precisely. Occlusal adjustments made intraorally are more dif- ficult to accomplish precisely, especially when equilibrating extension-base RPDs (Fig 19-9).
Basic rules for equilibration
• Adjust for CR first. The maxillary lingual cusp tips of the pos- terior teeth must contact the central fossa of the mandibular teeth. Contour the fossa to achieve positive centric contacts.
• Adjust the mandibular tooth surfaces to permit smooth, unencumbered, eccentric movements in all excursions per the occlusal scheme. When an extension-base RPD opposes a complete denture, balanced articulation is employed. When the anterior natural dentition in both arches has been retained and the RPD restores the extension areas, anterior guidance is advised, with the edentulous extension areas restored with centric-only contact.
Natural teeth opposing denture teeth
• Make adjustments on the denture teeth opposing the natural teeth.
• When it is necessary to alter the natural teeth, perform the needed alterations on the cast, mark these areas on the cast, and reproduce these alterations intraorally.
Finish and polish
• Check for smooth, unimpeded movement of opposing oc- clusal surfaces during eccentric movements. Eliminate rough or bumpy movements.
• Inspect and smooth all surfaces; restore anatomy as much as possible.
• Lightly polish the denture teeth.
• Smooth, round, and polish all metal edges.
• Highly polish the peripheral extensions.
Figure 19-10 shows the completed prostheses.
Intraoral evaluation
The adjusted and polished prosthesis is inserted intraorally, and the following checks are made:
• Verify simultaneous, even contact of the denture teeth and natural dentition.
• Confirm the planned anterior guidance of the natural denti- tion during excursions. Ensure that there are no interferences of the occlusal surfaces of the posterior teeth during lateral and protrusive movements.
• When an RPD opposes a complete denture, verify that the occlusal scheme is balanced articulation.
• Ask the patient if there are pressure areas or sharp edges that may irritate the tongue, cheeks, or lips. Make adjustments as necessary.
Maintenance and Patient Instructions
Patient preparation and instruction are continuing, ongoing communications that are part of every appointment and pro- cedure. However, the patient will retain more information for a longer period if it is written and repeated several times. It is important that patients be informed and conditioned as to what to expect with the use of RPDs, such as feelings of fullness or of a foreign object in the mouth. The importance of maintaining cleanliness of remaining teeth, tissues, and the prosthesis must be emphasized repeatedly. Explicit instructions for maintenance are essential. Patient education cannot be effectively performed during a single appointment; it is an ongoing challengeWhen to instruct patients in dental care
Patients are instructed, educated, and conditioned during the entire period of treatment. Note that little of what the clinician says will be retained if the instructions are given while treating the patient and performing a specific task (eg, making im- pressions and records). The patient is more interested in what the clinician is doing than in listening to instructions. This is especially true when a prosthesis or other material has just been placed in the mouth.
Why patient instruction is necessary
Younger patients are not always willing to accept an artificial replacement as readily as more mature individuals, and this is especially true of removable prostheses. If irritation develops on the denture-bearing tissues or surfaces of the tongue, patients are likely to remove the partial denture, place it in a drawer, and not remember it until much later when they become “dentally conscious” again, usually because of dental pain or discomfort. Patients have no way of knowing how to care for their RPDs. It is your responsibility as the clinician to instruct them as part of their treatment.
Instructions for RPD insertion and maintenance
Placement of the prosthesis
Insert and seat the RPD using the fingers. Never instruct the patient to “bite” the prosthesis into place. This action could bend or break the prosthesis or cause harm to the remaining teeth. RPDs have a definitive path of insertion. Make sure that the patient practices placement and removal of the prosthesis in front of a mirror. If the prosthesis seems to bend or does not slide smoothly into place, check the direction of insertion.
Removal of the prosthesis
Instruct the patient to remove the prosthesis at night and store it in water. To avoid bending the prosthesis or damaging the dentition, instruct the patient to remove the prosthesis along the same path used during insertion.
Cleaning the prosthesis
• Clean the prosthesis and the natural dentition after every meal or snack (Fig 19-11).
• Keep a brush at work as well as at home.
• Use care when cleaning the prosthesis. Avoid dropping the prosthesis and scrub it over a basin filled with water or a towel.
• Hold the prosthesis carefully and avoid squeezing and bending flexible parts such as the retainers.
• Effervescent denture cleansers specifically designed for use for RPDs can be used to supplement hygiene.
Denture compatibility
It will be several days or weeks before the prosthesis no longer feels like a foreign object to the patient. Also, advise the pa- tient not to expect an immediate improvement in mastication efficiency. It takes time and practice for the tongue, cheeks, and lips to accommodate to the contours of the prosthesis and manipulate the food bolus in concert with the prosthesis. Early phonetic difficulties are best resolved by instructing the patient to read aloud or practice words that are especially troublesome.
Follow-up examinations
The patient is given an appointment 24 hours post-insertion. Areas causing irritation or discomfort should be relieved immedi- ately. PIP is used to identify pressure areas on the denture-bearing surfaces, and disclosing wax is used to identify sections of the denture flanges that are overextended. If further difficulties are anticipated, the patient is given an appointment the following day. Otherwise, the next follow-up appointment should be scheduled 1 week later. This will ensure that the patient will transition smoothly through the accommodation stage with minimum difficulty.
Stannous fluoride gel is prescribed for daily application to all parts of the prosthesis that are in contact with tooth surfaces. The gel is applied in a thin layer with a cotton tip applicator after the prosthesis and the dentition have been thoroughly cleaned. Periodic follow-up examinations are mandatory. The patient should be impressed with the necessity for regular 6-month follow-up examinations. It is incumbent upon the dental practitioner to establish an efficient recall system for his or her patients.
Written instructions for the patient
Figure 19-12 lists written instructions that are given to patients to take with them.
Relines
Examination and evaluation of the RPD patient is scheduled every 6 months. Determining if there are tissue and bone changes of the edentulous support area under the extension portion of the prosthesis is a primary concern. Proper evaluation requires removal of the prosthesis for a 24-hour period prior to exam- ination of the support tissues so they can return to their natural contours. The adaptation of the prosthesis to the mucosa can then be checked for even contact with PIP, and the alveolar ridge can be observed for possible changes or resorption.
Further evaluation of changes in the ridge support are made by observing the amount of movement that occurs when force is applied in the extension portion of the prosthesis. Excessive denture movement is evidenced by lifting the indirect retainer rests off their rest seats.
Another method of evaluating changes requiring relining is the use of articulating ribbon or celluloid strips between the occlusal surfaces. If there has been bone resorption or ridge support changes, the occlusal surfaces will not record or hold the strips when the patient is in a closed position.
Reline procedure
The reline procedure is basically the same as an altered cast impression:
1. Instruct the patient to remove the prosthesis for 24 hours prior to the reline appointment or until the edentulous areas are healthy.
2. Remove sufficient acrylic resin from the tissue surface of the denture base to allow at least 1 mm of space between the denture base and the tissue.
3. Mold the periphery with tempered dental compound.
4. Remove all dental compound that has flowed onto the tissue side of the denture base.
5. Make a final closed-mouth impression with a suitable im- pression material.
6. Flask the RPD and process with acrylic resin.
7. Insert the RPD following the same procedure employed during delivery of the new prosthesis. Post-insertion instructions and follow-up appointments are identical to those described for a new prosthesis
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